Absorption of phosphine in aqueous solutions of sodium hypochlorite and sulphuric acid

Abstract

The kinetics of absorption of phosphine in aqueous solutions of sodium hypochlorite and sulphuric acid was studied in a stirred cell and a stirred contactor. The reaction of phosphine with aqueous solutions of sodium hypochlorite was found to first order with respect to phosphine and hypochlorite. The effect of pH on the second order rate constant was also investigated. The value of the second order rate constant was found to vary from 230 to 77,000 1./g mole sec at 28°C in the pH range of 12.95-9.40. The reaction of phosphene with aqueous solutions of sulphuric acid, in the range of concentrations of 80 to 92% by weight, was also found to be first order with respect to phosphine. The value of the pseudo first order rate constant was found to be in the range of 3 × 10⁶ ∂4 × 10' sec^-1 at 28°C. Copper sulphate was found to be an effective catalyst in sulphuric acid solutions.