Patent ID: 6143260
Filing Date: 2000-11-07
Classification: C01D,C01F,C22B,Y02P

Abstract:
A process for recovering lithium carbonate from a brine containing lithium and magnesium comprising:(a) preparing a feed brine by concentrating a brine comprising lithium and magnesium ions to saturate the brine with magnesium chloride and lithium chloride and to precipitate LiCl.MgCl.sub.2.7H.sub.2 O;(b) adding Ca(OH).sub.2 to the mother liquor recycled from step (e) to yield limed mother liquor;(c) mixing the limed mother liquor with said feed brine while maintaining a pH of from 8.40 to 8.80 to precipitate the magnesium ions as magnesium hydroxide and to precipitate calcium carbonate,(d) recovering the brine from step (c) and adding a sufficient amount of sodium carbonate to precipitate lithium carbonate;(e) separating the precipitated lithium carbonate from the mother liquor; and(f) recycling the mother liquor produced in step (e) to step (b).