Monday, April 30, 2007

Biodiesel production from mixture of used cooking oil and canola oil

Ajay K. Dalai, Titipong Issariyakul, Lekha C. Meher, Mangesh K. Kulkarni, and Narendra N. Bakhshi. Department of Chemical Engineering, University of Saskatchewan, 57 Campus Drive, Saskatoon, SK S7N 5A9, Canada

There are several attempts made to produce biodiesel from various fresh vegetable oils and used cooking oils. However, the combination of these two sources as feedstock for biodiesel production is relatively unexplored. The purpose of this study was to optimize canola oil (CO) to used cooking oil (UCO) ratio to produce high yield and quality biodiesel while maintaining a simple and low cost transesterification process using an alkaline catalyst. This study could provide an alternative means to make use of UCO for a low-cost biodiesel production process.

 Methyl and ethyl esters were produced from mixtures of CO and UCO at various ratios by KOH-catalyzed transesterification. The mixture of UCO and CO at ratio of 80:20 to 20:80 was used as feedstock in the present study. The transesterification was carried out in a batch-type reactor with 6:1 alcohol (methanol or ethanol) to oil molar ratio using 1% KOH as a catalyst and stirring speed of 600 rpm and 50 oC. As expected, transesterified products derived from lower UCO to CO ratios showed higher ester percentage. The quality of esters can be improved by using more CO in the feedstock. The characteristics of various esters including density, viscosity, acid value, water content, heating value, freezing point, boiling point distribution, and fatty acid compositions will be presented at the conference.