Journal of Industrial and Engineering Chemistry, Vol.46, 244-257, February, 2017
Feasibility study of a novel copolyamide thin membrane assisted by melamine in terms of acid and thermal stability
A new acid stable copolyamide [PEI-Mel]-PA membrane was developed via interfacial polymerization assisted by melamine. The physico-chemical properties and separation ability were studied. It was compared with an acid stable polysulfonamide membrane in terms of acid stability. Melamine improved the thermal and acid stability and made the surface of the membrane more positively charged. The decreases in MgSO4 rejections were 56% and 31% for [PEI-Mel]-PA membrane after H2SO4 and HNO3 treatment, respectively. The stability of [PEI-Mel]-PA improved up to 16% and 48% in H2SO4 and HNO3, respectively in comparison with PEI-PA membrane. It recovered more than 97% of the acid.