ITS students generate bioethanol from palm waste

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Team of student from ITS Chemical Engineering Department. (photo: IO/ITS)

IO – Industrial waste without any further application may cause environmental damage – particularly solid waste from the palm flour industry. However, this effluent has been studied by a team of students from the Chemical Engineering Department of Sepuluh Nopember Institute of Technology (ITS) Surabaya, as it apparently contains bioethanol [fuel] substances.

The team consists of Anastasia Sandra Dewi, Richie Andyllo Stefanus and Maria Amelia Sandra, under the guidance of Prof. Dr Ir. Tri Widjaja MEng. They discovered that solid waste from palm contains lignocellulose (lignin, cellulose, and hemicellulose); these cellulose and hemicellulose water molecules can be hydrolysed or split into reducing sugars and then fermented into bioethanol.

However, lignin content is wrapped rigidity in cellulose and hemicellulose, so pre-treatment is required before fermentation. According to team leader Anastasia Sandra Dewi, the pre-treatment process is useful for dissolving lignin so that cellulose and hemicellulose substances can be maximally exploited. “In this process, we use a combination of acid pre-treatment (5 per cent sulfate acid -Red.) and organosolv (ethanol 51.29 per cent -Red.),” as explained by Sandra.

She continued, saying that after a pre-treatment phase, an enzyme hydrolysis stage, useful for hydrolyzing the cellulose and hemicellulose obtained from the pre-treatment process, enables reduction to sugars, glucose and xylose. “We use two enzymes, called cellulase and xylanase enzyme, and tween 80 surfactants to carry out this process,” added the Jakarta-based woman.

What’s more, Sandra says, after getting reducing sugars, the final stage is fermentation, through which the team uses Saccharomyces Cerevisiae fungus to convert reducing sugars into bioethanol. “This process is done in a shaker incubator for 72 hours at 35 degrees Celsius to get maximum results,” she said.

Sandra admitted the research work of the Student Creativity Program (PKM) required a total eight-day timespan, calculated without analysis, resulting on 0.42 per cent volume per volume (0.42 per cent v/v) of bioethanol from 50 grams of solid waste of palm. “It’s just on a laboratory scale; large scale experiments can yield several litres of bioethanol.”

Asked about future expectations, the 1997-born student said she hoped this research will be further developed and applied on a larger scale by industry. Also, solid waste from palms that has accumulated and becomes an environmental hazard can be accelerated for industrial use as bioethanol, an environmentally friendly alternative fuel. (ITS)