| dc.description.abstract | Glycerol compound is a byproduct the making of biodiesel that high economic value. Glycerol with various levels of quality are needed as raw materials in industry. Glycerol used in the food industry, cosmetics industry, pharmaceutical industry, tobacco processing industry, industrial lubricating, and also oleochemical industry. In the future when the demand of biodiesel is increasing along with population growth, it also increases the production of glycerol. The use of glycerol especially pure glycerol in a various of products have been developed. But before the process of making a compound glycerol derivatives of glycerol refining process takes most of which crude glycerol was mixed with other materials. The purpose of this research is to determine the effect of adsorbent concentration on the purification of glycerol in order to determine the type and combination of effective adsorbent to produce pure glycerol. The treatment tested in this study is the type of adsorbent (activated carbon and bentonite) and a combination of both adsorbent added. The ratio of activated carbon and bentonite added is 4: 4 (adsorbent total is 8 %), 4: 6 (adsorbent total is 10%), 4: 8 (adsorbent total is 12%) and 4: 10 (adsorbent total is 14%) of the weight of crude glycerol. The results showed that the concentration of adsorbent used in the bleaching have significant effect on water content, ash content and color of glycerol produced but did not have real impact on the number of acid. The use of adsorbent with a total of 14 % to produce glycerol with water content and ash content lower than most others. Based on absorbance values, the adsorbent total 14 % are also more effective in absorbing the colors then the color of the resulting glycerol is clearer. The influence of the total of adsorbent to the water content is higher the amount of adsorbent is added, then the value of water content lower glycerol. Neither the value of ash content nor the lower absorbance with increasing number of adsorbent used. The ratio of the use of adsorbent (activated carbon: bentonite) is the best ratio of 4:10 with the lowest water content value (0.663%), the lowest ash content (0.0543%), transmitance (low absorbance value of 1.987) and 8.74 glycerol levels %. Glycerol analysis using GC-MS (Gass Chromatography Mass Spectrometry) showed that glycerol before and after the purification process still contains the methyl esters of glycerol so that low purity. This is because the reaction is not perfect at the time of the process of making biodiesel. But after the purification process of glycerol content increased from 0.85% to 8.74%. | en |
