Using conventional processes, biodiesel production is necessarily accompanied by the use of excess alcohol and production of a low value glycerol-rich co-product. There is currently a substantial worldwide surplus of this coproduct. While recovery of the alcohol is associated with high capital cost and energy requirement. This work tend to reduce the alcohol usage during biodiesel production and in situ convert the crude glycerol to an added valued product. The biodiesel was produced batch-wise at 130 – 160 oC with sulfuric acid as the catalyst. The effects of reaction temperature, catalyst concentration and molar ratio of triglyceride to methanol were studied. Approximately 100% conversion of the triglyceride was achieved. The glycerol conversion increased with increasing temperature and decreasing molar ratio. This represents proof-of-concept not only for reducing the excess methanol requirement, but also for combining production of fatty acid methyl esters with other added value products, whilst reducing glycerol production.
Keywords reactive coupling, polyglycerols, transesterification, etherification, biodiesel