Effect of Acidification Mole Ratio and Solvent Volume Ratio of Glycerol Purification

Abstract

Glycerol is the side product in producing biodiesel. Biodiesel consists of 10% glycerol in average. Methanol, water, soap, salt, catalyst, and matter organic non glycerol (MONG) are found in glycerol as impurities. These impurities effects the concentration of glycerol significantly. Therefore, some treatments are needed to eliminate the impurities. This research is done to find out the effect of acidification mole ratio and solvent volume ratio to the process of purifying glycerol using phosphoric acid in acidification at pretreatment process. This research was started by adding acid to the glycerol to neutralize the alkaline catalyst which was used to break the soap formed become salt and free fatty acid which can be removed from the glycerol easily. Ethylene glycol was used in extraction with 1:0,5; 1:1 and 1:1,5 volume ratio (v/v) and 1:0,1; 1:0,3 and 1:0,5 acidification mole ratio. The MONG contained in the purified glycerol was analyzed with the standard of ISO 2098-1972. The results obtained was the more the volume of solvent used, the less the extraction time needed to gain glycerol with high purity. The highest purity obtained in this research was 92,0382% with 60 minutes of extraction time and 1:1 ratio solvent volume ratio (v/v).