Oil removal from spent bleaching earth of vegetable oil refinery plant using supercritical carbon dioxide

Siti Machmudah; Nabil Apta Maulana; Andhika Shafian Maindo Norman; Valencia Marchilia Nyoto; Irji Amrullah; Wahyudiono; Sugeng Winardi; I Gede Wenten; Motonobu Goto

doi:10.1016/j.heliyon.2022.e10826

Oil removal from spent bleaching earth of vegetable oil refinery plant using supercritical carbon dioxide

Heliyon. 2022 Oct 5;8(10):e10826. doi: 10.1016/j.heliyon.2022.e10826. eCollection 2022 Oct.

Authors

Siti Machmudah¹, Nabil Apta Maulana¹, Andhika Shafian Maindo Norman¹, Valencia Marchilia Nyoto², Irji Amrullah³, Wahyudiono⁴, Sugeng Winardi¹, I Gede Wenten⁵, Motonobu Goto⁶

Affiliations

¹ Department of Chemical Engineering, Institut Teknologi Sepuluh Nopember, Kampus ITS Sukolilo, Surabaya 60111, Indonesia.
² School of Chemical Engineering and Technology, Tianjin University, Beiyang Ave, Nankai District, Tianjin 300072, China.
³ Department of Biotechnology, IPB University, Jl Raya Dramaga, Bogor 16680, Indonesia.
⁴ New Industry Creation Hatchery Center, Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan.
⁵ Department of Chemical Engineering, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia.
⁶ Super Critical Technology Centre Co. Ltd., Kuwana, Mie 511-0838, Japan.

Abstract

The oil in the spent bleaching earth (SBE) matrix was successfully removed by applying the supercritical carbon dioxide (SCCO₂) extraction technique in a semi-continuous flow-type system. The SCCO₂ extraction process was conducted at 40-80 °C and 20-30 MPa with extraction time of ∼180 min. The color of SBE matrix changes from the dark to dark-pale color after the SCCO₂ extraction treatment exhibiting the substances including oil in the SBE matrix were successfully removed. The extracted oil yield was around 95% when the SCCO₂ extraction process was performed at 40 °C and 30 MPa with 10% ethanol addition as a co-solvent. The GC analysis showed that the prominent fatty acid constituents in the extracted oil are palmitic and oleic acids, furthermore it can be fed as a feedstock to produce biodiesel fuel. Next, it can be proposed that SCCO₂ extraction system is a viable way to extract oil from the SBE matrix.

Keywords: Extraction; Oil recovery; Spent bleaching earth; Supercritical CO2; Vegetable oil.