Snail (Helix pomatia) Shells as a Catalyst for Biodiesel Synthesis

Biodiesel is an alternative to conventional diesel. The use of heterogeneous catalysts in biodiesel production is promising, as it is easier to separate it from the product than homogeneous ones. It was determined that the calcined grape snail ( Helix pomatia ) shells show good catalytic efficiency in rapeseed oil transesterification process with methanol. It was determined that the CaO concentration in calcined grape snail ( Helix pomatia ) shells was 97.74 ± 0.12%. Using the response surface methodology, the biodiesel production process was optimised. The influence of interaction of independent variables and optimal conditions for the synthesis of rapeseed oil methyl ester were determined: an alcohol to oil molar ratio of 10.6:1, a catalyst concentration of 5.7 wt % and a reaction duration of 7.8 h at a temperature of 64°C. The physical and chemical properties of produced biodiesel at optimal process conditions are presented, their compliance with the requirements of biodiesel standard EN 14214 are discussed. The produced biodiesel using snail shells which are food processing waste meets the requirements of the EN 14214 standard and can be used in diesel engines during the summer period.