Abdullah Synmsul, B. and Man, Z. and Ismail, L. and Maulud, A. and Abdul Mutalib, M.I. and Bustam, M.A. (2011) An Optimization Study on the Extraction of Benzothiophene from Model Fuel using the Ionic Liquids 1-Butyl-3-MethylimidazoliumOctylsulfate. Research Journal of Chemistry and Environment, 15 (2). pp. 510-518. ISSN 09720626