Students turn used oil into soap

06 June 2007 (TODAY)

SINGAPORE : What others throw away as waste, students Toh Yida and Varinder Singh see as opportunity.

After two years of research, the Temasek Polytechnic chemical engineering students have finally decoded the secret of turning used cooking oil into a simple and indispensable product: Soap.

The idea came to their lecturer U Tin Lin when he saw a hawker throwing used cooking oil away. "I thought we would find a better use for it," said Mr U.

When he asked the students if they were interested to develop the idea as a research project, Mr Toh, who has always been interested in protecting the environment, did not hesitate to say yes.

"It's not a new thing, making soap from oil," the third-year student said. "But it's usually made from fresh oil. Making it from used oil helps to reduce waste, because it would otherwise be thrown away."

The idea was also environmentally-friendly — just 250 grams of cooking oil is needed to make one kilogram of soap.

"It's very cost effective," said Mr Toh. "One litre of soap costs the school $1.80, while it takes less than 50 cents for us to make one litre. We can save the school an estimated $20,000 a year, and I really hope we can commercialise this."

Armed with an ample supply of used cooking oil from the school canteen vendors, the students cracked their heads on how to purify the dirty oil based on existing methods.

They came out with their own method after much tinkering around, before processing the purified material into soap.

Six months ago, they tested out the finished product by distributing it to the school canteen vendors to use for cleaning, but the work didn't stop there.

"They thought it was comparable to what they were using," said Mr Toh. "But they didn't like the smell, because initially it didn't smell very good."

The pair went back to the lab, and eventually produced an improved version with fruit scents like peach. After leaving the polytechnic, they plan to go on refining the product.

"We definitely want to improve the texture because at the moment it's a little harsh on the skin," said Mr Toh. "And if we can develop something for washing hands, why not?"

While there are plans to patent the process, the students and the school are taking it one step at a time. "We hope to be able to supply our school with soap first, and eventually, start supplying to other schools," said Mr U, who is from Myanmar. "To be able to do that, we will have to scale up what we have here, and I think that is possible eventually." - TODAY/na