St. Pauls Convent SchoolGreen Saviour Chitin and Chitosan

Solutions to water pollution Chitin ChitosanMetal ions

grease

dyes

Chitin-second most abundant natural polysaccharide

crustaceans

insects

molluscs

fungi

Chitin-second most abundant natural polysaccharide

Structure of Chitin

Cleaving off acetyl group

Part IALobster

Extractionshrimp Three-spotted Crab

Chinese Mitten Crab

Big Head Prawn

Red Crab

Mantis Shrimp

7 crustacean shells

Abalone

Clam

Oyster

Needle Inkfish

Snail

Noble Scallop

Fan Shell

Japanese Scallop

Razor Clam

Green Mussel

11 mollucs

Mushroom stalks

Extract chitin from shell wastes Shells crushed into fine pieces Demineralization by dilute HCl Deproteinization by dilute NaOH

Extract chitin from mushroom stalks NaOH was added followed by ethanoic acid

Results-

Percentage Yield of Chitin from 7 Crustaceans50% 45% 40% 35% 30% 25% 20% 15% 10% 5% 0%Cr ab Cr ab Sh rim p Sh rim p Pr aw n Cr ab T hr ee -s po tte d M itt en Lo bs te r

Re d

He ad

Ch ine se

Bi g

M an tis

Results-

0%

1%

2%

3%

4%

5%

6%

Ne ed Ch le Ink ine fis se h My ste ry Sn ail

Pa cif Co ic mm Oy ste on r Or ien tal Cl am Fa nS he ll Gr ee nM us se l Ra zo rC Ja lam pa ne se Ab alo ne No ble Sc all Ja op pa ne se Sc all op

Percentage Yield of Chitin from 11 Molluscs

Th re Ch in e-s

10%

20%

30%

40%

50%

60%

70%

es eM it t e nC rab dC

Overall results-

po

0%

tte

Percentage yield of chitin from different resources

r Re ab dC rab Sh Bi gH rim ea p dP Ma raw nt i n sS hri mp Lo bs Ne Ch t er ed i ne le se Ink My fis s te h ry Sn ai l Pa Co c if mm ic on Oy Or s te i en r t al Cl F a am nS Gr he ee ll nM us Ra se l Ja zo pa rC ne l am se Ab a No bl e l one Ja Sc pa al l ne op Sh se iit a sc ke a M u l l op sh roo m

Part IB Alkaline Deacetylation

Lobster

Red Crab

Shrimp

Lobster

Red Crab

Shrimp

Chitin

Chitosan

Mantis shrimp

Needle inkfish

Mushroom

Mantis shrimp

Needle inkfish

Mushroom

Chitin was heated in concentrated NaOH under reflux

Percentage Yield of Chitosan from Original Source40.0%

30.0%

20.0%

10.0%

0.0%M us hr oo m Lo bs te r S hr im p S hr im p In kf is h N ee dl e C ra b R ed

M an tis

Part IIA Adsorption of Dyes5 Chitin Red Crab Chinese Mitten Crab Shrimp Lobster Mushroom

Congo Red

Safranine O

Gentian Violet Methyl Orange

Fast Green

Eosin Y

Malachite Green

Methylene blue

Control

Control

After 60 hours

After 180 hours

Gentian Violet with chitin and its control

Colorimeter to measure colour intensitiesGentian Violet Control Mushroom Lobster Red Crab Chinese Mitten Crab Shrimp After 60 hrs 42% 45% 44% 64% 76% 74% 3% 2% 22% 34% 32% Compare to Control After 180 hrs 42% 32% 66% 73% 84% 65% 10% 24% 31% 42% 23% Compare to Control

Mushroom

Lobster

Red Crab

Chinese Mitten Crab

Shrimp

Congo Red

Malachite Green

Eosin Y

Methylene Blue

Gentian Violet

Fast Green

Methyl Orange

Safranine O

Congo Red Control Mushroom Lobster Red Crab Chinese Mitten Crab Shrimp

After 60 hrs 2% 4% 10% 8% 21% 53%

Compare to Control

After 180 hrs 2%

Compare to Control

2% 8% 6% 19% 51%

7% 81% 64% 75% 82%

5% 79% 62% 73% 80%

The longer the chitin was allowed to stand, the more dye will be absorbed.

Application to daily life5 Chitin Shrimp Red Crab Chinese Mitten Crab Lobster Mushroom

Ink for bubble jet printers

Ink for Fountain pens

Transmission Percentage of Parker Ink in Colorimeter after treating with Chitin from different sources100% 90% 80% Transmission Percentage (%) 70% 60% 50% 40% 30% 20% 10% 0%l tro on C om hro s Mu ter bs Lo ab ab Cr Cr n d it t e Re eM es in Ch mp hri S

Percentage transmission increased

Types of dyes adsorbed by chitindyes found in laboratory

ink used in daily life

Shrimp Chinese mitten Crab chitin chitin

Shrimp chitin

Chinese mitten Crab chitin

Shrimp Chinese mitten chitin Crab chitin

Results further proved that Shrimp chitin and Chinese mitten crab Chitin were most effective in removing dyes.

Part IIB

Removal of Metal ions

Lobster Chitin

Red Crab ChitinRemove

Shrimp Chitin

Mushroom Chitin

Ni2+

Fe3+

Cu2+

Cr3+

Co2+

Colorimetric MeasurementCu2+ with chitin

Control

Mushroom Chitin

Red Crab Chitin

Lobster Chitin

Shrimp Chitin

Transmission % of Metal Ions in Colorimeter after treating with Chitin from Different Sources110% 100% Transmission Percentage (%) 90% 80% 70% 60% 50% 40% 30% 20% 10% 0%ControlMushroomLobsterRed CrabShrimp

Ni2+

Ni2+

Cu2+

Cu2+

Cr3+

Cr3+

Co2+

Co2+

Fe3+

Fe3+

There was NO significant fade in colour

Transmission Percentage of Metal Ions in Colorimeter after treating with Chitosan from Different Sources40% Transmission Percentage (%)

30%

20%Control

10%

LobsterRed CrabShrimpMushroom

0%

Ni2+

Cu2+

Cr3+

Co2+

Fe3+

Gravimetric Method60 hours Chitosan

Pb2+

Ni2+

Fe3+

Cu2+

Cr3+

Co2+

Zn2+

NaOH or Na2CO3 solution was added

Filter by suction

Result of Part IIBColorimetric Measurement

Consistent Result!Gravimetric Measurement More effective!

Adsorption and Chelation of metal ions by various chitosanLobster Red Crab Red crab Shrimp Shrimp Mushroom Mushroom

Ni2+ Ni2+Cu Cu2+ 2+

Cr3+Cr3+ Co2+ 2+ Co Fe3+Fe3+ Pb2+ 2+ Pb Zn2+ 2+ Zn

Part IIC

Adsorption of Grease

Lobster Chitin

Red Crab Chitin

Shrimp Chitin

Adsorb Grease!

Lobster Chitosan Red Crab Chitosan Shrimp Chitosan

Part IIC

Adsorption of Grease

Chitin and Chitosan were added

Test tubes were shaken

Part IIC

Adsorption of GreaseAfter shaking with 80 drops of oil

Lobster Chitin

Red Crab Chitin

Shrimp Chitin

Control

Lobster Chitosan

Red Crab Chitosan

Shrimp Chitosan

Chitosan - better adsorption power than chitin!

Adsorption of grease by chitin and chitosanLobster Chitin chitin Red Red Crab Chitin chitin Shrimp Shrimp Chitin chitin Lobster Chitosan chitosan Red Crab Red crab Chitosan chitosan

Shrimp Chitosan chitosan

Shrimp chitosan was the most effective!

Part III Filtration DeviceUpper compartmentSeparating disc with holes Hole for releasing treated water Hole for releasing pressure

Lower compartment

Part III Filtration DeviceRed crab chitosan Metal + ions Lobster chitosan + Shrimp chitosan oil + Chinese mitten crab chitin + dyes Shrimp chitin

Demonstration of the filtration device

Part III

Filtration Device

Chitin and Chitosan are reusable!After washing with dilute HCl

Chitin after adsorbing dyes

Recycled chitin

Part III

Filtration Device

You can simply discard chitin since it is biodegradable!

Our project is practicalReduce the volume of solid wastes

Our project is practicalChitin and chitosan produced can be used to treat water pollution

Our project is practical

In real situations, a more complex machine will be used Its basic mechanism will be similar to our design.

Our filtration device

ConclusionChitin and Chitosan are suitable for removing Dyes Metal ions Grease in waste water Advantages: Bio-degradable Non-toxic

ConclusionFurther Research

Recycling of wastes into Chitin and Chitosan become more economical and feasible

Green Savior Chitin and Chitosan

The EndBy St. Pauls Convent School

Principles of Green ChemistryLess Hazardous Chemical Synthesis excess acid and alkali can be neutralized to form harmless salt and water only.

NaOH + HCl

NaCl + H2O

Designing Safer Chemicals Chitin and Chitosan are useful and non-toxic

Principles of Green ChemistryDesign for Energy Efficiency extraction of Chitin and Chitosan can be done in room temperature and pressure Reduce Derivatives extraction of Chitin is a two-step process only Design for degradation Chitin and Chitosan are biodegradable

Factors affecting the adsorption ability Chitin of different forms (, , ) Chitin/chitosan from different sources may have different degree of deacetylation and different degree of polymerization Impurities present in the crude product (e.g. pigments like carotenoids)

Structural work on squid pen chitin has shown that these chitins are beta-chitins which have a much more open structure (parallel chain alignment) than the alphachitin (anti-parallel chain alignment) found in crustacean exoskeletons. Films made with squid chitosan were more elastic than crustacean chitosan with improved functional properties.

Glycoconjugate Journal (1997), 14, 535542

Production cost of chitosanCost of 2.5 dm3 of 12M HCl = HK$ 235 Cost of 1 kg of NaOH(s) = HK$ 55 Our production cost of 1 g of chitin < HK$ 1.5 1 g of chitosan < HK$ 2.5

Price value of 1 g commercially available chitosan: about $12 USD

Critical Review in Food Science and Nutrition (2003), 43, 145-171

Chinese Mitten Crab

Noble Scallop

Abalone

Fan Shell

Needle Inkfish

Critical Review in Food Science and Nutrition (2003), 43, 145-171

Factors affecting the chitin content the species peeling conditions during processing part of the organism state of their nutrition stage of reproductive cycle

Common Name Three-spotted Crab Chinese Mitten Crab A Chinese Mitten Crab B Red Crab Shrimp A Shrimp B Shrimp C Shrimp D Shrimp E Shrimp F Shrimp G Big Head Prawn Lobster A Lobster B Lobster C Lobster D Needle Inkfish A Needle Inkfish B

Chinese Name A B A B C D E F G A B C D A B

Mass of Shell Used (g) 18.61 40.81 37.92 112.89 9.18 7.59 5.68 4.57 8.18 6.70 18.46 27.95 48.73 89.96 51.97 30.32 84.08 69.48

Mass of Chitin Yielded (g) 2.65 8.42 8.46 41.80 3.20 2.08 1.99 1.54 2.20 1.60 4.42 8.44 14.82 52.69 30.47 12.87 1.65 1.65

% Yield 14.2% 20.6% 22.3% 37.0% 34.9% 27.4% 35.0% 33.7% 26.9% 23.9% 23.9% 30.2% 30.4% 58.6% 58.6% 42.4% 1.96% 2.37%

Ave % Yield

23.5%

29.5%

47.5%

2.17%

Innovative part of our project locally consumed seafood different sources have different chitin content different chitins/chitosans have different adsorption ability find the best combination of chitins & chitosans for filtration device remove dyes, metal ions and grease most effectively

Th re Ch in e-s

10%

20%

30%

40%

50%

60%

70%

es eM it t e nC rab dC

Overall results-

po

0%

tte

Percentage yield of chitin from different resources

r Re ab dC rab Sh Bi gH rim ea p dP Ma raw nt i n sS hri mp Lo bs Ne Ch t er ed i ne le se Ink My fis s te h ry Sn ai l Pa Co c if mm ic on Oy Or s te i en r t al Cl F a am nS Gr he ee ll nM us Ra se l Ja zo pa rC ne l am se Ab a No bl e l one Ja Sc pa al l ne op Sh se iit a sc ke a M u l l op sh roo m

Control

Suspended Particles

Gentian violet is used in microscopy as a biological stain and in medicine as a bactericide, fungicide, and anthelmintic. Fast Green is a food dye used for tinned green peas and other vegetables, jellies, sauces, fish, desserts, and dry bakery mixes Safranine O is an orange-red nitrogenous dyestuff produced artificially by oxidizing certain aniline derivatives, and used in dyeing silk and wool

Malachite green is used to dye materials like silk, leather, and paper. Congo red is used as a dye, indicator, and biological stain. It has a strong, though apparently non-covalent affinity to cellulose fibres. Methylene blue is used as a dye for Gram's stain, Wright's stain, and Jenner's stain. Eosin Y is an acidic dye and shows up in the basic parts of the cell, ie the cytoplasm. Methyl Orange is a pH indicator frequently used in titrations. It is also toxic.

Water Treatment: Water Purification As a polymer, chitosan's natural tendency is to form long chains of molecules with positive charges, which act like hooks. These natural hooks catch organic materials, such as oils, detergents, and other contaminants suspended in water. The material then coagulates to form flakes that are easily filtered out. Filtration companies are using chitin in clarifiers to help filter particulates and chemicals from water. Wastewater Treatment In Japan, chitosan was first used for wastewater treatment because of its metal-binding properties. It is also good for cleaning up toxic organic compounds, such as PCBs.

Uses of ChitinMedical Application anti-bacterial sponges, artificial blood vessels, contact lenses, blood cholesterol control and diapers Water Treatment metal-binding properties, catch organic materials, such as oils, detergents, and other contaminants suspended Dietary Supplements significantly bind fat, acting like a sponge in the digestive tract. Cosmetics Make-up powder; nail polish; moisturizers; face, hand, and body creams; and toothpaste Agriculture Seeds treated with chitosan are larger and stronger and more resistant to fungal diseases.

Interaction between different functional groupsDyesAmino group (NH2/NR2) Sulphonate group (SO3)

ChitinHydroxyl group (OH) Amide group (NHCO)

Cationic dye

Anionic dye

They form strong ion-dipole interactions with the polar groups of chitin

Part IIBChitin

Removal of Metal ions

VS

Structure of Chitin

ChitosanMushroom Structure of Chitosan

Chemical PrincipleInteractions of metal ions with chitosan: Adsorption Chelation

Dative covalent bonds

Vacant dorbitals of central metal ions

Lone pair of electrons

Chemical PrincipleAdsorption and Chelation

Complex ion

Chemical Principle

Structure of Chitin

H-bond or dipole-dipole interactionStructure of a fat molecule

Structure of Chitosan

VALUE PRICE US$15.59 (120 capsules)

Preparation of chitin and chitosan

Weifang Kehai Chitosan Co. Ltd.

Main ReferenceCHITIN CHEMISTRY by George A.F. Roberts Publisher: MACMLLAN (1992)

Journal of Agricultural and Food Chemistry (2005), 53, 3888-3894