| Hydrogen sulfide（H2S） has unpleasant smell and is toxic. Natural gas, refinery gas, coal gas and biogas contain acid gases such as H2 S that must be removed from the gas stream due to the toxicity of H2 S can be lethal to human beings, also to prevent corrosion to piping and production facility caused by the acid gases. In order to meet the regulation requirement, which the international environmental regulations for gas emission by the industries have become stringent with respect to the release of gas containing sulfur, various purification technologies have been used. In this study, we chose ordered mesoporous material SBA-15 as absorbent supporters, with using two methods of surface grafting and wet impregnation in combination, a mixed-amine modified adsorbent for H2 S adsorptionhad been prepared. The contents of the work are listed as follows:（1） After modification using γ-aminopropyltriethoxysilane（APTS） onto the surface of SBA-15, then methyldiethanolamine（MDEA） was impregnated into the space of pores, a promising mixed-amine modified H2 S adsorbent had been prepared, in order to realize the removal of H2 S for gas purification under normal temperature. The adsorbents were characterized by X-ray powder diffraction（XRD）, scanning electron microscope（SEM）, N2 adsorption/desorption and Fourier transform infrared（FTIR） spectroscopy. The adsorbents were tested for the removal of H2 S from gas steam by carrying out breakthrough adsorption/desorption experiments. The results from these tests showed that under the conditions of adsorption temperature in 30 ℃, initial concentration of H2 S in the feeding stream maintained 227 μL/L and a flow rate of 100 mL/min, SBA-15（0.2/50） demonstrated high H2 S adsorption capacity（breakthrough capacity 0.134 mmol/g-sorb and saturation capacity 0.164 mmol/g-sorb）. The moisture had a slightly positive effect on the removal of H2 S and SBA-15（0.2/50） was regenerated easily at a mild temperature. In addition, the orderly mesoporous opening structure of adsorbent generated synchronous effect in the adsorption process, the combination of surface grafting and wet impregnation was helpful to improve the cycling stability and adsorption performance.（2） A promising mixed-amine modified H2 S adsorbent had been prepared by modification using γ-aminopropyltriethoxysilane（APTS） onto the surface of SBA-15 and impergnanting tetraethylenepentamine（TEPA） into the space of pores, in order to realize the removal of H2 S for gas purification under normal temperature. The adsorbents were characterized by X-ray powder diffraction（XRD）, scanning electron microscope（SEM）, N2 adsorption/desorption and Fourier transform infrared（FTIR） spectroscopy. The adsorbents were tested by carrying out breakthrough adsorption/desorption experiments for the removal of H2 S from gas steam. The results showed that under the conditions of adsorption temperature in 30 ℃, initial concentration of H2 S in the feeding stream maintained 227 μL/L and a flow rate of 100 mL/min, NH2-SBA-15（TEPA/40） demonstrated high H2 S adsorption capacity（breakthrough capacity 0.108 mmol/g-sorb and saturation capacity 0.134 mmol/g-sorb） and can be stably regenerated at a mild temperature. In addition, the adsorption performance depended on allowing sufficient contact time between the H2 S molecules and adsorbents to reach equilibrium, so the gas flow rate should be appropriate.（3） The experimental breakthrough curves of H2 S adsorption behavior were investigated by using the deactivation model and the deactivation model was found to give good agreement with the experimental results. The deactivation model was appropriate to analyze and quite successful in predicting the breakthrough curves of H2 S adsorption when the experimental conditions were settled. |
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