Mass transfer with chemical reaction—I. A second-order irreversible reaction

Abstract

The process of simultaneous absorption of two gases which react between themselves in an inert liquid is examined in the realistic limit of fast reaction. In this limit the nonlinear mass balance equations based on film theory are solved analytically using the method of matched asymptotic expansions. Explicit analytical expressions for the enhancement factors and concentration profiles of the gaseous solutes are derived. Results are given for the case where the two gases undergo an irreversible chemical reaction and the reaction rate is first order with respect to each of the solute concentrations. The nonlinear mass-transfer equations are also solved numerically using a shooting technique. When the dimensionless reaction rate constant is large, the analytical solution for the enhancement factor is found to be in excellent agreement with the numerical solution, with an error of less than 0.2% (better than any previously achieved).