Biodiesel From Waste Cooking Oil: Optimization of Production and Monitoring of Exhaust Emission Levels From its Combustion in a Diesel Engine

Abstract

Present study describes optimized production of waste cooking oil biodiesel (WCOB) using chemical and enzymatic transesterification. Maximum WCOB yield was 89% for chemical transesterification catalyzed by NaOCH3 and 95.9% for enzymatic transesterification using NOVOZYME-435. Optimized WCOB yield was procured for chemical transesterification when reactions were performed for 90 min at 45°C using 0.75% NaOCH3 and 6:1 methanol to oil molar ratio, whereas, enzymatic transesterification at 32.50°C for 60 h using 0.75% NOVOZYME-435 and 6:1 methanol : oil molar ratio. When compared the exhaust emission levels from diesel engine exhaust operated on conventional diesel fuel with the waste cooking oil biodiesel blends (WCOB), a notable reduction (%) in CO and PM levels was observed for WCOB5, WCOB20, WCOB40, WCOB50, WCOB80, and WCOB100 whereas in case of NOx emissions reduction (%) was observed only in case of WCOB5, WCOB20, and WCOB40, respectively.