Preparation of manganese dioxide loaded activated carbon adsorbents and their desulfurization performance

Abstract

Manganese dioxide loaded activated carbon adsorbents (MnO₂/AC) were prepared and characterized by N₂ adsorption-desorption, BET method, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectrometry (FT-IR) and scanning electron microscopy (SEM). Effects of preparation conditions and adsorption conditions on desulfurization performance of the adsorbents were studied in a fixed-bed adsorption apparatus. Experimental results show that the surface area and pore volume of MnO₂/AC decreased compared with the unmodified activated carbon, but the adsorption capacity to H₂S was improved greatly. A suitable H₂S removal activity was obtained with manganese dioxide to activated carbon ratio of 1.1: 1 and the calcination temperature of 250°C. At the adsorption temperature of 40°C and gas flow rate of 20 mL/min, the H₂S saturation capacity and H₂S removal rate reached up to 713.25 mg/g and 89.9%, respectively.