PURIFICATION PROCESS AND APPARATUS FOR BORON TRICHLORIDE

摘要

PROBLEM TO BE SOLVED: To increase the production amount of a liquid BCl3 product having a phosgene content of <=10 ppm, a chlorine content of <=10 ppm and an HCl content of <=10 ppm. SOLUTION: An inert gas is blown into a raw material tank holding BCl3 containing phosgene as an impurity. The generated gaseous mixture of BCl3 and the inert gas is brought into contact with a catalyst at a high temperature to decompose the phosgene into carbon monoxide and chlorine. The flow of the mixed gas containing carbon monoxide and chlorine is cooled and brought into contact with an adsorbent to remove carbon monoxide and chlorine. The flow free from carbon monoxide and chlorine is cooled to form a condensed liquid. The liquid is stripped with an inert gas to obtain purified liquid BCl3. The inert gas is used also in the case of transporting the liquid product to a product tank.