Patent ID: 6361750
Filing Date: 2002-03-26
Classification: C01B,F17C

Abstract:
A system for producing ultra-high purity BCl3 in condensed phase having less than 10 ppm phosgene from a low purity BCl3 condensed phase having phosgene impurity, the system comprising:a) means for injecting inert gas through a low purity BCl3 having phosgene impurity to produce a vapor stream comprising BCl3, inert gas, and phosgene; b) means for decomposing a major portion of the phosgene in the vapor stream comprising BCl3, inert gas, phosgene by heating to a first temperature to form a first intermediate vapor stream comprising BCl3, inert gas, carbon monoxide, chlorine, HCl and less than 10 ppm phosgene; c) a solid adsorbent means for adsorbing a major portion of the chlorine in the first intermediate vapor stream at a temperature lower than the first temperature, thereby producing a BCl3/inert gas vapor stream comprising less than about 10 ppm phosgene and some HCl; d) means for routing said BCl3/inert gas vapor stream comprising less than about 10 ppm phosgene and some HCl to a condenser; e) a first condenser means for condensing at least a portion of BCl3 in the BCl3/inert gas vapor stream to form a first condensed phase comprising BCl3, and HCl and inert gas and a second vapor stream comprising inert gas, BCl3, and light impurities; f) a second condenser means for condensing said second vapor stream, thus forming a gaseous stream comprising less than about 10 ppm BCl3 and a second condensed phase comprising BCl3 and HCl; and g) a stripper means wherein inert gas is used to strip molecules having specific gravity less than BCl3 from the first condensed phase to produce a third condensed phase comprising less than 50 ppm HCl, and stripped vapor phase.