1. UBF Maintenance Sdn Bhd, Kawasan Perindustrian Teluk Kalong Kemaman, Kijal, Terengganu, Malaysia
2. Department of Chemical Engineering, Faculty of Engineering, Osmaniye Korkut Ata University, Osmaniye, Turkey
3. Department of Chemical Engineering, Faculty of Engineering and Natural Sciences, Konya Technical University, Konya, Turkey
4. Environmental Engineering Program, Faculty of Engineering and Science, Curtin University Malaysia, Miri, Malaysia