STUDY OF MICROFILTRATION PERFORMANCE OF ALUMINA-KAOLIN CERAMIC MEMBRANE FOR REMOVAL OF GLYCEROL FROM BIODIESEL

Abstract

The production of biodiesel through the transesterification process produces several byproducts, mainly glycerol. Due to the negative effects of glycerol to the engine lifespan and efficiency, the free glycerol content in biodiesel was limited by the SNI and international standards below 0.02wt.% or 200 ppm, making the removal of glycerol one of the crucial process in biodiesel production. The conventional purification process requires high energy and generates high amounts of wastewater. Therefore the membrane separation technology becomes one of the prominent solutions, specifically the ceramic microfiltration membrane which has high thermal, chemical and mechanical strength. The development and application of a low-cost Alumina-Kaolin ceramic microfiltration membrane for water purification suggests potential in removing glycerol from biodiesel. The current study was done to evaluate the microfiltration performance of the Alumina-Kaolin ceramic membrane and to study the microstructure of the membrane affect to the separation performance. Several tests employed using different glycerol and water concentration in the feed of 1000 ppm, 5000 ppm and 10000 ppm. The evaluation gave high glycerol rejection rates of 92.07%, 98.52% and 98.94% for the respective feed concentrations with the permeate flux of 65.42 [l/(m2 h)], 61.09 [l/(m2h)] and 52.91 [l/(m2 h)] respectively. The microstructure characterization using the SEM images show that the pores of Alumina-Kaolin ceramic membrane with the pore size of 0.18 μm could separate the larger particles of glycerol-water droplets and gave high separation performance.