Chlorination roasting-coupled water leaching process for potash recovery from waste mica scrap using dry marble sludge powder and sodium chloride
来源期刊：International Journal of Minerals Metallurgy and Materials2020年第9期
论文作者：Sandeep Kumar Jena Jogeshwar Sahu Geetikamayee Padhy Swagatika Mohanty Ajit Dash
文章页码：1203 - 1215
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 ～100 μm, 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（～8.6 wt% K2O） requires 900℃ roasting temperature, 30 min roasting time,and 1:1:0.75 mass ratio of mica : MSP : Na Cl. The roasting temperature and amount of Na Cl 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 Na Cl additive is more effective for potash recovery compared with the other reported commercial roasting additives.
Sandeep Kumar Jena，Jogeshwar Sahu，Geetikamayee Padhy，Swagatika Mohanty，Ajit Dash
Mineral Processing and Central Characterization Department,Council of Scientific and Industrial Research (CSIR)-Institute of Minerals and Materials Technology (IMMT)
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 ～100 μm, 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（～8.6 wt% K2O） requires 900℃ roasting temperature, 30 min roasting time,and 1:1:0.75 mass ratio of mica : MSP : Na Cl. The roasting temperature and amount of Na Cl 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 Na Cl additive is more effective for potash recovery compared with the other reported commercial roasting additives.
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