Study on 0.2 ?m Al_2O_3 ceramic membrane fouling in clarification of Tangkeqing Compound water extract / 中成药

ABSTRACT

AIM: To discuss the fouling mechanism in 0.2 ?m Al_2O_3 commie membrane microfiltation of Tangkeqmg Compound water extract. METHODS: The total filtration resistance and its distribution were used as indexes to study the effect of pore size and materials of ceramic membrane on membrane fouling in clarification. SEM (scanning electronic microgragh) technology was used to study the microstructure of surface and section of new membrane and contammted membrane and physica and chemical examination were done on the fouling substances on the membrane surface. RESULTS: The pore size and materials of membrane affected the total filtration resistance and its distribution in clarification. The results of filtration resistance dislribution and SEM suggested that the fouling of 0.2 ?m Al_2O_3 membrane mainly lied on the surface. The contaminations on membrane surface were mostly the substances holding function groups, such as C=O, CO-NH and C-O-C. According to volume percentage, the semidiameter of contaminations on the membrane was mostly around 23.738 ?m. However, according to quantity percentage, the semidiameter of contaminations on the membrane was mostly around 0.521 ?m. CONCLUSION: Study on the fouling mechanism of the membrane is of great significance for looking for the effective measures for relieving the downward trend of the membrane flux and for the appropriate membrane cleaning in the clarification of Tangkeqing Compound extract using 0.2 ?m Al_2O_3 ceramic membrane.