Purification of materials in the gaseous phase by infrared laser radiation

It is proposed to prepare very pure materials by combining the selective dissociation of moleculues in the gaseous phase, under the action of high-power resonant infrared radiation transforming impurities into other chemical compounds, with the removal of these compounds by conventional purification methods. By way of example, an investigation was made of the dissociation of 1,2-dichloroethane and carbon tetrachloride in mixtures with arsenic trichloride. The measured dissociation rates were found to be independent of the impurity concentration and total pressure in the mixture. The composition of the final dissociation products was determined and it indicated that the method could be used to purify arsenic trichloride.