Adsorption isotherms of HFC-134a and VCM on activated carbon were obtained at various temperatures. Among the Langmuir, Freundlich and Langmuir-Freundlich models, the Langmuir-Freundlich model could well fit to isotherm obtained by experiment. Adsorption strength of VCM was stronger than that of HFC-134a on activated carbon.
Fixed bed adsorption and desorption experiments were performed with increasing flow rate and concentration. The breakthrough time of HFC-134a was smaller than that of VCM. The breakthrough curve of HFC-134a was shaped stiff, while that of VCM was S-shape. Mass transfer coefficients were estimated by matching constant-pattern-solution with experimental breakthrough data.
Mass transfer coefficients were estimated by matching constant-pattern-solution with experimental breakthrough data. Mass transfer coefficients were not significantly affected by the flow rate. Using the estimated mass transfer coefficient, breakthrough performance curves were well predicted. Adsorption breakthrough curve of HFC-134a seemed to be well fitted by the equilibrium model, while that of VCM by the nonequilibrium model.
