design project - methylene chloride

CE17, 23 January 2015, PEME1000.

Design Project - Methylene Chloride

PEME1000 Technical Skills and Applications

Cai Yun Ma

CE17

Jessica Sanderson

Kishan Vedia

Muhammad Bin Jusni

Peter Smith

Samuel Karbaron

Laimutis Rimavicius

23rd January 2015


Summary

In summary, we decided to use the hydrochlorination process to form the chloromethane,

which is then converted to methylene chloride. By using this process, the yield of products

and efficiencies were maximized which not only made the process more economical but also

more environmentally friendly. By locating our plant within the heart of America’s industrial

district, sourcing of products can be done locally at a reduced cost and with low transport

emissions. By positioning the plant by the coast, any fluctuation in production from our

producers can always be supplemented by elsewhere where shipping can be used. The

methylene chloride production will not only provide the primary product which can be sold

on for use in organic solvents and paint strippers, but it will also produce valuable by-

products such as chloroform and carbon tetrachloride. Health and safety is a major influence

in the unit operations and by following the appropriate plans listed in this section of the

report, the plant will be able to operate safely.

Word Count: 167

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Table of Contents

3.4 Introduction............................................................................................................................... 4

3.5 Process route evaluation, process selection...................................................................5

3.6 Process Flow Diagram......................................................................................................... 12

3.7 Ethical Issues.......................................................................................................................... 13

3.8 Sources and Properties of Raw Material Feedstocks.................................................15

3.9 Discussion of Unit Operations and Assessment of any Issues Related to Materials of Construction.......................................................................................................... 22

3.11 Uses and Applications of Methylene Chloride...........................................................25

3.12 Safety, Health and Environmental Issues...................................................................36

3.13 Process economics............................................................................................................. 40

3.14 Conclusion............................................................................................................................. 44

3.15 Acknowledgments.............................................................................................................. 45

3.16 References............................................................................................................................. 46

3.17 Appendix................................................................................................................................ 51

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3.4 Introduction

The purpose of this report is to gain a better understanding into the process of choosing the

best synthesis route for an industrial chemical and to gain a clear overview regarding the

synthesis of methylene chloride and its mechanical and chemical properties. Moreover,

understanding principles of synthesis methylene chloride such as chlorination and

hydrochlorination is one of the aims of this project. Other than that, the selection of the

process must be based on economic terms. The other aim of this report is to increase the

safety awareness when handling and managing chemical substances.

In this report, an in depth investigation will be undertaken to determine the best, most

efficient route to produce methylene chloride. It will start by considering the process route for

the synthesis of the chemical, comparing two processes and selecting the most suitable based

on its merits. A process flow diagram is contained detailing the different stages of the chosen

process. A discussion on the ethical issues of the project is contained, debating the human

impact of the project. A section containing a list of the raw materials required for the process

is included in the report, with a section reviewing the unit operations required in the plant and

possible construction issues associated with them. The investigation also required a detailed

look into the process chemistry of the reaction, the uses of the products, the possible health

and safety concerns associated with the process and the process economics of the synthesis of

methylene chloride. Finally, a conclusion will sum up all the information gathered and give

the main findings of this report.

For the investigation, it is expected that the chemical plant will be based on the Gulf Coast.

The Gulf Coast, on the South basin of the United States of America is known as the ideal

location to synthesise methylene chloride due to its logistic and suitable geographical factor.

Apart from that, methanol and chlorine, raw materials for synthesis of methylene chloride is

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widely available at Gulf Coast. The geography of this location helps for the transportation of

this chemical. The Gulf Coast is near to the harbour so it easy to transport methylene chloride

from the plant to the other parts of the world by shipping. Hence this factor will minimise the

cost of transportation because the plant is near to harbour and source of raw materials. The

disadvantage of having a factory in Gulf Coast is due its natural catastrophe, which can

damage the factory itself and disrupt the process of producing the chemical.

Word Count: 421

3.5 Process route evaluation, process selection

The production of methylene chloride involves a two-stage process which is followed by the

washing and separation of the products. There were several options for the first step of the

reaction where chloromethane was formed in preparation for its conversion to methylene

chloride. The first option was Hoechst process which involved a free radical substitution,

reaction using chlorine and methane in the presence of ultraviolet light. Another route

consisted of the vapour-phase reaction between hydrogen chloride and methanol using a

catalyst in a process commonly used by the Dow chemical company. The liquid-phase version

of this reaction consists of the catalytic bubbling of hydrogen chloride through liquid state

methanol. All of the above routes provide the chloromethane which is required to produce

methylene chloride in a free radical substitution reaction in the same manner as the Hoechst

process.

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Step 1: Producing Chloromethane

Hydrochlorination of methanol: Dow Process

The chosen route for the production of chloromethane was the vapour-phase

hydrochlorination of methanol as shown by the process flow diagram in figure 3. In this

process an activated charcoal catalyst is used to form a dimethyl ether from two methanol

molecules as shown in equation 1. The dimethyl ether is then able to react with the

surrounding hydrogen chloride in a nucleophilic substitution reaction to produce the

chloromethane as required. This catalysis is shown below in equations 1 and 2. This occurs

within the temperature range of 673K to 773K so that the rate is sufficiently fast whilst

maintaining a good yield of chloromethane. The exothermic nature requires good control of

the temperature to ensure that the conditions are no so as to favour the endothermic side of

equation 1 and 2.

2CH3OH ↔ (CH3)2O + H2O (1)

(CH3)2O + 2HCl → 2CH3Cl + H2O (2)

Methanol, hydrochloric acid, sodium hydroxide, chlorine and a catalyst are required for the

hydrochlorination process. As for the initial stage of hydrochlorination the reaction is carried

out at around 623 K, therefore, it is performed of in a vapour phase due to methanol boiling

point being 337.9 K. There are different catalysts, which can be used to speed up the

reaction: cuprous chloride, activated charcoal and zinc chloride. `Cuprous chloride and

activated charcoal are both insoluble in water. Melting and boiling points differ between the

three catalysts. Cuprous chloride has a boiling point of 1763 K, zinc chloride is 1029 K and

activated charcoal has a boiling point of 5100 K.

Whilst only water is produced as a by-product that must be disposed of, methanol is a highly

flammable volatile liquid, known to be an irritant if touched in its liquid form and toxic if

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inhaled in its gaseous formi. More seriously, hydrogen chloride is corrosive to the skin when

in the air, and has moderately high toxicityii, making it very important to certify safe handling

and storage.

Chlorination of Methane: Hoechst Process

The first option involves reacting methane with gaseous chlorine in the presence of UV light.

The reaction is a free radical substitution whereby the UV light provides enough energy to the

chlorine-chlorine bond so that it may break to form two chlorine free radicals which initiates

the reaction as shown in figure 1. The Cl-Cl bond is the weakest of all the bond involved with

a bond enthalpy of 242 kJmol-1 and therefore breaks first in the initiation step.iii

The next step is the propagation step, during which one of the chlorine free radicals reacts

with a hydrogen atom of the methane, thus forming hydrogen chloride gas and a methyl

radical. This mechanism is shown in figure 2, which has a total enthalpy change of -15 kJmol -

1 making it exothermic. iv

Figure 1. Initiation of chlorine in the presence of UV light.

Figure 2. Propagation of the reaction.

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The propagation is followed by a termination reaction where the methyl radical then reacts

with the other chlorine free radical that was formed in the initiation reaction to form

chloromethane as illustrated in figure 3. This has a total enthalpy change of -339 kJmol-1.v

The entire reaction occurs without the need for a catalyst in a closed system. The reaction

occurs within the temperature range of 623K and 723K at 1atm, with the reactants being

prewarmed before mixing to ensure the complete reaction occurs with the reactants in their

gaseous states.vi The reaction is exothermic with an enthalpy change of -112 kJ under the

given conditions which is used to maintain the elevated temperatures used in the reaction.iv

The large change in enthalpy can make cooling a problem in the system and requires extra

funds to ensure the system is maintained at a suitable temperature. Methane is also highly

flammable gas, which poses an immediate fire/ explosion hazard if released into the airvii.

Whilst chlorine is a highly toxic, corrosive and irritating gas if inhaled by humans. Chlorine is

also an extremely oxidizing gas which will not combust itself, but cause the combustion of

other gases around itviii.The potential hazard of the reactants will require extra fund to ensure

they are safely stored and transported in the proper manner.

The raw materials required for the initial stages of direct chlorination are methane and

chlorine, both in the gaseous state due to their very low boiling points. Also, due to the high

reactivity of chlorine the reaction between it and methane is quick. Sodium hydroxide is used

as a neutralizer, because it is an alkali. It is soluble in water but not in non-polar solvents.

Figure 3. Termination.

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Sulphuric acid is used in drying column and despite to its reasonably low melting and boiling

point (282 K and 610 K respectively), it must be kept in between these temperatures to work

efficiently.

Liquid-Phase Production

A further method which can be used to produce chloromethane involves bubbling excess

hydrous hydrogen chloride through liquid methanol. The reaction occurs in the presence of a

either a zinc or aluminium chloride catalyst at a temperautre between 373K and 423K whih is

around the reflux temperature. The methyl chloride produced can then be vaporised from the

reactor and the HCl is stripped and recycled back into the reactor. This has the same enthalpy

change as the Dow process with an exothermic value of -34.7 kJmol-1.

A variation of this method requires no catalysts, however it can produce up to 4% dimethyl

ether when cheaper HCl steam is used. The cost of removing the dimethyl ether far outweighs

the cheaper HCl and hence the reaction is only ever commercially done using high quality

HCl. While liquid-phase reactions have lower capital investment, the product value is lower

and can therefore only outweigh the use of vapour-phase reaction on a small scale. ix Even

with the use of clean HCl, the risk associated with the formation of forming dimethyl ether in

the solution is too much compared to the benefits of using this route. Dimethyl ether is a very

flammable, colourless gas with an extremely low flashpoint. If released into the atmosphere it

is likely to cause ignition of the air due to its low flashpoint, and is known to cause dizziness

and irritation if inhaled by humans. The associated risk with the dimethyl ether further

influences the decision not to use liquid-phase production.

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Step 2: Producing Methylene Chloride

During this phase of the reaction, a free radical substitution reaction occurs, as described in

the Hoescht Process, between chlorine gas and the chloromethane. The reaction occurs under

the same conditions and therefore gives the same enthalpy values and also releases a

hydrogen chloride molecule for each interaction which can be recycled back into the system.

The recycling of hydrogen chloride can then be directly redirected to the reactor in the Hoerst

process which will reduce costs but provide less purity.

The exothermic nature of the reaction means its temperature must be kept at a level that

comprimises between yield and rate as stated in the explanation of this process above.

The reaction is the only commertially sustainable route for the final stage an even it has its

drawbacks. The free radical substitution occurs as a continuous chain reaction where the

chlorine free radicals are able to react with the dichloromethane to produce trichloromethane

and tetrachloromethane in a 70:27:3 ratio respectively. This means that separation is required

for the products which increases costs and increases the capital costs for equiptment.

The Hoescht process is the only feasable reaction for the production of the final product and

therefore will be the selected route regardless of step 1.

Step 3: Washing and Seperating

The final mixture formed from step 2 must then be seperated into its constiuents as required.

The solution is first washed with sodium hydrocxide which neutralises the excess

hydrogchloric acid that froms below its melting point during the cooling process. The

neutralised product is the fractionally distilled and the individual solutions are removed and

stored. This is a standardised process across all of the methods above as the mixture is the

same due to the same step 2.

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Selection.

The reason for our decision to use hydrochlorination followed by chlorination was based upon

multiple influencing factors revolving mostly around using the most economical methods

whilst remaining abiding to ethical standards. The first of which is that up to 70% HCl might

be reused in-house making the hydrochlorination of methanol the most efficient and viable

processing technique, which is only possible with the use of both processes in situ. Not much

machinery is required to install the plant, therefore lower capital investment is required (Refer

to section 3.13). In terms of the catalysts, activated charcoal was chosen due to its highest

boiling point and, most importantly, low cost which enhance the economy of the entire

process.

Word Count: 1593

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3.6 Process Flow Diagram

For the description of the flow diagram refer to the section 3.9.

3.7 Ethical Issues

In planning this plant, the ethical issues of the production and uses of the product, methylene

chloride, must be considered. These issues will affect the companies that own and fund the

plant, the consumers of the products of the plant, the local residents that live in close

proximity to the plant and the local authority which the plant is located in. The solution to

these issues will not benefit all of the relevant stakeholders, but will uphold the engineering

code of ethics set out by the Royal Academy of Engineering. The issues that can be associated

with the plant would be issues such as the process route that is being chosen, location of the

plant, the effect this plant will have on local communities, the uses of the produced materials

at the plant and the transport of the raw materials and finished product.

There are several issues to be dealt with when producing a methylene chloride plant.

Methylene chloride being toxic when inhaled at large amounts means that breathing apparatus

must be issued to all operating staff at the plant that can be exposed to the chemical. However

there is a possibility of a major leakage in the plant and the local community could inhale the

Figure 4. Process flow diagram for the hydrochlorination of methanol.

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toxic gases. Consequently this is where the ethical issue of placing the plant in close

proximity to large communities should be considered. It is impractical to issue ventilation to

the whole community to wear at all times, so other solutions must be considered. Although

locating the plant in a remote location would affect the cost of transporting raw materials, it

would significantly reduce the impact of a leakage on the local community, as the community

is much smaller. This may make the operation economically unviable for the operating

companies, so a compromise must be made between economics and ethical issues.

Methylene chloride is also said to be very corrosive when the gas comes in contact with the

skin, hence all the operating staff must be given proper protective clothing that they are

required to wear when operating machinery or in close proximity to the storage units

containing methylene chloride. This leads to the issue of storage, transport and sale of

methylene chloride as the storage tanks must be properly and regularly checked for leakages

or cracks. The transportation vehicles must also be checked for the leakages and cracks as it

could lead to leakages on the road which in turn could lead to fatal issues, with adverse effects

on the companies, as they are losing product, and therefore profits, the local community, as

they are affected by road closures due to leakages, and the local authorities, as they will need

to organize clean-up of the roads. To combat this, operating staff at the plant must be given

clear instructions on when to conduct the checks and also proper training must be given to

educate staff on how to operate the storage systems.

Word count: 488

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3.8 Sources and Properties of Raw Material Feedstocks

Table 1. Table describing potential suppliers of raw materials required to produce methylene chloride, through process of hydrochlorination.

Raw Material Sources and Supplier

Chlorine and caustic

soda

Chlorine and sodium hydroxide (caustic acid) are produced

simultaneously in membrane plants. Two of the largest

suppliers are:

1. Dow Chemical Companyx – situated primarily in the

US, founded in Michigan. Dow has around 20 plants

across the world. Dow is the second largest chemical

company in the US. Revenue is forecast to increase

over the next 5 years whilst growth will slow for the

company.

2. Georgia Gulf Corporation – 47 locations across the US

(now part of Axiall corp.). Growth is also set to

increase, providing a stable company.xi

3. Ercros S A in Spain is also a producer of chlorine and

caustic soda. Ercros is smaller than the previous two

suppliers.

4. Praxairxii also supplies chlorine and caustic soda as a

by-product. This is useful because it also supplies

methane and thus could be used for both.

The stability of economies needs to be taken into account.

Spain’s economy is more venerable than that of the US and

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therefore there is a greater risk of the industry facing problems.

Although currently improving.

World supply of chlorine and caustic soda does not seem to be

an issue.

Sulfuric Acid 1. Southern Chemical Statesxiii is a family run business

situated in Southern United States. It is the largest

supplier of sulfuric acid for industrial use in

Southern US. It is also award winning. However, it

isn’t a large company in comparison to alternative

plants.

2. Norfalcoxiv sells and distributes about 2 million

tonne of sulfuric acid per year. It has plants across

the world (mainly North America).

Sulfuric acid production is not scarce. These two companies,

however, are stable. Norfalco is an international company and

in the USA therefore there is a degree of economic stability.

Methanol 1. Atlantic methanol production company LLC.xv

Situated in West Africa it is one of the cheapest

methanol plants.

2. Methanex Corporationxvi is the world’s largest

supplier of methanol. Methanex has plants all over

the world and is steadily growing.xvii

Globally, Africa is one of the smallest producers of methanol.

The largest being China by a considerable amount. China is a

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rapidly growing economy that is arguably trustworthier.

Hydrochloric acid 1. Hydrochloric acid is also available from Dow

Chemical Company and the Georgia Gulf

Corporation (See above for details)

2. Tosoh Corporationxviii. Located in Tokyo Japan.

However Tosoh has manufacturing facilities all

over the world including Europe and the UK. This

means that hydrochloric acid would be more easily

accessible. The company is steadily growing.

Japan is very economically stable, having one of the largest

growing economies in the world.

It can be seen in the flow diagram the HCl is recycled back

into the process. Initially HCl will be needed, however a

smaller quantity will be needed in comparison to methanol.

Possible

Catalysts

Cuprous

Chloride

Cuprous Chloride and Zinc Chloride are available from many

minor chemical companies in powder form. Although these

businesses may be unstable they are still accessible. India I s a

major manufacturer of these chemicals.xix

Zinc

Chloride

Activated

Charcoal

Activated charcoal is widely available from varies companies.

Cabotxx had locations worldwide, located primarily in America.

From this research it can be seen that the raw materials required are all easily accessible.

Most materials are more highly available from the USA; Dow Chemical Company is the

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largest producer of the chemicals required. This needs to be considered when deciding upon

location of the plant. It seems that no materials would cause a problem.

Properties and considerations of the raw materialsxxi

Chlorine xxii

Chlorine is a green gas, with a strong smell, at room temperature. Chlorine is highly toxic.

Skin contact causes severe irritation with burns and inhalation may cause irritation of

respiratory tract or damage to lungs. Chlorine is also highly reactive. In chlorination reaction

a chlorine molecule is broken down into radicals, which are highly reactive particles (as seen

in section 3.10). It is not flammable in air. However, it makes explosive mixtures with

hydrogen.

Boiling point: 239 K

Melting point: 172 K Chlorine will thus be in the gaseous state during the reaction where the

temperature is 573 – 673 K.

Caustic soda i

Sodium hydroxide is odorless and colourless liquid alkali. In Hyrdochlorination it is used in a

scrubbing process. Sodium hydroxide is highly soluble in water and insoluble in non-polar

solvents.

Melting point: 591.2 K

Boiling point: 1661.2 K

Sodium hydroxide will be in liquid state during both processes. Sodium hydroxide is

corrosive and toxic and is an irritant upon contact with skin, ingestion may cause severe

burning of lips and throat. Overexposure can cause burns and scarring.

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Methanol xxiii

Methanol is a colourless liquid at room temperature. Methanol is also miscible in water.



For Hydrochlorination reaction temperature s maintained at about 623 K, therefore again

methanol will be in the gaseous state. Methanol is volatile and flammable; therefore vapour

may form explosive mixtures with air.

Upon contact, may cause slight irritation of the skin and eyes. Upon inhalation and ingestion

methanol is toxic, may cause blindness.

Hydrochloric Acid xxiv

Hydrochloric acid is a colourless liquid. It is an acid and dissociates in water. Physical

properties depend entirely on the concentration and molarity of the solution. During the both

processes hydrochloric acid is in the gaseous state. During Hydrochlorination, HCl is

recycled. Upon contact, hydrochloric acid is very hazardous and causes irritation (extent

dependent on molarity of acid).

Sulfuric Acid xxv

Commonly used as a drying agent in hydrochlorination process, this is because it has a high

affinity for water and therefore can be used to remove water from other compounds. Sulfuric

acid is a yellow, viscous liquid and is soluble in water.



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Upon contact with skin sulfuric acid is corrosive and an irritant. It will produce burns.

It is hazardous upon ingestion and inhalation. Inhalation may produce irritation of respiratory

tract; over exposure may results in death.

Cuprous Chloride xxvi

Cuprous Chloride is a white crystalline solid, which is insoluble in water.



Cuprous Chloride is very hazardous upon ingestion and inhalation. It’s corrosive to skin and

eyes.

Activated Charcoal xxvii

Activated charcoal is carbon with increased surface area, thus more effective adsorption. The

increased surface area makes for a more effective catalyst, increasing rate of reaction further.

It is insoluble is water. The substance is also odorless.


Melting Point: 3823.2 K

The temperature for the process is around 573 K and therefore this will be a solid.

It is only slightly hazardous upon contact with skin, or upon inhalation, or ingestion.

Zinc Chloride xxviii

Zinc Chloride as a white powder and is highly soluble in water.



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Upon skin contact and inhalation zinc chloride is very hazardous. Eye contact may also cause

blindness.

Upon the choice of the catalyst, the cost needs to be taken into consideration, refer to section

3.13, process economics.

Word Count: 1191

3.9 Discussion of Unit Operations and Assessment of any Issues Related to

Materials of Construction

Methylene chloride is a volatile colourless liquid; it is a very sweet smelling chemical similar

to that of etherxxix. There are various process routes that can be used in producing methylene

chloride on an industrial scale and that includes the chlorination of methane or the

hydrochlorination of methanol, both processes include the production of methyl chloride

which is then further chlorinated to produce dimethyl chloride which is also called as

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methylene chloride. In countries such as the United States, most companies have adopted to

using the hydrochlorination of methanol as a viable process route. It is a continuous

production process and not a batch process whether it is the direct chlorination of methane or

the hydro chlorination of methanol is chosenxxx.

In the building of this plant, the process where the hydro chlorination of methanol with

hydrogen chloride and chlorine is chosen. There are several unit operations that need to be

considered here, such as reactors where several reactions occur, quench towers, stripping

towers, and storage units. The process begins in the hydrogen chloride reactor with the vapour

phase reaction of hydrogen chloride with methanol in the presence of a catalyst; the catalyst

used in these processes includes a fixed catalyst bed of activated charcoalxxxi. The tower is

maintained at 623K as the reaction occurs in the tower methyl chloride gas is formed. This

gas then passes through several unit operations such as the quench tower, the scrubber and the

drying towerxxxii. The quench tower is a unit operation that is highly responsible for cooling

down the exhaust gases from the high temperatures they were being expelled at to saturation

temperaturesxxxiii. The exhausts gases are usually cooled using water vapour, and are used are

pre coolers usually for scrubbers in the scrubbing tower. Scrubbing towers are towers that use

liquids to remove impurities from exhaust gases before entering the drying towerxxxiv. In this

particular process caustic soda is used to remove the impurities from methyl chloride gas.

There are several types of scrubbers such as spray tower scrubbers, packed bed scrubbers,

moving bed scrubbers and mechanically aided scrubbers. These different types of scrubbers

use different materials specifically to remove impurities, each type of scrubber is used for

different gases with different types of particulate impurities such as the spray tower scrubbers

which are used for large particle impurities and whereas the packed bed scrubbers are used for

smaller impuritiesxxxv. As the gas is quenched and scrubbed from impurities it then passes

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through the drying tower which is responsible for removing most of the moisture from the gas

so that the “wet” gas is converted into dry gas and can then later be chlorinated to produce

methylene chloride. H2SO4 is usually used in drying towers with the acid strength begin as

low as 78 percent and as high as 98.5 percent. Different types of plant handle different

concentration of acids such as the acid plant handling up to 78 percent, the acid regeneration

plant handling at 93 percent and the sulphur burning acid plant using acid concentrations of

up to 98.5 percent. Temperature at the drying tower are moderately low compared to other

unit operations and lie around 343 K, but as concentration of acid is increased the

temperatures used are usually higher but are limited to the materials that maybe used in the

construction of the tower, piping and acid cooler. The operating pressure also differs from the

type of tower being used. Where acid regeneration plants work in vacuum conditions, sulphur

burning acid plants actually works in a slight negative pressure or a high positive pressure and

that depends on where the blower is placed in the drying towerxxxvi. As the methyl chloride

passes through these several types of unit operation it then goes through the thermal

chlorinator where it is then reacted with chlorine with the help of heat to produce the finished

product of methyl chloride. The methylene chloride then proceeds to enter the HCL stripper.

The HCL stripping unit is usually accountable for the removal of the dissolved HCL from the

gas, which is then sent back to the start of the process hence the HCL is recycled in the

process. As the ethylene chloride is stripped off from HCL it then precedes towards the

methylene chloride tower, which is responsible for the storage and treatment of the liquid in

the final stages before it can be transported to several customers in need of the product. In this

unit, the methylene chloride is then distilled to produce pure methylene chloride and

chloroform. Chloroform is a by-product produced in either of the process and is stored and

later sold to other markets in need of the product. In the chloroform tower, the chloroform is

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distilled to produce pure chloroform and heavy carbon tetrachloride products, which can also

be sold to suitable marketsxxxvii.

Another matter that must be discussed is the choice of materials in building the plant, which is

affected by the process being chosen. Since the hydro chlorination of methanol involves the

usage of raw materials such as hydrogen chloride, methanol and chlorine, special care must be

taken to prevent tanks that store and react these chemicals are corrosion resistant to these

chemicals, also extra care must be taken that if the methyl chloride gas or the methylene

chloride is to leak the materials that is used to build the plant are resistant to the effects of

methylene chloride. Tanks are normally used as reactors and storage units, which are usually

made of stainless steel due to its high tensile and compressive strength along with its excellent

corrosive properties with highly, concentrated acids, alkali and water.

Word Count: 964

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3.10 Process Chemistry, Process Operating Conditions and Associated

Challenges

Methylene chloride is formed from the free radical substitution reaction that occurs between

chlorine gas and chloromethane under ultra violet conditions. Firstly, however, the

chloromethane is produced from one of two potential reactions.

Step 1: Hydrochlorination of Methanol

The chosen route to the production of chloromethane involves reacting hydrogen chloride gas

and methanol in the presence of a catalyst.

The reactants are first mixed between a temperature of 453K and 473K to ensure they are in

their gaseous states as this is well above the boiling points of both reactants. By reacting the

substances as gases, better mixing can occur to ensure that there is the maximum yield. The

reactants release heat as the reaction unfolds which allows the temperature to rise within the

range of 673K to 773K.xxxviii

The overall reaction is shown in equation X, however in actuality the presence of the catalyst

causes the reaction to be accompanied by a two-step process. Firstly the chloromethane forms

a dimethyl ether, (CH3)2O, in a reversible reaction as described in equation 1, before reacting

with HCl as shown in equation 2. The reactions 1 and 2 are highly exothermic, whilst reaction

1 is ruled by equilibrium. Using Le Chatelier’s Principle it can be predicted that by removing

the dimethyl ether and the water from the reactor, the methanol will produce more product,

hence the use of a continuous process.xxxix The reaction schemes are shown overleaf for the

catalytic reactions in figures 5 and 6.

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I. 2CH3OH ↔ (CH3)2O + H2O (1)

II. (CH3)2O + 2HCl → 2CH3Cl + H2O (2)

The overall reaction has an enthalpy change of -34.7 kJmol-1. Due to the reversible step in

equation 1, the temperature must be maintained to provide the optimal yield whilst not

compromising the rate of reaction. Figure 7 demonstrations how temperature effects the

equilibrium conversion and shows how a temperature of ~500K provides a good yield and

will also allow for a quick rate of reaction. This can be explained by Le Chatelier’s Principle

because the exothermic nature of the reaction means that decreased temperatures favour the

forward reaction to produce the dimethyl ether.

Figure 5: Catalytic Reaction I

Figure 6: Catalytic Reaction II

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xl

There are several catalysts that could be used in the reaction, many of which have similar

properties as described section 3.8. The favoured catalyst in industry is often activated

charcoal due to its high commercial availability, xliii however other options include fixed bed

reactors with zinc or cuprous chloride.xli The amount of catalyst that is available must be

controlled to ensure that the reaction does not become uncontrollable due to its exothermic

process. To help control such a reaction cooling tubes and jackets can be used to reduce the

internal heat and maintain a controlled reaction.xlii

Step 2: Producing Methylene Chloride

Methylene Chloride Production

The methyl chloride produced the process as described above must then be reacted to from the

methylene chloride as required. The pure methyl chloride is reacted in in a free radical

substitution reaction whereby ultraviolet light catalyses a reaction between chlorine and

chloromethane. HCl is produced which is then recycled back into the first step where it forms

more chloromethane. The recycling process reduces the overall costs for production as

described in section 3.13.

Figure 7: The Effect of Temperature on Equilibrium Conversion

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The reaction is carried out with only ultraviolet light being used as a catalyst under

atmospheric pressure. The reaction produces large amounts of heat due to its very exothermic

reaction which has a total enthalpy change of -112 kJmol-1. Before the reaction produces

sufficient heat to maintain the reactor temperature within the range of 623K to 723K, the

reactants are warmed. The pre-warming heats the reactants to a temperature of ~470K which

is well above the boiling points of the chlorine and chloromethane, whose boiling points are

239Kxliii and 249K respectively.xliv By mixing the reactants in their gaseous states, the collision

frequency is very high without the need for any costly stirring equipment.

The chlorine radical generated in the initiation reaction substitutes for one of the remaining

hydrogens on the methyl chloride to form methylene chloride as shown in figure 8.

Initiation occurs spontaneously as soon as the chlorine is exposed to UV, as shown in figure

9. The Cl-Cl bond is the weakest of all the bond involved with a bond enthalpy of 242kJmol-1

and therefore breaks most readily first in the initiation step.xlv

Propagation follows initiation, where the chlorine free radical spontaneously reacts with the

chloromethane in a mechanism as shown in figure 10. The total enthalpy change of this step is

-15 kJmol-1 making it exothermic and hence providing heat to the environment. xlvi

Figure 8: The Effect of Temperature on Equilibrium Conversion

Figure 9: Initiation of chlorine in the presence of UV

29


Termination occurs after the methyl radical is formed and as illustrated in figure 11, forms the

dichloride as required. This has a total enthalpy change of -339 kJmol-1, making it a highly

exothermic step of the reaction.xlvii

However, the reaction occurs as a chain reaction with the potential to form trichloromethane

and tetrachloromethane as well as the dichloromethane as shown in figures 12 and 13. The

product therefore only gives a 70% yield of methylene chloride, with 27% of the final mixture

being trichloromethane and 3% being tetrachloromethane.xli To maximise the yield of

methylene chloride the reaction must occur with the chlorine content being monitored and

minimised enough to minimise excess reacting with the methylene chloride. The product of

the reaction must then be fractionally distilled to separate the components and remove the

methylene chloride.

Figure 10: Propagation reaction

Figure 11: Termination

Figure 12: Trichloromethane Figure 13: Tetrachloromethane

30


Step 3: Washing and Separating

The final mixture formed from step 2 must then be seperated into its constiuents as required.

The solution is first washed with sodium hydrocxide which neutralises the excess hydrogen

chloride which condenses to form hydrochloric acid during the cooling process. The

neutralised product can then be fractionally distilled and the individual solutions are removed

and stored.

During fractional distillation the dimethylene chloride condenses at a temperature of 313Kxlviii,

compared to 333Kxlix for trichloromethane and 349.5Kl for tetrachloromethane. The large

difference in boiling points makes this process simple and allows for very high purity

products that can then be sold on as a profitable by-product as described in section 3.13 of this

report.

Word count: 1011

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3.11 Uses and Applications of Methylene Chloride

Methylene chloride is known as dichloromethane (IUPAC ID) with the formula

CH2Cl2.Nowadays, there are a lot of uses of methylene chloride in industrial, pharmaceutical

and household products depending on the physical and chemical properties of methylene

chloride. The unique properties of methylene chloride have led to its wide variety of

applications such as high solvency power, relative inertness, non-flammability, low toxicity

and low boiling point. The main use of methylene chloride is as a paint and varnish removal.

Moreover, methylene chloride act as an extraction medium, metal cleaning and propellant in

aerosols (1).

One of the uses of methylene chloride in industry is metal cleaning. Metal cleaning is needed

before painting, planting, plastic coating and many more. Metal cleaning is the process where

the oils, waxes, greases and soils on the surface of metal is removed by using the vapour

degreasing methodli. The solvent is boiled by the heating coil and the solvent evaporates. The

solvent vapour will dissolves degreases part of the metal. The low boiling point of methylene

chloride is suitable for this process because it requires less energy to boil the solvent and the

process becomes more economical and lower in costs.

32


Figure 14. Open-top Vapour Degreaserslii

Further research has shown that methylene chloride can be used as propellant for aerosol.

European Chlorinated Solvent Association, ECSA (1) from its review states that around 4%

of European usage of aerosols contains methylene chloride (ECSA,2007). The methylene

chloride would reduce the pressure inside the aerosols and thus reduce the risks of explosion

of aerosols. Other than that, the methylene chloride has low flammability of properties and

lead to a great advantage of using methylene chloride as a propellant because it reduces the

flammability of the aerosols. These properties of methylene chloride makes the aerosol is

safer to use. One of the advantages of methylene chloride is it has potential to replace the

ozone-depleting substances such as chlorofluorocarbon (CFC). Methylene chloride also acts

as a solvent for active substances such as hairspray resin and deodorant instead of propellant

gas that is needed to stabilise the pressure inside the aerosol.

For many years, methylene chloride dominates as the active ingredients for paint

removers. This is because the methylene chloride will act as a solvent and able to dissolve the

paint and also soften it. The solvent will soak the paint and swell it. Thus it is easy to remove

the paint layer. The paint then is removed mechanically or hand-removed. However,

33


Methylene chloride is extremely volatile compound so usually methylene chloride will mix

with thick waxy materials to lower its boiling point and slows the rate of evaporation. Other

than that, methylene chloride is hazardous and corrosive to skin but generally the paint

removers containing methylene chlorides remains popular because the product works in 30

minutes or less but safer products will take a longer time to soften the paint so this paint

remover remains popular although it is hazardous.

The marketing of methylene chloride for paint remover has been banned by European

Union because of its toxicity. Vapour of methylene chloride can be dangerous to nervous

systemliii. Further research has been done to find alternative way to replace the methylene

chloride-based paint removers with other chemical compound that is less harmful to human

such as dibasic ester and dimethyl succinate. Dr. Bruno Orthern presented his research during

Paint Stripping Agents in Brussels shows that methylene chloride shows a high relative risk

level which is in range between 4650-46500 when compared to other chemical substances

such as dibasic ester which is 40-400liv. The marketing for methylene chloride-based paint

removers is decreasing year by year because of its toxicity and more new compound has been

discovered to replace methylene chloride as paint removers.

Methylene chloride is used as a solvent for production and coating process in pharmaceutical

industry. Extraction of raw materials and then the products of extraction are further processed

for pharmaceutical purposes. Methylene chloride in extraction product can be removed easily

due to its low boiling point properties so the less heat required to vaporise the methylene

chloride out of the product without having thermal degradation of the product. In order to coat

the pills and tablets, methylene chloride must be blend with other solvent such as methanol or

ethanol.

34


In food industry, methylene chloride will act as a caffeine remover and extract solvent to a

heat-sensitive substances such as cocoa, edible fats and spices. In decaffeination process,

methylene chloride act as a decaffeination agent to speed up the reaction and minimize the

‘’washed-out’’ effect made by water. Caffeine is a water-soluble content and water is used in

all process but water itself is not enough so decaffeination agent must be usedlv.

In chemical industry, as usual methylene chloride will play its role as solvent in production

of polycarbonate plastic. The physical properties of methylene chloride, low boiling point

bring advantages of methylene chloride in chemical industry so it will easily remove from the

product and polycarbonate is easy to dissolve in methylene chloride rather than water.

Another usage of methylene chloride is production of triacetate flake and this flake will

undergo further processes to produce textile fibres and photographic film.

Methylene chloride is used as a chemical intermediate. Other than that, methylene chloride

also has been used in food and pharmaceutical process. It is used as extraction medium

because of its high solvency, high purity and easy to distilled off from the final product.

Adhesive formulations, plastic processing and secondary blowing agent in polyurethane foam

is the examples of usage of methylene chloride. There is a lot of application has been used

from methylene chloride such as photo-resistant stripper in the production of printed circuit

boards and as a refrigerant.

Based on Eurochlor’s statisticlvi, the sales of methylene chloride decreasing year by year. The

sales drop from 113 00 tonnes in 2010 to 104 000 tonnes in 2011. This is because the

European Union has banned the usage of methylene chloride in paint stripper and restrict on

the marketing bring the significant drop in methylene chloride’s marketing.

35


Figure 15. Graph of European Market for Chlorinated Solventlvii

Table 2. Table of European Market for Chlorinated Solvent.

Word Count: 1163

36


3.12 Safety, Health and Environmental Issues

In this section, the environmental consequences of the process will be considered,

including generating the raw materials and disposing of any waste the process leaves.

The inherent hazards of the process used to produce methylene chloride will also be

considered in this section.

One of the main reactants of this process is methanol, which has environmental impact

on generation. It can be produced from natural gas or biomass, or indeed any material

that can form a synthesis gas, is produced under moderate temperatures and produces

between 0.54-1.0 tonnes of carbon dioxide per tonne of methanol produced lviii. The

other main reactant of the process, chlorine, is produced from the electrolysis of sodium

chloride. Electrolysis is known to be a very energy intensive production method,

meaning depending on how the electricity used is produced, it can be a highly polluting

process. However, when producing chlorine, caustic soda is produced which is also used

in the processlix. In the location chosen, on the Gulf Coast, transporting emissions will be

kept to a minimum due to the proximity of the producers of the raw materials.

During the process, the major sources of day to day emissions are from equipment leaks,

storage tanks and transfer of the products from storagelx. These day to day emissions

release small amounts of methylene chloride and the reactants into the air. Methylene

chloride is classified as a Hazardous Air Pollutant by the EPA, and is recommended to be

safe only when kept below 3mg/ cm3 in the atmospherelxi. Chronic inhalation of

methylene chloride above the recommended reference concentration can lead to

dizziness, memory loss and nausea, so therefore it is important to control day to day

leaks as much as is possible. Apart from the adverse effect on human health, release of

methylene chloride into the atmosphere has no other hazards. It is not classified as a

37


volatile organic compound, even though it contains a high proportion of chlorine atoms,

due to the chemical being very unstable in air and breaking up before it reaches the

ozone layerlxii.

If the process were to catastrophically fail, hazards from the release of methylene

chloride would be much more severe. In large amounts, methylene chloride is known to

break down into carbon monoxide in the body, leading to carbon monoxide poisoning.

Direct contact with higher concentrations of methylene chloride irritates the skin and

eyes. If a failure on this proportion was to occur, the reactants would be released also,

including chlorine and methanol. At levels above 3ppm, chlorine is an irritant, and can

be toxic by inhalation. If large amounts of methanol are released into the atmosphere, it

can be toxic over a small range, however decomposes very quickly in airlxiii. As can be

seen, it is of vital importance to prevent catastrophic failure of the plant.

In the process hydrochloric acid, chloroform and some carbon tetrachloride are

produced. Hydrochloric acid is recycled to an earlier stage in the process, as can be seen

on the process flow diagram, however the two other bi-products must be deal with by

outsourcing. Both products have uses, meaning they can be sold to other industries and

are not required to be disposed of as wastelxiv.

In the production of methylene chloride, two chlorination process takes place in a

continuous Fixed/ Fluidized Bed Reactor, one involving the conversion of methanol to

methyl chloride and the other methyl chloride to methylene chloride. Since both the

chlorination reactions are exothermic, monitoring the temperature can help indicate

when the reactions begins to undergo thermal runaway. This causes overheating of the

materials of the reactor, which can lead to material failure by thermal stresses such as

creep rupture or fatigue failure. This would lead to the release of the chemicals in the

reactors, which could include a mixture of most notably chlorine, methyl chloride,

38


methylene chloride and hydrochloric acid or a mixture of most notably methanol,

hydrochloric acid and methyl chloride. The progression of the chlorination reaction can

cause the pressure inside of the reactor to increase rapidly, which may also cause the

failure of the material used in the reactor, releasing the contentslxv.

The chemicals released from both reactors are toxic and carcinogenic, meaning it is

important to prevent reactor failure. If failure were to occur, hazards would be

minimized by isolating the reactor and providing local exhaust ventilation, however this

can be challenging to make operationally feasiblelxvi. A quenching process must occur in

the local exhaust system to stop the reaction continuing, and a suitable solvent would

have to be mixed with the relief stream to remove all hazardous chemicals from being

released into the atmospherelxvii.

To prevent the thermal runaway of the reaction, a fixed temperature alarm should be

fitted in the reactors. This equipment would alert the operators when either of the

reactions weres above the safety temperature threshold, and temperature control

processes can be implemented, such as reflux cooling or the addition of a reactant to

shift the position of reaction equilibriumlxviii.

After the chlorination process, where methylene chloride and other compounds such as

hydrochloric acid and chloroform are produced, the products are transported to a

quenching system, where the temperature of the gases are reduced, as shown by the

process flow diagram. After the gases of the mixture are condensed to a liquid, they are

transported to a distillation tower, where the product, methylene chloride, is separated.

Similarly to the reactor, the largest safety hazard posed by the distillation tower comes

in failure, where the contents of the reactor are spilled, via a small leak or complete

collapse. This would usually occur due to corrosion, overheating of tower, design faults

or structural failures. If this were to happen, emergency responses to the spill would be

39


required. These would include isolation of the spillage, secondary containment of the

remaining product in the distillation tower and the products from the chlorination

reactor, and treatment of the spillage to render it safe, in this case neutralization with a

chlorine bleaching liquor would be required. To prevent spillage from the distillation

tower, many safety measures can be implemented. These include applying surface

treatments to the distillation column to prevent corrosion, regular inspection of the

tower to check for leaks, fitting of alarms to monitor temperature/leakage and

protection for the tower from natural hazards, including high winds, flooding and

lighteninglxix.

Operators of the methylene chloride plant would be required to wear PPE, including

breathing apparatus, chemical resistant clothing and eye protection to lower the risk of

hazard to the workforce. Operators would also have to undergo stringent, in depth

training on how to work the plant in a safe manner.

Word Count: 1117

40


3.13 Process economics

The foregoing section considers the influence of process selection as well as engineering

design on the economics of an operating plant. The manufacture of methylene chloride may

take two pathways - methanol hydrochlorination or thermal chlorination of methane. The

selection of the process varies greatly depending on the prices of raw materials, which are

methanol, chlorine and methane. The output of methylene chloride is 70% in both processes

along with chloroform and tetrachloromethane, which are synthesised in the following

reactions accounting for 27% and 3% of the whole output respectively. However,

hydrochlorination of methanol has numerous advantages in terms of the sustainability and

profits raised as opposed to the process where methane is chlorinated:

Using the former process up to 70% of HCl might be reused in-house after quench

water is being stripped in dissolved methanol and chloromethane. Therefore,

considerable amount of money could be saved on raw materials.

Hydrochlorination of methanol requires fewer apparatus on the process flowsheet as

opposed to chlorination of methane hence a plant could be designed with a smaller

initial capital investment.

Choosing a location in Texas, USA has its own merits due to the largest manufacturer of

methanol being in the vicinity of this area. Besides that, 6 out of 40 companies that produce

chlorine in the USA are based in Texas as well, thus, operating costs of transportation are

lower than in any other chosen location.

Even though not much machinery is used in this type of chemical plant and capital costs for

construction and for decommissioning are reasonably low, more money could be saved by

employing idle equipment or by purchasing second-hand equipment also. However, adequate

41


storage of highly toxic products and waste incur additional expenses on the maintenance and

establishment of the plant.lxx Besides that, as exposure to methylene chloride, chloroform,

carbon tetrachloride, sulphuric acid and methyl chloride may have detrimental effects on

human health, safety equipment must be used by all of the employees in the plant

consequently generating more expenses. A huge role in determining the capital costs is played

by a business and regulatory context, which includes environmental regulation, subsidies and

other incentives and the broader context how government and business interact. To add,

import and export tariff regulations, depreciation rates, income tax rules have a huge impact

on most businesses.

In the table below, trending prices in the industrial market are shown.

Table 3. Prices of the raw materials used and products retrieved.

Item Cost (pounds)/tonne

Methylene chloride (CH2Cl2) 435 (ICIS pricing, 2014)

Chlorine (Cl2) 42 (ICIS pricing, 2014)

Hydrochloric acid (HCl) 53 (ICIS pricing, 2014)

Methanol (CH3OH) 200 (SunSirs, Commodity group, 2015)

Chloroform (CHCl3) 313 (SunSirs, commodity group, 2015)

Tetrachloromethane (CCl4) 792 (Alibaba, global trade website, 2015)

Approximately 70000 tonnes of dichloromethane could be manufactured from one plant on an

annual basis along with 27000 tonnes of chloroform and up to 3000 tonnes of carbon

tetrachloride. According to the prices in table 1, the estimated annual revenue generated from

aforementioned products is roughly about 41 million pounds. The annual expenses on the raw

42


materials constitute to approximately 28 million pounds, which accounts for 68% of the total

revenue, whereas the other 32% is a total generated profit (13 million pounds). However,

capital and maintenance costs as well as labour expenses must be subtracted from the total

profit, therefore, the actual profit fluctuates between 5-10 million pounds a year depending

also on the market prices of materials.lxxi

-2 -1 0 1 2 3 4 5 6 7 8

-30

-20

-10

0

10

20

30

40

50

60

70 Project cash flow chart

Lowest profitMedium profitHigh profit

Years

Pro

ject

cas

h fl

ow in

mil

lion

GB

P (

£)

Figure 16. Project cash flow at different profits over 10 years.

Predominantly, this graph depicts changes in the plant’s budget over a decade. Allegedly, for

the two years prior to the plant start-up up 20 million pounds of capital investment is needed

for construction and installation of the process plant. Year 0 indicates the date when the plant

was put into operation and the first profits were generated. lxxiiFrom year 0 onwards the

cumulative cash flow increases with time. Depending on the profit rate particular year is

determined, when the cash flow becomes positive indicating that the land cost, fixed capital

investment and working capital are completely repaid. To remind only, it is just a reflection of

cash flow throughout 10 years, therefore, it might differ when the plant is in process as prices

may vary widely in the market from one period to another. Nevertheless, corresponding to the

43


actual market prices at this period of the time, the process of manufacturing methylene

chloride appears to be profitable.

Overall, the efficient plant should operate under a strict schedule that gives the maximum

production rate according to the market demand, safety and maintainability.

Word Count: 832

44


3.14 Conclusion

The conclusion for this report is the understanding of overall principle of developing and

integrating unit operation. Our research has shown that the synthesis process of

dichloromethane, chlorination and hydrochlorination are similar but the hydrochlorination

process is has more economic advantages than the chlorination process. The selected process

is more economic because the chemical substances used can be recovered and less harmful to

the environment. Methylene chloride has a huge contribution to domestic products and also it

is widely used in metal and pharmaceutical industries. Most uses of methylene chloride are

based on ability to act as a solvent. The health and safety requirements stated in section 3.12

would have to be met for this operation to become practicable, such as giving PPE to

operators. According to research undertaken in section 3.13, the plant would take 2-4 years to

become profitable, so significant capital investment will be required for this plant to start.

Research undertaken in section 3.9 pointed towards using the hydrochlorination of methanol

as our process as it required fewer unit operations, meaning less capital investment would be

required at the start of the project. Research in section 3.8 pointed to locating our plant in the

Gulf Coast of the USA, as both of the processes main raw materials, methanol and chlorine,

are produced in this area, reducing transport costs.

220 Words

45


3.15 Acknowledgments

Every member of the group contributed to each group section equally, with certain people

taking lead on each section. No problems were encountered throughout the process.

Samuel – Section 3.10 on process chemistry, Sam also lead section 3.5 on process route

evaluation.

Kishan – Section 3.9 on discussion of Unit operations, lead the writing of the group ethics

section.

Peter – Section 3.12 Health and Safety, Peter took minutes of each meeting and lead the

writing of the introduction,

Laimutis – Section 3.13 on Process economics, Laimutis also lead drawing the process flow

diagram.

Muhammad - Section 3.11 on uses and applications, Muhammad also lead the writing of the

conclusion.

Jessica – Section 3.8 on raw materials, Jessica also formatted all the report (e.g. individual

sections, title pages, references, contents etc).

Jessica, Kishan, Sam and Peter took lead in writing the presentation.

46


3.16 References

47


3.17 Appendix

Group Project Assignment

Minutes of Group Meeting

Names of Students:

Name of Advisor(s):

Title of Project:

Date of Last Meeting: Date of Current Meeting:

Progress:

Peter Smith Jessica Sanderson Kishan VediaLaimutis RimaviciusSamuel Karbaron Muhammad Hafizu Jusni

Cai Yun Ma

Methylene Chloride

11/12/2014 15/01/2015

Feedback from all members of the group on research undertaken during the Winter

break.

Decision to use the hydro chlorination of methanol process instead of the

chlorination of methanol.

Deadline of Monday set for individual parts of the project to be completed.

Discussion on how the group will be organized when writing the group sections

o Decision made that the group will split into two groups of three, with one

group (Peter, Kishan and Muhammad) writing the Ethics section and the other

group (Jessica, Laimutis and Samuel) to produce the Process Flow Diagram

Decision to hold next meeting on Friday 16th January


Aims for next meeting:

Name of Minute Secretary Signature Date

Peter Smith 15/01/15

Signature of Advisor

o To begin collating information for the Process Route Evaluation section, and possibly start writing this section

o To feedback on the ethics lecture and complete the Ethics sectiono To discuss the location of the plant

49




Names of Students:

Name of Advisor(s):

Title of Project:


Progress:





Peter Smith Jessica Sanderson Kishan VediaLaimutis Rimavicius Samuel KarbaronSamuel Karbaron Muhammad Hafizu Jusni

Cai Yun Ma

Methylene Chloride

15/01/2015 16/01/2015

Collated information for the Process Route Evaluation section, and started writing this section.

Subgroup (Peter, Muhammad, Kishan) feedback on ethics lecture. Subgroup (Peter, Muhammad, Kishan) co-wrote the ethics section. Researched and decided the location of the plant would be on the Gulf Coast.

Discuss presentation style. Write the Process Route Evaluation Section. Proof read other individual sections. Subgroup (Jessica, Laimutis and Samuel) attend AutoCAD session and create process

flow diagram.

50




Names of Students:

Name of Advisor(s):

Title of Project:


Progress:





Cai Yun Ma

Methylene Chloride

16/01/15 19/01/15

Wrote large proportion of process evaluation section

Proof read all individual sections

Subgroup (Jessica, Laitmus and Sam) feedback on AutoCAD session

Began creating Process Flow Diagram

Complete process evaluation section

Complete Process flow Diagram

Decide presentation style

Begin creating PowerPoint for presentation

51




Names of Students:

Name of Advisor(s):

Title of Project:


Progress:





Cai Yun Ma

Methylene Chloride

19/01/15 20/01/15

Started to prepare for our presentation

Met with supervisor it discuss progress

Finaliazed process flow diagram

Finalized process route evaluation sections, began collaborating all written section

Finish presentation Finish process route evaluation Begin to put final document

52




Names of Students:

Name of Advisor(s):

Title of Project:


Progress:






Cai Yun Ma

Methylene Chloride

19/01/15 20/01/15

Completed process evaluation section Completed process flow diagram Decided 3 people (Jess, Kishan and Peter) would do the presentation Created summaries for each individual section for presentation

Complete PowerPoint slides Rehearse presentation

53




Names of Students:

Name of Advisor(s):

Title of Project:


Progress:






Cai Yun Ma

Methylene Chloride

20/01/15 21/01/15

Completed PowerPoint slides Rehearsed presentation Completed Presentation Collated all Individual Sections

Proof read all report Submit Report Print the report

54

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