eprintid: 2259 rev_number: 2 eprint_status: archive userid: 1 dir: disk0/00/00/22/59 datestamp: 2023-11-09 15:50:28 lastmod: 2023-11-09 15:50:28 status_changed: 2023-11-09 15:42:21 type: article metadata_visibility: show creators_name: Elsheikh, Y.A. creators_name: Man, Z. creators_name: Bustam, M.A. creators_name: Yusup, S. creators_name: Wilfred, C.D. title: Brønsted imidazolium ionic liquids: Synthesis and comparison of their catalytic activities as pre-catalyst for biodiesel production through two stage process ispublished: pub keywords: BMIMHSO4; Crude palm oil; GC; IL; KOH, Biodiesel; Catalysis; Catalyst activity; Electrochemical sensors; Esters; Fatty acids; Gas chromatography; Potassium hydroxide; Standards; Sulfur compounds; Synthetic fuels; Transesterification; Vegetable oils, Ionic liquids note: cited By 99 abstract: In the present work, study was undertaken to prepare biodiesel via a two-step transesterification process. The high free fatty acids (FFA) value contained in the crude palm oil (CPO), which cause several problems with the straight alkaline-catalyzed, were converted to fatty acid methyl esters (FAME) before introducing KOH-catalyzed transesterification step. In order to evaluate their catalytic activities, three Brønsted acidic imidazoliums were investigated. These ionic liquids (ILs) appeared to be promising candidates to replace conventional acidic catalyst for biodiesel production due to their unique properties. Among them, a longer side chains 1-butyl-3-methyl-imidazolium hydrogensulfate (BMIMHSO4) was found to be more superior to the other two catalysts. Based on the experimental results, a catalyst (BIMHSO 4) concentration of 4.5 wt., methanol/CPO molar ratio of 12:1, a temperature of 160 °C, and agitation speed of 600 rpm provided a final CPO acid value lower than 1.0 mg KOH/CPO within 120 min. The second alkali-catalyze step was performed at agitation speed of 600 rpm, 60 °C, 1.0 KOH for 50 min. The final biodiesel product in 98.4 yield was analyzed by gas chromatography (GC). The determined physicochemical important properties of POME were confirmed with American Standards for Testing Material (ASTM). © 2010 Elsevier Ltd. All rights reserved. date: 2011 official_url: https://www.scopus.com/inward/record.uri?eid=2-s2.0-78649332786&doi=10.1016%2fj.enconman.2010.08.005&partnerID=40&md5=be6648175cfdb23b4e57225e72993343 id_number: 10.1016/j.enconman.2010.08.005 full_text_status: none publication: Energy Conversion and Management volume: 52 number: 2 pagerange: 804-809 refereed: TRUE issn: 01968904 citation: Elsheikh, Y.A. and Man, Z. and Bustam, M.A. and Yusup, S. and Wilfred, C.D. (2011) Brønsted imidazolium ionic liquids: Synthesis and comparison of their catalytic activities as pre-catalyst for biodiesel production through two stage process. Energy Conversion and Management, 52 (2). pp. 804-809. ISSN 01968904