Bleaching of montan wax - by rapid mixing with chromic acid and distn. of water

摘要

Bleaching of montan wax (opt. mixed with other waxes) is carried out by (a) rapidly adding the molten wax to a chromic acid soln. contg. 60-140 g/l CrO3, 400-600 g/l total H2SO4 and 300-500 g/l free H2SO4 at elevated temp., and (b) agitating the mixt. and simultaneously distilling off H2O in an amt. such that the free H2SO4 content remains >=200 g/l. Compared with prior art processes, the process can be completed in a shorter time with less wax degradation and thus lower chromic acid consumption, using smaller reactors without equipment for vapour recycle or H2O addn.