A Study of Residual Oils Recovered from Spent Bleaching Earth: Their Characteristics and Applications

Abstract

This study described the extraction of residual oils of spent bleaching earth (SBE) from palm oil refining industry, the properties and applications of residual oils obtained there from. Residual oils of SBE (acid-activated, WAC and neutral, NC) were recovered via solvent and supercritical-fluid (SC-CO 2 ) extraction. The yields of residual oils recovered from WAC were higher than those from NC using solvent and SC-CO 2 extraction respectively. Both the residual oils recovered from WAC and NC had fatty acids composition (FAC) similar to that of crude palm oil. These oils exhibited poor qualities in terms of free fatty acids (FFA) content and peroxide value (PV). As the residual oils had very high FFA value (more than 10%), they were no longer suitable for food applications. Alternatively, these oils can be converted to their respective methyl esters for biofuel and other non-food applications as they were thermally and chemically stable with induction period of up to 29 h in Rancimat test. The methyl esters conversion via esterification and transesterification gave optimum yields of more than 80%. The methyl esters obtained have comparable fuel properties as petroleum diesel; hence, they can be used as diesel substitute.

Castor Oil: Properties, Uses, and Optimization of Processing Parameters in Commercial Production

“…The unprocessed clays when activated by concentrated acid followed by washing and drying acquire more adsorptive power to adsorb color pigments from the oil. 88…”

Dry Heating of Palm Fruits: Effect on Selected Parameters

“…Free Fatty Acid (FFA) content of the oil was determined by using the PORIM Test Method (Loh et al, 2006). Sodium hydroxide solution of 0.02 M was prepared and standardized with potassium hydrogen phthalate.…”

“…Deterioration of Bleachability Index (DOBI) was determined by using the PORIM test method (Loh et al, 2006). The method developed by (Swoboda, 1982), defines DOBI as the ratio of the spectrophotometric absorbance at 446 nm to that at 269 nm.…”

The Effect of Spent Bleaching Earth Filler-Based NPK Fertilization on Proline, Growth and Yield of Maize

“…One of the uses of fertilizer through NPK fertilization is the most important factor in maize cultivation where a source of additional NPK fertilizer is needed to meet the nutritional needs of the maize plant. According to Kheang et al (2010), the residue of CPO oil in the SBE was 20-30% and has a similar clay shape.…”