Karmee, Sanjib Kumar2020-06-182020-06-182020Karmee, S.K. 2020. Technical valorisation of spent coffee grounds and food waste using sulphuric acid immobilised on silica. Biofuels, 11(2):155-161. [https://doi.org/10.1080/17597269.2017.1378989]1759-72691759-7277 (Online)http://hdl.handle.net/10394/34792https://www.tandfonline.com/doi/full/10.1080/17597269.2017.1378989https://doi.org/10.1080/17597269.2017.1378989Biodiesel from spent coffee grounds and food waste was prepared using sulphuric acid immobilised on silica gel (H2SO4–SiO2) as a catalyst. Reactions were carried out under reflux conditions using 15 mmol methanol. Food waste lipid and spent coffee oil gave 97% and 92% of biodiesel, respectively, after 24 h of reaction. After completion of the reaction, the immobilised acidic catalyst was separated by gravity filtration. Subsequently, the catalyst was reused for three consecutive cycles. At the end of three cycles, a 22% decrease in catalytic activity was observed for reactions involving spent coffee oil, whereas a 13% decrease in activity was observed during the use of food waste lipid as a starting materialenFood wasteSpent coffee groundsSulphuric acidImmobilisationBiodieselArticle