A comprehensive investigation of r32 adsorption kinetics onto MSC30 activated carbon powder

Abstract

The thermogravimetric method was employed to measure the adsorption kinetics of difluoromethane (R32) on MSC30 activated carbon powder adsorbent over a wide range of temperatures (25 °C to 150 °C) and pressures (up to 3000 kPa). The accuracy of various adsorption kinetics models, including FD model, LDF model, semi-infinite model, and modified adsorption kinetics models, were assessed to compare their suitability for predicting the kinetics uptake of the MSC30/R32 working pair. Based on the fitting of the Arrhenius equation, the activation energy Ea and pre-exponential coefficient DsRp2 were calculated to be 6262.37 (kJ·kg−1) and 0.00853 (s−1), respectively. The MSC30/R32 pair exhibited the highest diffusion time constant and adsorption rate among the common MSC30/refrigerant pairs. Furthermore, a new mass transfer coefficient model was proposed to enhance the accuracy and broaden the range of applicability of the existing model (Jribi model). Comprehensive validations were carried out using various adsorbent-adsorbate pairs over a wide temperature range. The Jribi model in conjunction with the proposed mass transfer coefficient model achieved high accuracy and precision in predicting the adsorption dynamics of diverse working pairs, both during the initial stage and near the saturation state. This study provides valuable insight into the adsorption kinetics analysis, which is essential in accurately simulating adsorption systems for various applications, including refrigeration and air conditioning.