Chlorination roasting-coupled water leaching process for potash recovery from waste mica scrap using dry marble sludge powder and sodium chloride  

作　　者：Sandeep Kumar Jena Jogeshwar Sahu Geetikamayee Padhy Swagatika Mohanty Ajit Dash 

机构地区：[1]Mineral Processing and Central Characterization Department,Council of Scientific and Industrial Research(CSIR)-Institute of Minerals and Materials Technology(IMMT),Bhubaneswar,Odisha 751013,India

出　　处：《International Journal of Minerals,Metallurgy and Materials》2020年第9期1203-1215,共13页矿物冶金与材料学报（英文版）

摘　　要：The present paper reports the effective utilization of marble sludge powder(MSP)for the recovery of potash values from waste mica scrap using chlorination roasting-water leaching method.Characterization studies indicated the presence of dolomite as the major mineral phase in MSP,whereas muscovite and quartz were observed in the mica sample.The acid leaching studies suggest a maximum of 22%potash recovery under conditions:4 M H2SO4 acid,particle size of^100μm,stirring speed of 600 r/min,leaching temperature of 75℃,and leaching time of 90 min.The chlorination roasting-water leaching process was adopted to achieve the lowest level of 80%-90%potash recovery.The optimum conditions for the recovery of^93%potash from mica(~8.6wt%K2O)requires 900℃ roasting temperature,30 min roasting time,and 1:1:0.75 mass ratio of mica:MSP:NaCl.The roasting temperature and amount of NaCl are found to be the most important factors for the recovery process.The reaction mechanism suggests the formation of different mineral phases,including sylvite(KCl),wollastonite,kyanite,and enstatite,during roasting,which were confirmed by X-ray diffraction(XRD)analyses and scanning electron microscopy(SEM)morphologies.The MSP-blended NaCl additive is more effective for potash recovery compared with the other reported commercial roasting additives.

关 键 词：potash recovery mica scrap marble sludge powder chlorination roasting water leaching 

分 类 号：TQ443[化学工程—化学肥料工业] X705[环境科学与工程—环境工程]