HKUST-1 and its graphene oxide composites: Finding an efficient adsorbent for SO2 capture

To develop effective SO 2 adsorbents, HKUST-1 and HKUST-1 @ GO were synthesized by hydrothermal and room-temperature methods, and characterized by SEM, BET, XRD , TG and FTIR. The preparation method of the adsorbent, amount of adsorbent, initial concentration of SO 2 , and the influence of time and temperature on the adsorption of SO 2 by HKUST-1 and HKUST-1@GO were studied. The results showed that the hydrothermally synthesized HKUST-1@1.2%GO was the best adsorbent for SO 2 , the SO 2 concentration did not affect the final adsorption efficiency, the best adsorption time was 20 min, and the best adsorbent dose was 200 mg. The kinetics and isotherms of HKUST-1@1.2%GO were studied, and the thermodynamic parameters were calculated. The static SO 2 adsorption of HKUST-1@1.2%GO conformed to the pseudo-first-order model and Freundlich model, and was a spontaneous exothermic process. Lowering the temperature is beneficial to the adsorption. At 288 K, the maximum theoretical SO 2 adsorption capacity of HKUST-1 @1.2% GO was 72.49 mmol g −1 . After five adsorption cycles, the adsorption efficiency only decreased by 0.8%, indicating that the adsorbent has excellent repeatability and cyclic stability.