1. University Malaysia Perlis, Faculty of Chemical Engineering Technology, Center of Excellent Geopolymer and Green Technology, Perlis, Malaysia
2. University Malaysia Perlis (UniMAP), Faculty of Mechanical Engineering Technology, Perlis, Malaysia
3. University Malaysia Perlis (UniMAP), Faculty of Chemical Engineering Technology, Perlis, Malaysia
4. Universitas Negeri Makasssar, Faculty of Mathematics and Natural Sciences, Indonesia
5. Gheorge Asachi Technical University of Lasi, Faculty of Materials Science and Engineering, Lasi, Romania