Single phase blend: An advanced microwave process for improved quality low-cost biodiesel production from kitchen food waste

Accumulation and disposal of kitchen food waste is a substantial environmental issue due to the absence of appropriate reuse techniques. The present study developed a low-cost biodiesel production method and used Taguchi optimization technique to improve FAME yield. A single phase blend (oil, co-solvent and solvent mixture) was prepared and subjected to microwave irradiation to accelerate the initial slow reaction rate. Transesterification was carried out in a closed vessel under various temperature-pressure conditions. The reaction parameters were optimized through Taguchi model. Maximum FAME yield of 96.89 wt% was achieved at microwave cell pressure: 2.2 MPa, temperature: 170 degrees C, reaction time: 4 min and catalyst concentration: 0.5 wt% with single phase blend ratio 1:6:30 (oil: co-solvent: methanol). Methyl tert-butyl ether (MTBE) was used as co-solvent that contributed to maximum FAME conversion and produced glycerol tert-butyl ether (GTBE), a useful fuel additive as a byproduct. Improved cetane number observed for the kitchen food waste derived biodiesel signifies the fuel of superior fatty acid structure. Maximum 85 wt% GTBE conversion was attained at 200 degrees C temperature and cell pressure 3.9 MPa at 10 min reaction time. Microwave irradiation method consumed 2.7% lesser energy than conventional heating method. (C) 2018 Elsevier B.V. All rights reserved.