Degumming, Dewaxing and Deacidification of Rice Bran Oil‐Hexane Miscella Using Ceramic Membrane: Pilot Plant Study

Abstract

An indigenously developed low-cost clay-alumina-based ceramic microfiltration membrane of 19-channel configuration has been evaluated for degumming, dewaxing and deacidification of rice bran oil (RBO) miscella having different oil contents at pilot scale. Rice bran wax and soap particles in miscella will aggregate with changes in temperature. This suggests a technique for their effective separation. Low-temperature cross-flow membrane filtration was used for single-stage degumming-dewaxing and showed 70 % and 80 % removal of acetone insoluble residue from two RBO miscella samples, respectively. Color reduction was 50 %, and oryzanol retention was 70 %. NaOH was used for deacidification in a 10 % excess of that required based on the free fatty acid content in oil. This reduced free fatty acids to 0.2 %. Operating for 10 h with a 0.7 bar trans-membrane pressure, permeate fluxes of 15 and 8 L/m 2 hr were obtained for the degumming-dewaxing and deacidification operations, respectively. The process has advantages, such as high micronutrient content (1.56 % oryzanol) and negligible oil loss (2.6 %). Moreover, ceramic membrane processing of RBO miscella could be an effective pre-treatment step with respect to micronutrient enrichment, elimination of heating, neutral oil recovery and a viable option for solvent separation.

Low-cost ceramic membranes: A research opportunity for industrial application

“…The presence and quantity of these minority compounds depend on the nature and origin of the rice husk. Roy et al evaluated the pilot-scale efficacy of a lowcost alumina and clay-based membrane to remove polymers, waxes and acids from rice bran oil micelles [98].…”

Ultrafiltration-based degumming of crude rice bran oil using a polymer membrane

“…The conventional oil refinement process is characterized by high energy, water, and chemical product requirements, loss in neutral oil and nutrients, and a high rate of effluent production (Subramanian et al, 2001;Roy et al, 2014). In contrast, the use of membranes during processing has been shown to simplify the process.…”

Production of Rice Bran Oil with Light Color and High Oryzanol Content by Multi‐stage Molecular Distillation

“…This method can be used to achieve partial reduction in color while retaining higher amounts of oryzanol than in miscella refining. However, this method is more suitable as a potential technology to meet the stringent pretreatment requirements of physical refining [8,9]. Moreover, membrane refining needs to be developed on a larger scale and quantified through augmentation of pilotscale facilities [8].…”

“…However, this method is more suitable as a potential technology to meet the stringent pretreatment requirements of physical refining [8,9]. Moreover, membrane refining needs to be developed on a larger scale and quantified through augmentation of pilotscale facilities [8]. Therefore, it is particularly important to develop an efficient and industrially viable decoloration technology to improve the production of high-quality RBO with light color and high oryzanol retention.…”