MONOLITHIC REACTORS - MASS-TRANSFER MEASUREMENTS UNDER REACTING CONDITIONS

By 1993 90% of all cars sold in the USA and the European Community will be fitted with catalytic converters. After light-off has taken place the performance of these units is controlled by mass transfer to the catalyst surface. An accurate knowledge of mass transfer coefficients is thus essential for mathematical modelling and prediction of performance. Existing correlations for mass transfer coefficients exhibit an order of magnitude discrepancy between respective predictions. The following correlation for the Sherwood number in monolithic reactors has been developed from novel sets of experiments made under reacting conditions and is valid for 0.8 < (d/L Re Sc) < 130. This range is typical of conditions found in automobile exhaust gas cleaning applications. Sh = 0.766 (d/L Re Sc)0.483