The New Paper 16 Jun 10;
THERE might just be a new way of cleaning up oil spills in future - with the help of a substance called chitosan.
Chitosan comes from chitin, which is derived from the pulverised shells of crustaceans. It is used in the food processing, health-care and pharmaceutical industries.
A group of students and their lecturer from Temasek Polytechnic's School of Applied Science have come up with a project exploring the use of chitosan and styrofoam to deal with oil spills.
The project won third prize in the recently concluded Singapore Junior Water Prize competition. The finals were held last month.
The annual competition aims to encourage students to take an interest in water research. Organised since 2008 by Ngee Ann Polytechnic, it is supported by the Lien Foundation and PUB, the national water agency .
The project members- final-year chemical engineering students Johnson Seow, 20, Lim Shao Xuan, 19, Ng Bokai, 19, and their lecturer,Mr Dion Khoo, 38 - say the method is effective, though local companies do not use it at present.
The team took two years to complete their project.
The idea came after the students and Mr Khoo read a journal article on the positive aspects of using chitosan.
Johnson said: "The article said chitosan could absorb fat well. So we thought, why not see if it works well with oil?"
The team spent six months researching and finding materials.
Chitosan-coated balls
The next year was spent coating pinky nail-size styrofoam balls with chitosan and ensuring that they could soak up oil while staying afloat.
The team said each ball could soak up the oil completely in fewer than three seconds in still water conditions. The last six months saw the team building a two-tiered prototype for submission.
The prototype shows oil-soaked, chitosan-coated styrofoam balls are placed in the first tier, a desorption unit with turbulent water.
Within 24 hours, the oil separates from the balls and can be drained into the second-tier recovery unit, which has a spray to flush down the oil.
The no longer oil-soaked balls are left in the desorption unit and can be re-used as they are still coated with chitosan.
From the recovery unit, the oil and water are drained out via separate valves.
Shao Xuan explained: "The oil can now be re-used, and will not go to waste."
One current oil spill clean-up method sees oil being burned off the water's surface, which is harmful to the environment.The oil also cannot be used again. The project cost the team less than $700 - about $500 for the prototype with tubing and fittings, and about $160 for 80g of chitosan. The oil and the styrofoam balls were from the polytechnic laboratory.
Mrs Grace Quah,who chairs the competition organising committee, said the team was awarded third prize as they ventured into a relatively new area of research and made good use of materials available to them in their laboratories.
"The judges felt that the project was creative, and the students were very passionate about their work," she added.
Mrs Quah was not aware if chitosan was currently used by local companies to clean upoil spills.
Operations manager Ho Yew Weng from Oil Spill Response said his company has "no experience (using) chitosan".
Oil Spill Response was employed by the Maritime and Port Authority of Singapore (MPA) during the recent oil spill off the Singapore coast and it had used dispersants.
Associate Professor Zhang Yong from the National University of Singapore's Division of Bioengineering said the use of chitosan in cleaning up oil spills has been "well-researched". He considers it a feasible option when dealing with oil spills here in the future.
In response to The New Paper's queries, a PUB spokesman said that the organisation will meet with MPA to explore the option "should the use of chitosan be found effective in cleaning up oil spills".
The team is keen to develop their project further. "We believe in our work and would like to further refine it," said Johnson.
Teams from NUS High School and Dunman High School were tied for the top prize. They will form a joint team to represent Singapore at the Stockholm Junior Water Prize competition in Swedenin September.
