Co

MD

a

ARR2A

KGENmE

1

w2taHtbr(n

(

0h

Industrial Crops and Products 53 (2014) 78– 84

Contents lists available at ScienceDirect

Industrial Crops and Products

journa l h om epa ge: www.elsev ier .com/ locate / indcrop

omparative evaluation of performance and emission characteristicsf Moringa oleifera and Palm oil based biodiesel in a diesel engine

. Mofijur ∗, H.H. Masjuki, M.A. Kalam, A.E. Atabani, I.M. Rizwanul Fattah, H.M. Mobarakepartment of Mechanical Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia

r t i c l e i n f o

rticle history:eceived 30 August 2013eceived in revised form6 November 2013ccepted 3 December 2013

eywords:lobal energy consumptiondible oil feedstockon-edible oil feedstocks, Moringa oleiferaethyl ester

ngine performance and emissions

a b s t r a c t

Biodiesels, which are made from various crops, as well as animal fat, are renewable, bio-degradable, andnon-toxic and are eco-friendly compared with fossil fuels. Currently, there are more than 350 oil-bearingcrops identified as potential sources for biodiesel production. In this study, the potential of biodieselobtained from a non-edible oil source (Moringa oleifera) was explored and compared with that of palmbiodiesel and diesel fuel. The physico-chemical properties of M. oleifera methyl ester were determined,and the properties of 5% and 10% (by volume) blends thereof (MB5 and MB10, respectively) were com-pared with those of palm-oil blends (PB5 and PB10) and diesel fuel (B0). The performance of these fuelswas assessed in a multi-cylinder diesel engine at various engine speeds and under the full-load conditionwhereas emissions were assessed under the both full-load and half load condition. The properties ofpalm and M. oleifera biodiesels and their blends meet the ASTM D6751 and EN 14214 standards. Engineperformance test results indicated that the PB5 and the MB5 fuels produced slightly lower brake pow-ers and higher brake specific fuel consumption values compared to diesel fuel over the entire range ofspeeds examined. Engine emission results indicated that the PB5, MB5, PB10 and MB10 fuels reduced theaverage emissions of carbon monoxide by 13.17%, 5.37%, 17.36%, and 10.60%, respectively, and reducedthose of hydrocarbons by 14.47%, 3.94%, 18.42%, and 9.21%, respectively. However, the PB5, MB5, PB10,and MB10 fuels slightly increased nitric oxide emissions by 1.96%, 3.99%, 3.38%, and 8.46%, respectively,

and increased carbon dioxide emissions by 5.60%, 2.25%, 11.73%, and 4.96%, respectively, compared tothe emissions induced by B0. M. oleifera oil is a potential feedstock for biodiesel production, and theperformance of MB5 and MB10 biodiesel is comparable to that of PB5 and PB10 biodiesel and dieselfuel. Because the MB5 and MB10 fuels produce lower exhaust emissions than diesel fuel, these fuels canreplace diesel fuel in unmodified engines to reduce the global energy demand and exhaust emissions tothe environment.

. Introduction

Most energy consumed (87%) is derived from fossil fuels, tohich crude oil contributes 33.06%, coal 30.34%, and natural gas

3.67% (BP, 2012). The dominance of fossil fuels is primarily due tohe fuels’ adaptability, high combustion efficiency, availability, reli-bility, and handling facilities (de Vries, 2008; Mofijur et al., 2013a).owever, the reserves of fossil fuels are diminishing; meanwhile,

heir demand increases every day. However, emissions producedy the combustion of fossil fuels have adverse effects on the envi-

onment and human health. It is predicted that greenhouse gasGHG) emissions from fossil fuels will increase by 39% in 2030 ifo significant efforts are undertaken to alleviate them. Numerous

∗ Corresponding author. Tel.: +6 3 79674448; fax: +6 3 79674448.E-mail addresses: mofijduetme@yahoo.com, mofijduetme@gmail.com

M. Mofijur).

926-6690/$ – see front matter © 2013 Elsevier B.V. All rights reserved.ttp://dx.doi.org/10.1016/j.indcrop.2013.12.011

© 2013 Elsevier B.V. All rights reserved.

factors such as the depletion of petroleum-derived fuels, the threatof climate change, and increasing prices of petroleum products havemotivated researchers to seek alternative energy sources (Lim andTeong, 2010; Jayed et al., 2011; Atabani et al., 2012). Therefore, forseveral decades, many researchers have been developing new alter-native energy sources that are readily available, technically feasible,economically viable, and environmentally friendly. Biofuel is a fea-sible, clean alternative energy source that does not contain anyharmful substances and produces fewer harmful emissions thandiesel fuel (Mofijur et al., 2013b; Silalertruksa et al., 2012). Biodieselis one of the best biofuels that can reduce the global dependency onfossil-based diesel fuels and the emissions of environmental pol-lutants without requiring the modification of vehicles. Biodieselis non-explosive, biodegradable, non-flammable, renewable, non-

toxic, and environmentally friendly, and it has properties thatare similar to those of diesel fuel (Ávila and Sodré, 2012; Amaniet al., 2013; Thomas et al., 2013). Biodiesel can be obtained byapplying transesterification processes to vegetable oils, animal fats,

M. Mofijur et al. / Industrial Crops and Products 53 (2014) 78– 84 79

Nomenclature

ASTM American Society for Testing and MaterialsBP brake powerBSFC brake specific fuel consumptionCMOO crude Moringa oleifera oilCPO crude palm oilCO carbon monoxideCO2 carbon dioxideHC hydrocarbonPOME palm oil methyl estermm millimeterMJ/kg megajoule/kgMOME Moringa oleifera methyl esterNO nitric oxideNOx oxides of nitrogen

ueopatplusop

1

mursawai

iMosh

1

Ddee2nim(te

Table 1Properties of crude Palm oil (CPO) and Crude Moringa Oleifera oil (CMOO).

Properties Units Standards CPO CMOO

Dynamic viscosity mPa s ASTM D445 36.30 38.90Kinematic viscosity at 40 ◦C mm2/s ASTM D445 40.40 43.33Kinematic viscosity at 100 ◦C mm2/s ASTM D445 8.43 8.91Viscosity Index – N/A 192.1 193.1Density kg/m3 ASTM D4052 898.4 897.5Flash point ◦C ASTM D93 165 268.5Pour point ◦C ASTM D97 9 11Cloud point ◦C ASTM D2500 8 10

PM particulate matterrpm revolution per minute

sed cooking oil, and waste grease from restaurants (Vedaramant al., 2012; Wazilewski et al., 2013). The most common sourcesf biodiesel are edible oils (palm, rapeseed, sunflower, coconut,eanut, soybean etc.). It has been reported that edible-oil biodieselsre limited in their ability to contribute to climate change mitiga-ion and economic growth and serve as a substitute for petroleumroduction. The mass production of edible-oil biodiesels would

eads to food price increases and would create pressure on landse, making it unsustainable. Recently, non-edible-oil feedstocksuch as Jatropha curcas, Moringa oleifera, Pongamia pinnata, rubberil, and cotton-seed oil have attracted world-wide attention for theroduction biodiesel.

.1. Botanical description of palm and Moringa oleifera feedstocks

The palm tree reaches an average height of 20 m or more ataturity. The biophysical limits of the tree are as follows: altitude:

p to 900 m, mean annual temperature: 27–35 ◦C, and mean annualainfall: 2000–3000 mm. The root system consists of primary andecondary roots in the top 140 cm of soil. Leaves can reach 3–5 m indult trees. Leaf blades have numerous (100–160 pairs) long leafletsith prominent midribs that taper to a point; these leaflets are

rranged in groups or singly along the midrib, sometimes occurringn different planes.

M. oleifera, a member of the Moringaceae family, grows mainlyn tropical countries and is a drought-tolerant species. The seeds of

. oleifera are triangular in shape and contain approximately 40%il by weight (Atabani et al., 2013a,b). The oil produced from theeed kernel of M. oleifera is golden yellow in color. Recent studiesave indicated that M. oleifera is native to Malaysia.

.2. Objectives of the paper

Recently, many studies (Kalam and Masjuki, 2008; Patil andeng, 2009; Safieddin Ardebili et al., 2011) concerning the pro-uction of biodiesel from edible oil and its use as a fuel for dieselngines have been published. In addition, a few authors (Rashidt al., 2008; da Silva et al., 2010; Kafuku et al., 2010; Rashid et al.,011) have discussed the potential production of biodiesel fromon-edible oils such as palm and M. oleifera oil. However, there

s no report that provides a comparative evaluation of the perfor-

ance of palm and M. oleifera biodiesel blends in diesel engines

Rahman et al., 2013). Only Rajaraman et al. (2009) has reported onhe performance and emission characteristics of M. oleifera methylster and its blends (B20-B100) in a diesel engine under various load

Calorific value MJ/kg ASTM D240 39.44 38.05Acid value mgKOH/g oil ASTM D664 3.47 8.62

conditions. The authors reported that, compared to diesel fuel, M.oleifera methyl ester blends exhibit lower brake thermal efficiency(BTE) because of their lower heating value and higher viscosityand density than diesel fuel. With respect to engine emissions, M.oleifera methyl ester blends produce lower HC, CO, and PM emis-sions but higher NOx emissions compared to diesel fuel. Therefore,the primary objective of this study was to examine non-edible oilsources, such as M. oleifera, as a potential feedstock for biodieselproduction. In this investigation, a mixture of 5% palm and 5% M.oleifera oil with 95% diesel fuel was selected as a B5 reference fuel toimprove its physic-chemical properties and assess its performancein a diesel engine, as is suggested by the Malaysian government.

2. Materials and methods

2.1. Materials

Crude palm oil (CPO) was collected from the Forest ResearchInstitute, Malaysia (FRIM), and M. oleifera oil (CMOO) was gener-ously supplied by a colleague (personal communication). All otherchemicals, reagents, and accessories were purchased from localmarkets. Table 1 shows the properties of CPO and CMOO.

2.2. Production of palm and Moringa oleifera methyl esters

Palm and M. oleifera methyl esters were produced at the energylaboratory of the University of Malaya using a 1-L batch reactor, areflux condenser, a magnetic stirrer, a thermometer, and a samp-ling outlet. To produce palm biodiesel, crude palm oil was reactedwith 25% (v/v oil) methanol and 1% (m/m oil) potassium hydrox-ide (KOH) and maintained at 60 ◦C for 2 h and a stirring speedof 400 rpm. After the completion of the reaction, the producedbiodiesels were deposited in a separation funnel for 15 h to sep-arate glycerol from biodiesel. The lower layer, which containedimpurities and glycerol, was drawn off. M. oleifera methyl esterwas produced using an acid-base catalyst process. Before initiat-ing the esterification process, the crude M. oleifera oils were heatedto 60 ◦C using a temperature-controlled rotary evaporator (IKA)under vacuum to remove moisture. For the esterification process, a12:1 molar ratio of methanol to crude oil and 1% (v/v) sulfuric acid(H2SO4) were added to the preheated oil and stirred at 600 rpmand 60 ◦C for 3 h. Then, the esterified oil was separated from theexcess alcohol, sulfuric acid, and impurities using a separator fun-nel. The separated esterified oil was then heated to 60 ◦C in therotary evaporator for 1 h to remove the methanol and water. Forthe transesterification reaction, a 6:1 molar ratio of methanol to oiland 1% (m/m oil) potassium hydroxide (KOH) were mixed with thepreheated esterified oil and stirred at a constant speed of 600 rpm

at 60 ◦C temperature for 2 h. After the reaction was complete, themethyl ester was kept in a separation funnel for 24 h. Then, theglycerol in the lower layer was drained out, and the methyl esterwas washed with warm distilled water (3 times), dried in the rotary

80 M. Mofijur et al. / Industrial Crops and Products 53 (2014) 78– 84

Table 2Equipment list.

Property Equipment Manufacturer Test method

Kinematic viscosity SVM 3000 (Anton Paar, UK) ASTM D445Density SVM 3000 (Anton Paar, UK) ASTM D1298Oxidation stability 873 Rancimat (Metrohm, Switzerland) EN ISO 14112Flash point Pensky-martens flash point—automatic NPM 440 (Norma lab, France) ASTM D93Cloud and pour point Cloud and Pour point tester—automatic NTE 450 (Norma lab, France) ASTM D2500, ASTM D97Cold filter plugging point Cold filter plugging point tester—automatic NTL 450 (Norma lab, France) ASTM D6371Caloric value C2000 basic calorimeter (IKA, UK) ASTM D240Viscosity index SVM 3000 (Anton Paar, UK) N/A

gine

efi

2

mstet

2

foap

2

smded4rTiwp

ative uncertainty in BSFC was determined using the linearizedapproximation method of uncertainty. Table 5 summarizes the val-ues of the measurement accuracy and the relative uncertainty of

Table 3Details specification of the engine.

Engine type 4 cylinder inline

Displacement (L) 2.5Cylinder bore × stroke (mm) 91.1 × 95Compression ratio 21:1Maximum engine speed (rpm) 4200Maximum power (kW) 78

Fig. 1. En

vaporator, and filtered using qualitative filter paper to collect thenal product.

.3. Analysis of fuel properties

The physico-chemical properties of the palm and M. oleiferaethyl esters were characterized according to the ASTM D6751

tandard method. Table 2 displays the equipment used in this studyo analyze the relevant physical and chemical properties of thesters and the test methods used to perform the analysis accordingo the ASTM D6751 standard.

.4. Biodiesel-diesel blending

The test fuels (POME and MOME) were blended with dieselor 20 min using a homogenizer operated at 2000 rpm. The heightf the homogenizer, which was clamped to a vertical stand, wasdjustable. The fuels were mixed by homogenizing at the appro-riate speed.

.5. Engine tests

This experimental investigation was carried out using five fuelamples: diesel fuel (B0), the MB5 (95% diesel and 5% M. oleiferaethyl ester) blend, the PB5 (5% Palm oil methyl ester and 95%

iesel) blend, the MB10 (90% diesel and 10% M. oleifera methylster) blend, and the PB10 (10% Palm oil methyl ester and 90%iesel) blend. The test engine was a Mitsubishi Pajero (modelD56 T) multi-cylinder diesel engine. Fig. 1 shows the engine testig. The detailed specifications of the engine are listed in Table 3.

he engine was run with diesel fuel for several minutes to warmt up before the biodiesel fuels were tested. Likewise, the engine

as operated with diesel fuel before it was shut down. The samerocedure was used for each fuel test. To carry out engine

test bed.

performance and emission tests, the engine was run fully loaded atvarious speeds between 1000 and 4000 rpm and followed the SAEJ1515 MAR88 procedure. The engine test conditions were mon-itored by an REO-DCA controller connected through a desktopcomputer to the engine test bed (Fig. 1). A BOSCH exhaust gas ana-lyzer (model BEA-350) was used to measure the NO, HC, CO, andCO2 emissions. The specifications of this gas analyzer are presentedin Table 4. Every test was repeated three times, and the results wereaveraged.

2.6. Error analysis

Errors and uncertainties in experiments can arise from instru-ment selection, condition, calibration, environment, observation,reading, and test planning. Uncertainty analysis is needed to deter-mine the accuracy of experiments. In this study, the accuracies ofthe speed, fuel, brake power, and time measurements was ±10 rpm,±1% of the reading, ±0.07 kW, and ±0.1 s, respectively. The rel-

Fuel system Distribution type jet pump (indirect injection)Lubrication system Pressure feedCombustion chamber Swirl typeCooling system Radiator cooling

M. Mofijur et al. / Industrial Crops and Products 53 (2014) 78– 84 81

Table 4Details of the exhaust gas analyzer.

Equipment Method Measurement Upper limit Accuracy

BOSCH gas analyser Non-dispersive infrared CO 10.00 vol% ±0.001 vol%Non-dispersive infrared CO2 18.00 vol% ±0.01 vol %Flame ionization detector

Electro-chemical transmitter

Table 5Summary of measurements uncertainty.

Measurements Accuracy Relative uncertainty

BP ±0.07 kW ±0.243BSFC ± g/kW h ±0.013CO ±0.001 vol% ±0.003

vs

3

3a

(ccatoAmtd

3

bT

3

a

NO ±1 ppm ±0.005HC ±1 ppm ±0.090CO2 ±0.01 vol% ±0.001

arious parameters, including BP, BSFC, CO, HC, NO, and CO2 emis-ions.

. Results and discussion

.1. Characterization of palm and Moringa oleifera methyl esternd their blends

To characterize the pure palm and M. oleifera methyl estersB100), properties such as the density, flash point, kinematic vis-osity, viscosity index, calorific value, the cold filter plugging point,loud and pour points, and oxidation stability were examinednd compared with the ASTM D6751 standards. Table 6 showshe detailed physico-chemical characteristics of the palm and M.leifera methyl esters and their 5% by volume blends (PB5 and MB5).ll of the physico-chemical properties of the palm and M. oleiferaethyl esters met the ASTM D6751 and EN 14214 standards. Thus,

he palm and M. oleifera methyl esters can be used in unmodifiediesel engines.

.2. Engine performance

In this study, engine performance was evaluated in terms of therake power (BP) and the brake specific fuel consumption (BSFC).he details of this evaluation are discussed in the following sections.

.2.1. Brake power (BP)Fig. 2 shows the engine brake power (BP) output of the palm

nd M. oleifera methyl ester blends at different engine speeds. For

0

5

10

15

20

25

30

35

40

4000350030002500200015001000

Brak

e po

wer

[kW

]

Engine speed [rpm]

B0

PB5

MB5

PB10

MB10

Fig. 2. Variation in the brake power with respect to the engine speed.

HC 9999 ppm ±l ppmNO 5000 ppm ±1 ppm

all tested fuels, the brake power increased steadily with the enginespeed up to 3500 rpm and then decreased due to the increasing fric-tional force. At all test speeds, the average brake powers of the B0,PB5, MB5, PB10, and MB10 fuels were 28.72, 28.32, 28.07, 27.81, and27.51 kW, respectively. Compared to the brake power of diesel fuel,the PB5 and MB5 fuels produced lower brake powers (1.38, 2.27,3.16, and 4.22%, respectively) due to their lower calorific valuesand higher viscosities (Table 6), which affected their combustion.The uneven combustion characteristics of biodiesel fuel reducedthe engine brake power (Muralidharan and Vasudevan, 2011).

3.2.2. Brake specific fuel consumption (BSFC)Fig. 3 illustrates the variation in the BSFC values for all fuels

at different engine speeds. Each biodiesel blended fuel exhibiteda higher BSFC value than that of diesel fuel. This observation isconsistent with the results reported in the literature (Kalam et al.,2011; Chauhan et al., 2012; Wang et al., 2013). Factors such as thevolumetric fuel injection system, fuel density, viscosity, and lowerheating value affect the BSFC of diesel engines (Qi et al., 2010a). Atall speeds, the average BSFCs for the B0, PB5, MB5, PB10, and MB10blends were 385.71, 388.4, 395.40, 393.54, and 405.51 g/kW h,respectively. Per kW of power produced, more biodiesel blend isconsumed than diesel fuel because the calorific value of biodieselis lower than that of diesel fuel. Compared to the BSFC of diesel fuel,the BSFCs were 0.69, 2.56, 2.02, and 5.13% higher for the PB5, MB5,PB10, and MB10 blends, respectively. The blends’ BSFCs were higherbecause their densities and viscosities are higher and their energydensities are lower than those of diesel fuel (Mofijur et al., 2013c).Both the viscosity and the BSFC of the MB5 blend were higher thanthose of the PB5 blend (Table 6).

3.3. Emissions analysis

3.3.1. CO emissionsThe incomplete combustion of a fuel and the emission of CO are

due to insufficient molecular oxygen content in the fuel. Generally,factors such as the air-fuel ratio, engine speed, injection timing andpressure, and fuel type affect CO emissions (Gumus et al., 2012).The variation in CO emissions with the type of fuel used is shown

100

150

200

250

300

350

400

450

500

550

4000350030002500200015001000

BSFC

[g/k

Wh]

Engine spee d [rpm]

B0

PB5

MB5

PB10

MB10

Fig. 3. Variation in the brake specific fuel consumption with respect to the enginespeed.

82 M. Mofijur et al. / Industrial Crops and Products 53 (2014) 78– 84

Table 6Physico-chemical properties of Palm and Moringa oleifera methylester and their blend.

Properties Units B0 MOME POME PB5 PB10 MB5 MB10 ASTM D6751 EN 14214

Dynamic viscosity Pa s 2.69 4.34 4.09 2.77 2.84 2.81 2.94 – –Kinematic viscosity at 40 ◦C mm2/s 3.23 5.05 4.73 3.31 3.39 3.39 3.55 1.9–6 3.5–5Kinematic viscosity at 100 ◦C mm2/s 1.24 1.84 1.81 1.29 1.33 1.30 1.36 – –Density kg/m3 827.2 869.6 865.7 828.7 837.9 829.6 830.6 – 860–900Flash point ◦C 68.5 150.5 184.5 74.5 77.5 74 79.5 130 min 120 minCloud point ◦C 8 19 3 8 8 7 7 – –Pour point ◦C 0 19 3 0 1 3 3 – –Cold filter plugging point ◦C 5 18 10 5 6 6 6 – –Calorific value MJ/kg 45.30 40.05 39.82 44.70 44.50 45.03 44.75 – –Iodine value g I/100 g – 77.5 99 – – – – – 120 max

iaCtatTmeae

3

fdMd

Fa

Saponification value – – 199 202

Oxidation stability h – 26.2 3.02

Cetane number – 48 56.3 51

n Fig. 4. Over the entire range of engine speeds, the PB5, MB5, PB10,nd MB10 blends showed 13.17%, 5.37%, 17.36%, and 10.60% lowerO emissions than B0, respectively. This result is consistent withhe literature ( Lapuerta et al. (2008); Kim and Choi, 2010; Hirkudend Padalkar, 2012). This reduction in CO emissions is attributed tohe higher oxygen content and cetane number of biodiesel fuel.he higher oxygen content of biodiesel allows for more carbonolecules to burn and thus complete fuel combustion. Thus, CO

missions are lower when diesel engines burn biodiesel fuel. Inddition, at half load condition biodiesel blended fuels lowered COmissions by (10–23.5%) than B0 fuel.

.3.2. HC emissionsUnburned HC is the result of the incomplete combustion of

uels and flame quenching. The variation in HC emissions for theiesel and biodiesel blend fuels is shown in Fig. 5. For the PB5 andB5 blends, the unburned HC emissions were lower than those for

iesel fuel. Over the entire range of speeds, the average reductions

(a)

(b)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

100 0 150 0 2000 2500 3000 35 00 40 00

CO E

mis

sion

s [vo

l %]

Engine spee d [rpm]

B0

MB5

PB5

MB10

PB10

00.10.20.30.40.50.60.70.80.9

1

100 0 150 0 2000 2500 3000 35 00 40 00

CO E

mis

sion

[vol

%]

Engine spee d [rpm]

B0

MB5

MB10

PB5

PB10

ig. 4. Variation in CO emissions with respect to the engine speed (a) at full load (b)t half load.

– – – – – –– – – – 3 6– – – – 47 min 51 min

in HC emission for the PB5, MB5, PB10, and MB10 were 14.47%,3.94%, 18.42%, and 9.21% relative to B0, respectively. These reduc-tions are attributed to the high oxygen contents of these biodieselfuels. Biodiesel contains more oxygen and less carbon and hydro-gen than diesel fuel, which guarantees more complete combustion(Lin et al., 2009; Qi et al., 2010b). On the other hand, HC emissionwas decreased with increasing the load of the engine.

3.3.3. NO emissionsThe variation in the NO emissions for the diesel and biodiesel

blend fuels is shown in Fig. 6. The NO values were higher forthe biodiesel blends than for the diesel fuel. This result is con-sistent with studies published by other researchers (El-Kasabyand Nemit-allah, 2013). On average, the PB5, MB5, PB10, and

MB10 blends produced 1.96%, 3.99%, 3.38%, and 8.46% higher NOemissions, respectively, than the diesel fuel over the entire rangeof speeds. Also, at half load condition biodiesel blended fuelsincreased NO emissions by (10.38–16.50%) than B0 fuel. This result

(a)

(b)

02468

101214161820

1000 1500 2000 2500 3000 3500 4000

HC E

mis

sion

[ppm

]

Engine speed [rpm]

B0

MB5

PB5

MB10

PB10

02468

101214161820

1000 1500 2000 2500 3000 3500 4000

HC E

mis

sion

[ppm

]

Engi ne s pee d [rpm ]

B0

MB5

MB10

PB5

PB10

Fig. 5. Variation in HC emissions with respect to the engine speed (a) at full load (b)at half load.

M. Mofijur et al. / Industrial Crops a

(a)

(b)

0

50

100

150

200

250

300

100 0 15 00 2000 250 0 30 00 3500 400 0

NO

Em

issi

on [p

pm]

Engine spee d [rpm]

B0

PB5

MB5

PB10

MB10

0

50

100

150

200

250

300

100 0 15 00 2000 250 0 30 00 3500 400 0

NO

Em

issi

on [p

pm]

Engine spee d [rpm]

B0

MB5

MB10

PB5

PB10

Fig. 6. Variation in NO emissions with respect to the engine speed (a) at full load(b) at half load.

(a)

(b)

0

2

4

6

8

10

12

1000 150 0 200 0 250 0 300 0 350 0 40 00

CO2

Emis

sion

[vol

%]

Engine speed [rpm]

B0

MB5

PB5

MB10

PB10

0

2

4

6

8

10

12

14

1000 150 0 200 0 250 0 300 0 350 0 40 00

CO2

Emis

sion

[vol

%]

Engine spped [rpm]

B0

MB5

MB10

PB5

PB10

Fig. 7. Variation in CO2 emissions with respect to the engine speed (a) at full load(b) at half load.

nd Products 53 (2014) 78– 84 83

can be attributed to the leaner air/fuel ratio of the blends—biodieselis an oxygenated fuel that contains 12% more molecular oxygenthan diesel—which raises the chamber temperature and improvescombustion (Devan and Mahalakshmi (2009)). Thus, NO emissionswere higher for the biodiesel blends than for the diesel fuel. More-over, the higher NO emissions may be attributed to the higheradiabatic flame temperature of the blends. Biodiesel fuels that con-tain more unsaturated fatty acids exhibit higher adiabatic flametemperatures, which cause higher NO emissions (El-Kasaby andNemit-allah, 2013).

3.3.4. CO2 emissionsThe variation in CO2 emissions for all of the fuel samples at var-

ious speeds are shown in Fig. 7. When the engine speed increased,the CO2 emissions also increased. The biodiesel fuel blends PB5,MB5, PB10, and MB10 on average produced 5.60%, 2.25%, 11.73%,and 4.96% more CO2 emissions than the diesel fuel, respectively.It was also found that at half load condition biodiesel blended fuelincreased CO2 emission by (6–15%) than diesel fuel. The produc-tion of carbon dioxide from the combustion of fossil fuels causesmany environmental problems such as the accumulation of carbondioxide in the atmosphere. Although biofuel combustion producescarbon dioxide, absorption by crops helps to maintain CO2 levelsconstant (Ramadhas et al. (2005)).

4. Conclusions

In this study, biodiesel was produced from crude palm and M.oleifera oils, and the performance of 5% and 10% biodiesel blends byvolume in a diesel engine was evaluated. Based on this experimen-tal study, the following conclusions are drawn:

• The physico-chemical properties of the Palm and M. oleiferamethyl esters and their blends meet the ASTM D6751 and EN14214 standards.

• Over the entire range of engine speeds examined, the PB5, MB5,PB10, and MB10 biodiesels yielded average brake powers of28.32, 28.07, 27.81, and 27.51 kW, which were 1.38, 2.27, 3.16,and 4.22% lower than the average brake power of the B0 fuel,respectively. The average brake specific fuel consumption valueswere 388.4, 395.40, 393.54, and 405.51 g/kW h for the PB5, MB5,PB10, and MB10 blends, respectively, which were slightly higher(0.69, 2.56, 2.02, and 5.13%) than the average BSFC of the B0 fuel.These results are attributed to the higher viscosity and densityand the lower energy content of these biodiesel blends.

• As diesel fuel substitutes, the PB5, MB5, PB10, and MB10 blendsreduced the average CO emissions of diesel fuel by 13.17%, 5.37%,17.36%, and 10.60%, respectively, and reduced the HC emissionsof diesel fuel by 14.47%, 3.94%, 18.42% and 9.21%, respectively.However, the PB5 and MB5 blends slightly increased the NOemissions of diesel fuel by 1.96%, 3.99%, 3.38%, and 8.46%, respec-tively. Moreover, the PB5, MB5, PB10, and MB10 increased theCO2 emissions of diesel fuel (by 5.60%, 2.25%, 11.73%, and 4.96%,respectively). These results are attributed to the higher oxygencontents and cetane numbers of the biodiesel blended fuels.

In conclusion, M. oleifera oil is a potential feedstock for biodieselproduction, and the performances of the MB5 and MB10 biodieselblends are comparable with those of the PB5 and PB10 biodiesel

blends and diesel fuel. Because the MB5 and MB10 blends reducedthe exhaust emissions of diesel fuel, these blends can replace dieselfuel in unmodified engines to reduce the global energy demand andexhaust emissions into the environment.

8 Crops

A

fG

R

A

A

A

A

Á

B

C

d

d

D

E

G

H

J

K

K

K

K

4 M. Mofijur et al. / Industrial

cknowledgments

The authors would like to acknowledge the University of Malayaor providing financial support through the High Impact Researchrant UM.C/HIR/MOHE/ENG/07.

eferences

mani, M.A., Davoudi, M.S., Tahvildari, K., Nabavi, S.M., Davoudi, M.S., 2013. Biodieselproduction from Phoenix dactylifera as a new feedstock. Ind. Crops Prod. 43,40–43.

tabani, A.E., Mahlia, T.M.I., Masjuki, H.H., Badruddin, I.A., Yussof, H.W., Chong, W.T.,Lee, K.T., 2013a. A comparative evaluation of physical and chemical propertiesof biodiesel synthesized from edible and non-edible oils and study on the effectof biodiesel blending. Energy 58, 296–304.

tabani, A.E., Silitonga, A.S., Badruddin, I.A., Mahlia, T.M.I., Masjuki, H.H., Mekhilef,S., 2012. A comprehensive review on biodiesel as an alternative energy resourceand its characteristics. Renewable Sustainable Energy Rev. 16, 2070–2093.

tabani, A.E., Silitonga, A.S., Ong, H.C., Mahlia, T.M.I., Masjuki, H.H., Badruddina,I.A., Fayaz, H., 2013b. Non-edible vegetable oils: a critical evaluation of oilextraction, fatty acid compositions, biodiesel production, characteristics, engineperformance and emissions production. Renewable Sustainable Energy Rev. 18,211–245.

vila, R.N.d.A., Sodré, J.R., 2012. Physical–chemical properties and thermal behaviorof fodder radish crude oil and biodiesel. Ind. Crops Prod. 38, 54–57.

P, 2012. Statistical Review of World Energy, 〈http://www.bp.com/assets/bp internet/globalbp/globalbp uk english/reports and publications/statistical energy review 2011/STAGING/local assets/pdf/statisticalreview of world energy full report 2011.pdf〉 (cited on 01/07/2013).

hauhan, B.S., Kumar, N., Cho, H.M., 2012. A study on the performance and emissionof a diesel engine fueled with Jatropha biodiesel oil and its blends. Energy 37,616–622.

a Silva, J.P.V., Serra, T.M., Gossmann, M., Wolf, C.R., Meneghetti, M.R., Meneghetti,S.M.P., 2010. Moringa oleifera oil: studies of characterization and biodiesel pro-duction. Biomass Bioenergy 34, 1527–1530.

e Vries, S.C., 2008. The bio-fuel debate and fossil energy use in palm oil production:a critique of Reijnders and Huijbregts 2007. J. Clean Prod. 16, 1926–1927.

evan, P.K., Mahalakshmi, N.V., 2009. A study of the performance, emission andcombustion characteristics of a compression ignition engine using methyl esterof paradise oil-eucalyptus oil blends. Appl. Energy 86, 675–680.

l-Kasaby, M., Nemit-allah, M.A., 2013. Experimental investigations of ignition delayperiod and performance of a diesel engine operated with Jatropha oil biodiesel.Alexandria Eng. J. 52, 141–149.

umus, M., Sayin, C., Canakci, M., 2012. The impact of fuel injection pressure on theexhaust emissions of a direct injection diesel engine fueled with biodiesel–dieselfuel blends. Fuel 95, 486–494.

irkude, J.B., Padalkar, A.S., 2012. Performance and emission analysis of a compres-sion ignition: Engine operated on waste fried oil methyl esters. Appl. Energy 90,68–72.

ayed, M.H., Masjuki, H.H., Kalam, M.A., Mahlia, T.M.I., Husnawan, M., Liaquat,A.M., 2011. Prospects of dedicated biodiesel engine vehicles in Malaysia andIndonesia. Renewable Sustainable Energy Rev. 15, 220–235.

afuku, G., Lam, M.K., Kansedo, J., Lee, K.T., Mbarawa, M., 2010. Heterogeneous cat-alyzed biodiesel production from Moringa oleifera oil. Fuel Process. Technol. 91,1525–1529.

alam, M.A., Masjuki, H.H., 2008. Testing palm biodiesel and NPAA additives to con-trol NOx and CO while improving efficiency in diesel engines. Biomass Bioenergy32, 1116–1122.

alam, M.A., Masjuki, H.H., Jayed, M.H., Liaquat, A.M., 2011. Emission and perfor-

mance characteristics of an indirect ignition diesel engine fuelled with wastecooking oil. Energy 36, 397–402.

im, H., Choi, B., 2010. The effect of biodiesel and bioethanol blended diesel fuelon nanoparticles and exhaust emissions from CRDI diesel engine. RenewableEnergy 35, 157–163.

and Products 53 (2014) 78– 84

Lapuerta, M., Armas, O., Rodríguez, F.J., 2008. Effect of biodiesel fuels on diesel engineemissions. Prog. Energy Combust. Sci. 34, 198–223.

Lim, S., Teong, L.K., 2010. Recent trends, opportunities and challenges of biodieselin Malaysia: an overview. Renewable Sustainable Energy Rev. 14, 938–954.

Lin, B.-F., Huang, J.-H., Huang, D.-Y., 2009. Experimental study of the effects of veg-etable oil methyl ester on DI diesel engine performance characteristics andpollutant emissions. Fuel 88, 1779–1785.

Mofijur, M., Atabani, A.E., Masjuki, H.H., Kalam, M.A., Masum, B.M., 2013a. A studyon the effects of promising edible and non-edible biodiesel feedstocks on engineperformance and emissions production: a comparative evaluation. RenewableSustainable Energy Rev. 23, 391–404.

Mofijur, M., Masjuki, H.H., Kalam, M.A., Atabani, A.E., Shahabuddin, M., Palash, S.M.,Hazrat, M.A., 2013b. Effect of biodiesel from various feedstocks on combustioncharacteristics, engine durability and materials compatibility: a review. Renew-able Sustainable Energy Rev. 28, 441–455.

Mofijur, M., Masjuki, H.H., Kalam, M.A., Atabani, A.E., 2013c. Evaluation of biodieselblending, engine performance and emissions characteristics of Jatropha curcasmethyl ester: Malaysian perspective. Energy. 55, 879–887.

Muralidharan, K., Vasudevan, D., 2011. Performance, emission and combustion char-acteristics of a variable compression ratio engine using methyl esters of wastecooking oil and diesel blends. Appl. Energy 88, 3959–3968.

Patil, P.D., Deng, S., 2009. Optimization of biodiesel production from edible and non-edible vegetable oils. Fuel 88, 1302–1306.

Qi, D.H., Chen, H., Geng, L.M., Bian, Y.Z., 2010a. Experimental studies on the com-bustion characteristics and performance of a direct injection engine fueled withbiodiesel/diesel blends. Energy Convers. Manage. 51, 2985–2992.

Qi, D.H., Chen, H., Geng, L.M., Bian, Y.Z., Ren, X.C., 2010b. Performance and combus-tion characteristics of biodiesel–diesel–methanol blend fuelled engine. Appl.Energy 87, 1679–1686.

Rahman, M.M., Hassan, M.H., Kalam, M.A., Atabani, A.E., Memon, L.A., Rahman,S.M.A., 2013. Performance and emission analysis of Jatropha curcas and Moringaoleifera methyl ester fuel blends in a multi-cylinder diesel engine. J. CleanerProd..

Rajaraman, S., Yashwanth, G.K., Rajan, T., Kumaran, R.S., Raghu, P., 2009. Experi-mental investigations of performance and emission characteristics of Moringaoil methyl ester and its diesel blends in a single cylinder direct injection dieselengine. In: Proceedings of the ASME 2009 International Mechanical EngineeringCongress & Exposition, November 13-19, Lake Buena Vista, FL, USA.

Ramadhas, A.S., Muraleedharan, C., Jayaraj, S., 2005. Performance and emission eval-uation of a diesel engine fueled with methyl esters of rubber seed oil. RenewableEnergy 30, 1789–1800.

Rashid, U., Anwar, F., Ashraf, M., Saleem, M., Yusup, S., 2011. Applica-tion of response surface methodology for optimizing transesterification ofMoringa oleifera oil: biodiesel production. Energy Convers. Manage. 52,3034–3042.

Rashid, U., Anwar, F., Moser, B.R., Knothe, G., 2008. Moringa oleifera oil: a possiblesource of biodiesel. Bioresour. Technol. 99, 8175–8179.

Safieddin Ardebili, M., Ghobadian, B., Najafi, G., Chegeni, A., 2011. Biodiesel produc-tion potential from edible oil seeds in Iran. Renewable Sustainable Energy Rev.15, 3041–3044.

Silalertruksa, T., Bonnet, S., Gheewala, S.H., 2012. Life cycle costing and externalitiesof palm oil biodiesel in Thailand. J. Cleaner Prod. 28, 225–232.

Thomas, T.P., Birney, D.M., Auld, D.L., 2013. Optimizing esterification of saf-flower, cottonseed, castor and used cottonseed oils. Ind. Crops Prod. 41,102–106.

Vedaraman, N., Puhan, S., Nagarajan, G., Ramabrahmam, B.V., Velappan, K.C., 2012.Methyl ester of Sal oil (Shorea robusta) as a substitute to diesel fuel—a study onits preparation, performance and emissions in direct injection diesel engine. Ind.Crops Prod. 36, 282–288.

Wang, D., Ling, X., Peng, H., Liu, L., Tao, L., 2013. Efficiency and optimal performance

evaluation of organic Rankine cycle for low grade waste heat power generation.Energy 50, 343–352.

Wazilewski, W.T., Bariccatti, R.A., Martins, G.I., Secco, D., Souza, S.N.M.d., Rosa, H.A.,Chaves, L.I., 2013. Study of the methyl crambe (Crambe abyssinica Hochst) andsoybean biodiesel oxidative stability. Ind. Crops Prod. 43, 207–212.