Intermediate Biodiesel Purification by Refined Glycerin Wash

Biodiesel has attracts worldwide attention due to its potential of replacing fossilbased
fuel. In order to conform the stringent international standard, downstream
purification is an essential section in the overall process. The feasibility of crude
glycerin as biodiesel purifier was investigated. Crude biodiesel was washed with
refined glycerin under conditions that have been close to commercial operating
practice possible. The correlation of the extraction variables; temperature, glycerin
concentration and weight ratio of glycerin to biodiesel were investigated. Three basic
parameters were investigated; glycerin concentration, extraction temperature and
ratio of glycerin to biodiesel. Experiments were performed in order to determine the
optimum condition of the glycerin-wash using Taguchi method. The pretreated
biodiesel was further purified with water. Characterization on the biodiesel was done
to ensure the standard requirement was fulfilled. The result show that glycerin wash
can significantly remove the soap content. The integrated glycerin wash (60%
glycerin purity, 85°C and 15wt% ratio of glycerin to biodiesel) followed by 15wt%
water wash is proved to be a better method for biodiesel purification.