1. Department of Chemical Engineering, Universiti Teknologi PETRONAS, Seri Iskandar 32610, Malaysia
2. International Institute for Halal Research and Training (INHART), International Islamic University Malaysia, Kuala Lampur 53100, Malaysia
3. Center of Research in Ionic Liquids, Universiti Teknologi PETRONAS, Seri Iskandar 32610, Malaysia
4. Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744, Moto-oka, Fukuoka 819-0395, Japan