PURIFICATION OF TRIALKYL ARSENIC

PURPOSE:To purify a trialkyl arsenic into such a high purity as to be useful in the electronic industry by reacting the trialkyl arsenic with a trialkyl aluminum, evaporation-removing fine metal impurities from the reaction product, adding an alkali metal halide and subsequently distilling the remained reaction product. CONSTITUTION:A tri (preferably 1-2C) alkyl arsenic containing 0.5-100ppm of volatile metal impurities such as silicon and zinc is subjected to react with a tri (preferably 1-4C) ethyl aluminum preferably in an amount of 1-2 times moles in an atmosphere of an inert gas such as argon with stirring. The reaction product is treated to evaporation-remove the fine metal impurities and further mixed with an aluminum halide such as preferably potassium fluoride to fix the trialkyl aluminum by complex formation therewith, followed by distillation- recovering the trialkyl arsenic preferably at 50-160 deg.C under atmospheric pressure, if necessary, under vacuum for the objective purification.