BRIGHTENING NATURAL CALCITIC ORES TO YIELD CALCIUM CARBONATE

摘要

High gloss, fine CaCO3 particles are produced from a natural calcitic ore by (1) coarsely grinding the ore, (2) foam floating aq. suspension contg. 40, pref 30% of the coarse particle and separating colouration-producing impurities with the foam, (3) removing water from the residual prod. up to a solids content of =60, pref 65% and (4) wet grinding the prod. so that 80 wt.% of the resulting particles have a D.S.E particle size 2 mu. and a gloss value =94, pref. 95 on a G.E. seal. Prcess gives high gloss CaCO3 pigments in high solids content aq. suspension which can be pumped.