PURIFICATION OF HYDROGEN CHLORIDE CONTAINING ORGANIC MATERIAL

摘要

PROBLEM TO BE SOLVED: To improve the quality of hydrogen chloride to a level usable for the washing of semiconductor materials by adsorbing and removing organic materials from crude hydrogen chloride containing organic materials using a synthetic resin adsorbent. SOLUTION: The impurities to be removed from hydrogen chloride are organic materials, especially aryl alcohols and their derivatives. The impurity level of the hydrogen chloride after the purification treatment is preferably <=10 ng/mL, especially <=0.1 ng/mL in terms of the content of aryl alcohols and their derivatives in a 35% aqueous solution of hydrogen chloride for the use requiring extreme quality such as semiconductor use. The synthetic resin adsorbent for the purification treatment is preferably a styrene-divinylbenzene resin. The use of a resin containing >=0.5 mL/g of pore having a pore diameter of 30-100Åis more effective. The specific surface area of the synthetic resin adsorbent is preferably >=600 m2/g.