Performance Study of Nonionic Filter Aid on Wet-Process Phosphoric Acid

Abstract

A non-ionic copolymer PAMA which has two functions of flocculation and surface activity was synthesized in aqueous solution. The copolymer was also characterized by means of infrared spectroscopic and unclear magnetic. The application performance of PAMA were studied, and the results show that the filtration rate of the phosphoric acid can be increased by about 3.8 times,the water content of the filter cake can be reduced by about 9.8%. Meanwhile, PAMA may increase the cake porosity by 25.82%,increase the mean void area about 7 times ,increase the surface contact angle of phophogypsum by 9.8°and decrease the surface tension by 7.4 mN·m-1 according to the SEM photos and hydrophobic experiment. All this confirms that PAMA is useful for vacuum filter system of wet process phosphoric acid.