New Solvents Can Break Down Plant Cellulose To Produce Bioethanol

Sep, 2021 - By WMR

Researchers blended different combinations of zwitterionic molecules to generate a new solvent that is liquid below 100°C and very effective at breaking down cellulose.

Scientists from the Institute of Science and Engineering at Kanazawa University developed a fresh solvent compound to break down complex cellulose cell structures to produce bioethanol. Bioethanol with various combinations of zwitterionic molecules can generate a solvent at a temperature under 100 ° C and are very effective in breaking down cellulose.

These innovative solvents can perform in mild conditions, are environmentally friendly, and reduce toxicity compared to existing solvents. The process of making biofuels generally requires lowering cellulose in plants, which contain longer chains of polymer, into smaller sugar molecules. However, this work could lead to advanced technology for the conversion of unused biomass into fuel. Biofuels, such as ethanol, obtained by switchgrass and sugarcane will help reduce dependence on non-renewable fossil fuels. Cellulose has a complex network of hydrogen bonding, which enables it to withstand excessive chemical reactions. Current methods of cellulose processing depend on complex reaction conditions and toxic chemicals.

Now, scientists from the University of Kanazawa have used a special category of molecules called "zwitterions" to create novel solutions capable of eliminating cellulose. Zwitterions are special because they are both positive and negatively charged, however in different places in the molecule therefore they cannot be measured. These charges are very effective in disrupting hydrogen bonds that keep cellulose at bay. In these experiments, scientists combined four different zwitterions into different ratios. It was found that 22 compounds were aqueous at below 100 ° C. Two of the twenty-two compounds were very effective in eliminating cellulose. The work shows that it is possible to replace many of the toxic chemicals with environmentally friendly alternatives as the world moves forward in renewable energy systems and leads to less expensive, and safer production of ethanol from switchgrass.