The Indian Institute of Technology (IIT) Mandi researchers have used hydrochar derived from orange peels as a catalyst to convert biomass-derived chemicals into biofuel precursors to overcome the socio-political instabilities associated with dwindling petroleum reserves.
The researchers heated dried orange peel powder with citric acid under pressure in a hydrothermal reactor (a lab-level "pressure cooker") for many hours. The hydrochar that was produced was then treated with other chemicals to introduce acidic sulfonic, phosphate, and nitrate functional groups to it.
The findings of the research team have been recently published in the journal ‘Green Chemistry'. The research was led by Dr Venkata Krishnan, Associate Professor, School of Basic Sciences, IIT Mandi, and co-authored by his students, Ms Tripti Chhabra and Ms Prachi Dwivedi.
Biomass derived products from naturally occurring materials – is currently the fourth most significant energy source that can meet the energy demand after coal, oil, and natural gas, in the country. Lignocellulosic biomass obtained from forestry and agricultural waste, for example, can potentially be converted to a variety of useful chemicals by various methods.
Of these methods, the use of catalysts for the conversion is particularly useful because such processes can be carried out with minimal energy input and the type of product obtained from the biomass can be controlled through the right choice of catalysts and reaction conditions.
Speaking about the research, Dr Venkata Krishnan said, "One of the driving interests among the renewable energy community is the development of relatively clean and energy efficient processes to convert biomass into useful chemicals, including fuel.
"We were able to synthesise the biofuel precursors under solventless and low temperature conditions, which decreases the overall cost of the process and also making it environment friendly, attractive from an industry point of view," he said.
"We used these three types of catalysts to bring about hydroxyalkylation alkylation (HAA) reactions between 2-methylfuran and furfural, compounds that are derived from lignocellulose, to produce fuel precursors," Ms Tripti Chhabra said.