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Abstract: Hollow fiber renewal liquid membrane (HFRLM), a new liquid membrane technique inspired from surface renewal theory, is used to simultaneously remove and recover copper from acidic wastewater. The commercial extractant, LIX984N, is used as a carrier in liquid membrane phase, kerosene used as a diluent. CuSO4 solutions is used to simulate acidic industrial wastewater, in which the pH is adjusted by dilute H2SO4. The mass transfer mechanisms of the process are investigated. As a carrier-facilitated transport process, the addition of LIX984N in the liquid membrane phase can greatly improve the transport performance; the organic/aqueous stripping volume ratio from 1:10 to 1:7 on lumen side mixture is better in terms of the renewal effect and diffusion resistance. The higher pH in the feed phase (>3) and H2SO4 concentration in the stripping phase around 2.0molL−1 are favorable for the transport process due to the increase of mass transfer driving forces. The mass transfer fluxes increase with increasing flow rates on two sides. The countercurrent cascade experiments show that the HFRLM process could carry out the simultaneous removal and recovery of copper from wastewater successfully. The modeled results based on the surface renewal theory demonstrate a good agreement with experimental data. [Copyright &y& Elsevier]

• Optimum conditions for HCl selective removal over CuO x /Na 2 CO 3 sorbent were studied. • The diffusion coefficient in product layer was calculated according to RPM model. • According to the model, breakthrough time can be accurately predicted (error <4%). • 500t sorbents may be used to clean the blast furnace gas (400000 m3/h) up to 13 days. Selective removal of hydrogen chloride (HCl) using porous active sorbents has been considered to be a feasible way to reduce the harm of chlorine in flue gas. In this work, the kinetics process of HCl capture from CO 2 -rich mixture gases by CuO x /Na 2 CO 3 porous supported sorbent was studied systematically in a fixed-bed column at low temperature. The effects of flow rate, gas composition and operation temperature on HCl adsorption were intensively investigated. The results show that the HCl adsorption performance of sorbents decreased with the feed flow rate and CO 2 content increasing, whereas the effect of HCl concentration was negligible. In addition, HCl adsorption capacity increased with the increase of temperature (100–150 °C), but decreased after 170 °C. In the first part of dynamic heterogeneous reaction, axial dispersion mass transfer of reactive gas molecules dominated the overall reaction rate. But for second part, the gas diffusion in product layers replaced as a rate-controlled step. The overall sorbents conversion calculated by random pore model (RPM) demonstrated fine agreement with the experimental data and the diffusion activation energy was 23.11 kJ/mol. Moreover, the semi-empirical equation of BDST model was applied to predict the breakthrough curves with a standard deviation less than 4%. The forecasting results of industrial large-scale reactor indicate that 500 tons sorbents can effectively remove HCl from the flue gas (400000 m3/h) produced by 2650 m3 blast furnace for as long as 13 days. [ABSTRACT FROM AUTHOR]