Utilization of Chitosan Prepared From Seafood Industry Waste

8/3/2019 Utilization of Chitosan Prepared From Seafood Industry Waste

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Utilization of Chitosan Prepared from Seafood Industry Waste

to Clean up Oil Spills

Document By: Bharadwaj

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Abstract

Now-a-days oil spills are major environmental problem faced by petroleum industries. In the

present study, adsorbent (Chitosan) was prepared from the seafood industry waste, prawn shells

for removal of oil from aqueous solution. Chitin is obtained from the deprotination and

demineralization of shells. Chitin on deacetylation using 40 wt% Sodium hydroxide (NaOH)

gives chitosan. Batch experiments are carried out to see the effect significant parameters such as

initial concentration and contact time for the removal of oil from oil-water solutions using

chitosan. The equilibrium time for adsorption of oil from oil-water solution using chitosan is

obtained as 6 min which is relatively short. The maximum capacity of chitosan to adsorb oil

from oil-water solution is found as 17.96 g/g of adsorbent.

Keywords: Prawn shells; Chitosan; Oil spills; Adsorption; Batch studies.

1. Introduction

An oil spill is the release of a liquidpetroleumhydrocarbon into the environment due to human activity,

and is a form ofpollution. The oil may be a variety of materials, including crude oil, refined petroleum

products (such as gasoline ordiesel fuel) or by-products, ships' bunkers, oily refuse or oil mixed in waste.

Spills take months or even years to clean up (Etkin 1999). The oil penetrates and opens up the structure of
http://en.wikipedia.org/wiki/Liquidhttp://en.wikipedia.org/wiki/Petroleumhttp://en.wikipedia.org/wiki/Hydrocarbonhttp://en.wikipedia.org/wiki/Pollutionhttp://en.wikipedia.org/wiki/Crude_oilhttp://en.wikipedia.org/wiki/Gasolinehttp://en.wikipedia.org/wiki/Diesel_fuelhttp://en.wikipedia.org/wiki/Shiphttp://en.wikipedia.org/wiki/Wastehttp://en.wikipedia.org/wiki/Liquidhttp://en.wikipedia.org/wiki/Petroleumhttp://en.wikipedia.org/wiki/Hydrocarbonhttp://en.wikipedia.org/wiki/Pollutionhttp://en.wikipedia.org/wiki/Crude_oilhttp://en.wikipedia.org/wiki/Gasolinehttp://en.wikipedia.org/wiki/Diesel_fuelhttp://en.wikipedia.org/wiki/Shiphttp://en.wikipedia.org/wiki/Waste


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the plumage of birds, reducing its insulating ability, and so making the birds more vulnerable to

temperature fluctuations and much lessbuoyant in the water. It also impairs birds' flight abilities, making

it difficult or impossible to forage and escape from predators (Hogan C.M. 2008). Most birds affected by

an oil spill die unless there is human intervention (Dunnet et al. 1982). Marine mammals exposed to oil

spills are affected in similar ways as seabirds. Because oil floats on top of water, less light penetrates into

the water, limiting thephotosynthesis of marine plants and phytoplankton. This, as well as decreasing the

fauna populations, affects the food chain in the ecosystem (Teruhisa et al. 2003).

Oil spills are major environmental disasters of the present day petroleum industry that are cleaned up

using methods such as bioremediation, controlled burning, dredging and skimming ( Fingas et al. 2001).

Bioremediation is the use of living organisms, primarily microorganisms, to degrade the environmental

contaminants into less toxic forms (Vidali 2001). Not all contaminants, however, are easily treated by

bioremediation using microorganisms. For example, heavy metals such as cadmium and lead are not

readily absorbed or captured by organisms (Meagher 2000). Controlledburning can effectively reduce the

amount of oil in water, if done properly but can cause air pollution ( Fingas et al. 2001).Dredging is

used for oils dispersed with detergents but the dispersed oil droplets infiltrate into deeper water and can

lethally contaminate coral (Barry 2007).

As seen the methods in use today are not very efficient and leave behind significant

amounts of residues and cause environmental problems ( Fingas et al. 2001). Chitosan can be used

for the adsorption of oil from water. Chitosan is derived from sea food factory waste, prawn

shells. The cost of the commercially available chitosan is very high as a very high degree of

purity is maintained which makes the process expensive. Chitosan being a biodegradable

material would be an eco-friendly and effective alternative (Linden et al. 2000).

In India, it is estimated that more than one lakh tonne of prawn processing waste is being

wasted annually which could be gainfully utilised for manufacturing chitosan, a high value

industrial product( Santhosh et al. 2006). Other raw materials for chitosan production include
http://en.wikipedia.org/wiki/Plumagehttp://en.wikipedia.org/wiki/Buoyancyhttp://en.wikipedia.org/wiki/Marine_mammalhttp://en.wikipedia.org/wiki/Photosynthesishttp://en.wikipedia.org/wiki/Phytoplanktonhttp://en.wikipedia.org/wiki/Heavy_metalshttp://en.wikipedia.org/wiki/Cadmiumhttp://en.wikipedia.org/wiki/Leadhttp://en.wikipedia.org/wiki/Burninghttp://en.wikipedia.org/wiki/Air_pollutionhttp://en.wikipedia.org/wiki/Dredginghttp://en.wikipedia.org/wiki/Coralhttp://en.wikipedia.org/wiki/Plumagehttp://en.wikipedia.org/wiki/Buoyancyhttp://en.wikipedia.org/wiki/Marine_mammalhttp://en.wikipedia.org/wiki/Photosynthesishttp://en.wikipedia.org/wiki/Phytoplanktonhttp://en.wikipedia.org/wiki/Heavy_metalshttp://en.wikipedia.org/wiki/Cadmiumhttp://en.wikipedia.org/wiki/Leadhttp://en.wikipedia.org/wiki/Burninghttp://en.wikipedia.org/wiki/Air_pollutionhttp://en.wikipedia.org/wiki/Dredginghttp://en.wikipedia.org/wiki/Coral


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shrimp, crab shells and lobster shells of which are available to the tune of 30-50 tonne as waste

from the seafood industry. Even shell fish, krill, clams, oysters can be used for extraction.

In the present study, adsorbent (Chitosan) was prepared from the seafood industry waste,

prawn shells and studies are carried out for oil removal. Batch experiments are carried out for

kinetic studies of the removal of oil from oil-water solutions using chitosan. The effect of

varying parameters such as initial concentration and contact time has been studied.

2. Experimental Studies

2.1. Adsorbent preparation

Raw material is dried/wet shells of prawns were obtained from the seafood industry. The dried

shells were cleaned and broken in form of flakes. In deproteinisation (removal of all protein

adhered to the shells), 10g of the raw material was boiled with 250 mL of 3 % sodium hydroxide

for 30 min. It was then washed with distilled water to remove all traces of sodium hydroxide. In

demineralisation, the shell was treated with 250ml of 3% hydrochloric acid for two hours. It is

then washed with distilled water to remove all traces of hydrochloric acid. Chitin is obtained

from this step in the form of flakes. Deacetylation of chitin is required to produce chitosan. The

chitin obtained is then boiled with 40% sodium hydroxide for one hour. Chitosan was then dried

at a temperature less than 60oC. Testing for chitosan formation was done using a Ninhydrin test

in which 100 mg of chitosan was dissolved in 1% Acetic acid. A 2% Ninhydrin solution was

added. The solution was heated for about 20 min when bluish-purple colour was observed which

confirms the presence of chitosan. The yield of chitin and chitosan are 13.167% and 11.426% by

weight of dry shells, respectively.

2.2. Batch experiments


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The batch experiments were carried out in 100 mL beakers. Adsorption isotherm study was

carried out using solutions of 25ml each of different concentrations of oil and distilled water.

The effect of time was studied at 30oC using 0.05g of chitosan flakes in 25 mL of 10% (v/v) oil-

water solution. The samples were collected at different time intervals. The effect of initial

concentration in oil adsorption using chitosan was studied by varying the initial concentration of

oil in the solution from 2% (v/v) to 25% (v/v). The quantity of chitosan flakes was maintained

constant at 0.05g. The samples were kept aside for 6 min at 30oC. The flakes were picked up and

gravimetric analysis method was used to determine the amount of oil adsorbed.

3. Results and Discussion

3.1. Effect of contact time

Figure 1 shows the effect of contact time for the adsorption of oil on chitosan. It is evident that

there is a significant influence of time on the adsorption of oil on chitosan. It can be seen from

Figure 1 that the percent removal of oil from aqueous solution increases rapidly till 3 minutes

and reaches up to 33.616%. After that, the percentage removal of oil increases till 5 minutes and

reaches up to 41.28%. Further increasing the contact time has a negligible effect on the

percentage removal. Hence, the contact time for the adsorption of oil on chitosan for batch

studies has been taken as 6 minutes.


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0 2 4 6 8 10

15

20

25

30

35

40

45

OilRemoval(%)

Time (min)

Fig. 1. Effect of contact time on oil adsorption

3.2. Effect of initial concentration

In the present study, the initial concentration of oil in the solution was varied from 2% (v/v) to

25% (v/v) while keeping the amount of chitosan constant at 0.05g. Figure 2 shows the effect of

initial concentration on percentage removal of oil and adsorption capacity of chitosan. It can be

seen that oil adsorption is significantly influenced by initial concentration of oil in aqueous

solution. The percent removal decreases from 91.08% to 19.35% and adsorption capacity

increases from 6.74 g/g to 17.91 g/g while oil concentration increases from 2% (v/v) to 25%

(v/v) for the same contact time of 6 minutes and temperature of 30oC.


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0 20 40 60 80 100 120 140 160 180 20010

20

30

40

50

60

70

80

90

100

Oil Removal (%)

Adsorption Capacity (g/g)

Initail Concentation (g/l)

OilRemoval(%)

6

8

10

12

14

16

18

AdsorptionCapacity(g/g)

Fig. 2. Effect of initial concentration on oil adsorption

3.3. Adsorption isotherm

Batch adsorption experiments are carried out to estimate the maximum adsorption capacity of

chitosan adsorbent for the removal of oil from oil-water solution. The equilibrium studies are

useful to obtain the adsorption capacity of chitosan for oil. The obtained data from equilibrium

study can be represented in form of adsorption isotherm. If a quantity, q, of adsorbate is

adsorbed by a adsorbent at constant temperature and the steady state equilibrium concentration,

c, then the function q(c) describes the adsorption isotherm. Fig. 3 shows the adsorption isotherm

for oil removal using chitosan as an adsorbent. The maximum adsorption capacity of chitosan is

obtained as 17.91 g/g of adsorbent from the equilibrium experimental study. Chitosan shows the

better adsorption capacity for the oil removal as compared to other adsorbents.

The equilibrium data are tested with the Langmuir isotherm. This isotherm is applicable when

the extent of adsorbate coverage is limitedly to one molecular layer. The isotherm assumes a

dynamic equilibrium between the adsorbed phase and the liquid phase. Langmuir described


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chemisorption as the formation of an ionic or covalent bond between adsorbent and adsorbate.

The isotherm equation is given below in the form Eq. (1).

e

mme

e11

C

QbQq

C

+= (1)

Where, the parameterb is the Langmuir constant and qm is the quantity of adsorbate required to

form a single monolayer on unit mass of adsorbent. The qe and Ce are the amount adsorbed on

unit mass of the adsorbent (g/g) and equilibrium concentration (g/L) in fluid phase respectively.

A graph is plotted between (Ce/qe) and Ce which yields a straight line and shown in Figure 4. The

slope and intercept of this line then give the values of qm and b. The values ofqm and b are

calculated as 18.52 g/g and 0.195 L/g respectively. The value of coefficient of determination is

obtained as 0.999 which confirms the suitability of Langmuir isotherm to explain the equilibrium

data for the adsorption of oil using chitosan.

0 20 40 60 80 100 120 140 1600

2

4

6

8

10

12

14

16

18

AdsorbentCapacity(g/g)

Equilibrium Concentration (g/l)

Fig. 3. Adsorption isotherm for oil adsorption on chitosan


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0 20 40 60 80 100 120 140 160

0

2

4

6

8

10

Ce

/qe

Ce

Fig. 4. Langmuir isotherm for adsorption of oil on chitosan

4. Conclusion

Removal of oil from oil-water solution is carried out using chitosan prepared from seafood

industry waste, prawn shells. The kinetics study indicated that adsorption of oil on chitosan is

very fast with equilibrium being reached in 6 minutes. The percent removal decreases and

adsorption capacity increases while oil concentration increases. Equilibrium data are well fitted

with the Langmuir isotherm. The maximum adsorption capacity is obtained as 18.52 g/g with the

application of Langmuir isotherm. The biodegradability and effectiveness of chitosan make it a

good alternative for cleaning up oil spills.

References

Barry, Carolyn: Slick Death: Oil-spill treatment kills coral. Science News. 172, 67 (2007).
http://www.sciencenews.org/articles/20070804/fob1.asphttp://www.sciencenews.org/articles/20070804/fob1.asp


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Dunnet, G., Crisp, D., Conan, G., Bourne, W.: Oil Pollution and Seabird Populations [and Discussion],

Philosophical Transactions of the Royal Society of London. B 297(1087): 413427 (1982)

Emergency Response- Responding to Oil Spills. Office of Response and Restoration. National Oceanic

and Atmospheric Administration. (2007)

Etkin, S.D. Estimating cleanup costs for oil spills. International Oil Spill Conference. 168 (1999)

Fingas M.F., Charles, J.:The basics of oil spill cleanup. CRC Press, 2001.

Goosen, M. F.: Applications of Chitin and Chitosan, CRC Press. 132139 (1996)

Hogan C.M.: Magellanic Penguin. GlobalTwitcher.com, ed. N. Stromberg, (2008)

Linden, J., Stoner, R., Knutson, K. Gardner-Hughes, C.: Organic Disease Control Elicitors. Agro Food

Industry Hi-Te. 12-15, (2000)

Meagher, RB: Phytoremediation of toxic elemental and organic pollutants. Current Opinion in Plant

Biology 3 (2), 153162 (2000)

Sahu, Abhishek, et al. :Microwave mediated rapid synthesis of chitosan. 20(1), 171-175 (2009)

Santhosh, S., Mathew, P.T.: Preparation and Properties of Glucosamine Hydrochloride and

Carboxymethylchitin from Prawn Shell. In: National Seminar on Sustainability of Seafood

Production : Reflections, Alternatives and Environmental Control, Central Institute of Fisheries

Technology, India. Session 4, February 23 -24, 2006

Teruhisa, K., Masahiro, N., Hiroshi, K., Tomoko, Y.: Impacts of the Nakhodka heavy-oil spill on an

intertidal ecosystem: An approach to impact evaluation using geographical information system.

Marine Pollution Bulletin. 47( 1-6), 99-104 (2003)

Untold Seabird Mortality due to Marine Oil Pollution, Elements Online Environmental Magazine.

Vidali, M.: Bioremediation-An overview. Pure Appl. Chem. 73 (7), 11631172 (2001).
http://response.restoration.noaa.gov/topic_subtopic_entry.php?RECORD_KEY(entry_subtopic_topic)=entry_id,subtopic_id,topic_id&entry_id(entry_subtopic_topic)=184&subtopic_id(entry_subtopic_topic)=8&topic_id(entry_subtopic_topic)=1http://books.google.com/books?id=3YmDQyVfsDkC&dq=chitosan+seed+treatment&source=gbs_summary_s&cad=0http://globaltwitcher.auderis.se/artspec_information.asp?thingid=232http://www.yeacrops.com/Crop%20Protection%20Article.pdfhttp://www.yeacrops.com/Crop%20Protection%20Article.pdfhttp://www.springerlink.com/content/w55805p67601/?p=b6ff207b1de84999899e7a5762e10078&pi=0http://www.springerlink.com/content/w55805p67601/?p=b6ff207b1de84999899e7a5762e10078&pi=0http://www.sciencedirect.com/science/journal/0025326Xhttp://www.elements.nb.ca/theme/fuels/janet/russell.htmhttp://response.restoration.noaa.gov/topic_subtopic_entry.php?RECORD_KEY(entry_subtopic_topic)=entry_id,subtopic_id,topic_id&entry_id(entry_subtopic_topic)=184&subtopic_id(entry_subtopic_topic)=8&topic_id(entry_subtopic_topic)=1http://books.google.com/books?id=3YmDQyVfsDkC&dq=chitosan+seed+treatment&source=gbs_summary_s&cad=0http://globaltwitcher.auderis.se/artspec_information.asp?thingid=232http://www.yeacrops.com/Crop%20Protection%20Article.pdfhttp://www.yeacrops.com/Crop%20Protection%20Article.pdfhttp://www.springerlink.com/content/w55805p67601/?p=b6ff207b1de84999899e7a5762e10078&pi=0http://www.sciencedirect.com/science/journal/0025326Xhttp://www.elements.nb.ca/theme/fuels/janet/russell.htm

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Utilization of Chitosan Prepared From Seafood Industry Waste