| dc.description.abstract | Spent bleaching earth (SBE) is waste generated by the vegetable oil refining industries. SBE from the palm oil refining industries contains various contaminants, including free fatty acids, oil and trace metals. SBE generated is commonly disposed of in landfills, this conventional procedure is harmful to the environment. In this research project, spent bleaching earth (SBE) was successfully regenerated by first recovering the oil by solvent extraction using n-hexane as the solvent then digesting it in 3M NH4Cl solution and finally calcinating it at the optimum temperature for 3.5 hours followed the acid activation using 3M HCl. The SBE showed light color after calcination at 400oC. The extraction process was left to stand for different duration (1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 hours), the optimum yield (94.3%) was obtained at 6 hours. The calcination process was performed at different temperatures (100°C, 200°C, 300°C, 400°C and 500°C) and calcined for different length of time (1, 2, 2.5, 3, 3.5 and 4 hours) in order to find the optimum temperature and optimum heating time, the optimum temperature was found to be 400°C and the optimum heating/calcinating time was 3.5 hours with a bleaching efficiency of 78.5% before acid treatment. During acid treatment different cncentrations of the acid (0.1, 2 and 3M) were used to determine the right concentration, the optimum acid concentration of the acid was 3M with a bleaching efficiency of 97.9%. These results were compared to virgin bleaching earth (VBE) which had a bleaching efficiency of 98.6%. Treatment affected the clay structure and mostly removed the impregnated organic matter, the adsorbent capacity of regenerated SBE was comparable with VBE, showing the regenerated SBE has promising potential for many applications, in particular for the palm oil refining industry. Regenerated SBE gave significantly larger specific surface area, microporous surface area and total pore volume with smaller the average pore diameter. | en_US |
