PENINGKATAN KADAR GLISEROL HASIL SAMPING PEMBUATAN BIODIESEL DENGAN METODE ADSORPSI ASAM LEMAK BEBAS (ALB) MENGGUNAKAN FLY ASH

Crude glycerol is a byproduct of the production of biodiesel produced about 10% (w/w) of the weight of biodiesel . Crude glycerol still contains many impurities that cause low levels of glycerol into that utilization is not maximized . Purified glycerol widely used in several fields such as manufacture of drugs and cosmetic. Therefore, there needs to be a process of purification in order to obtain higher levels of glycerol . This study aims to perform the purification of crude glycerol to determine the method of adsorption and adsorption capacity of fly ash. Adsorption processes associated with the equilibrium adsorption performed at constant temperature (isotherms) to obtain the maximum adsorption capacity data. Langmuir and Freundlich models proposed to interpret the data of adsorption equilibrium of free fatty acids in the glycerol . This research was carried out by varying the mass of adsorbent 2.5g , 5.0g , 7.5g and 10g, and the adsorption time 40, 50, 60, 70 and 80 minutes. Purification of crude glycerol were analyzed using analysis of free fatty acids and glycerol analysis. The results showed that 10g Mass adsorbent and adsorption time of 60 minutes can reduce Free Fatty Acid (FFA) that glycerol levels increased . The maximum adsorption capacity of 5.186 x10- 4 mmol/g. Based on the value of the correlation coefficient (R2) indicates that the Langmuir and Freundlich models are suitable for this study.