低品位滑石提纯工艺试验研究OA

The demand for low-grade talc is low in China,but high-grade talc is in short supply.In order to improve the utilization value of low-grade talc,high-grade talc was synthesized from low-grade talc and sodium silicate by com-bining chemical purification with hydrothermal synthesis.The acid dissolution of low-grade talc at different time was analyzed,and the best time of complete dissolution of gangue mineral(magnesite)was investigated.By examining the effects of factors such as pretreatment method,calcination,precursor formation condition,hydrothermal reaction tem-perature,time of low-grade talc on the crystallinity and purity of the synthesized product,the optimal purification process conditions were obtained:the magnesite in the low-grade talc was completely dissolved after acid treatment at 80℃for 2 h;At 60℃,the acid hydrolysis mixture was mixed with sodium silicate,and the pH of the system was adjusted to 7～8 for pre-reaction for 6 h to obtain the precursor,and the precursor reacted at 180℃under hydrother-mal conditions for 13 h,and finally prepared high-grade talc.The research results can provide reference for the high-value utilization of low-grade talc in China.