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Graphical abstract Highlights • Metals oxides doped Na 2 CO 3 fibers were prepared via ultrasonic atomization method. • Breakthrough (<1ppm) time of the Cu doped sorbent increased from 2 h to 6.5 h. • Cu doped sorbent showed high HCl selectivity with much low HCl/CO 2 ratio (1:25 v/v). • Cu doping strongly promotes the reactivity of Na 2 CO 3 fibers and HCl at 150 °C. • The sorbents could maintain stable cyclic performance after three regenerations. Abstract A novel inexpensive metal oxides doped sorbents had been investigated for selective capture of hydrogen chloride (HCl) from HCl/CO 2 (1:25 v/v) mixture gas at 150 °C. In this work, metals oxides (Fe, Mn, Ce and Cu) grains supported on the Na 2 CO 3 fibers were firstly prepared via ultrasonic atomization loading method, respectively. The results of HCl removal experiments showed that Cu dopant with optimal content synergistically facilitated HCl capture performance, continuously removing HCl from initial content of 1% to less than 1 ppm as long as 6.5 h. And the HCl capacity reached 3.15 mmol/g, corresponding to the conversion of active component Na 2 CO 3 was up to 0.89. Meanwhile, the Cu doped sorbent exhibited a strongly selective adsorption of HCl under extreme lower volume ratio HCl/CO 2 of 1:25. The enhancement of Na 2 CO 3 reactive activity depended on the highly dispersed copper oxides nanoparticles on the surface of Na 2 CO 3 fibers. CuO species in copper oxides reacted with HCl to form CuCl 2 , while the presence of amorphous phase connecting CuO nanoparticles and Na 2 CO 3 strongly promoted the mass transfer in product layers. The intensification of these two aspects made copper doped adsorbent exhibited significant HCl removal performance. Moreover, during regeneration test, the sorbents could maintain fairly stable cyclic performance within three cycles. [ABSTRACT FROM AUTHOR]

• 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]