Continuous hydrolysis of chloro-silane distn. residue with steam - at temp which increases during reaction to reduce dust formation

摘要

In working up residues (I) from chlorosilane distn. by hydrolysis with steam in the usual way, the novelty is that hydrolysis is carried out continuously, starting at a temp. of max. 160 deg.C and ending at a temp. of min. 170 deg.C. (I) is pref. passed through consecutive reaction zones at different temps., the first temp. at 130-140 deg.C and the other(s) at min. 200 deg.C. ADVANTAGE - The process is economical and little solid is carried over in the gas stream. In an example a laboratory paddle dryer with horizontal stirrer was charged continuously with 300 g/h (I) with powdery to lumpy consistency. This was reacted with 150 g/h steam. The mixer was operated at such a rate that the dwell of the solid in the mixer was 1 min. The zone at the (I) inlet was heated to 140 deg.C and that at the outlet to 220 deg.C. The amt. of dust collected on a dust filter was 5 g/h. If both zones were at 200 deg.C, the amt. of dust was 60 g/h