混合胺改性SBA-15的制备及其吸附脱硫特性

Adsorption of H_2S by Mixed-Amine Functionalized SBA-15

以γ-氨基丙基三乙氧基硅烷(APTS)为硅烷偶联剂嫁接到SBA-15载体表面,将甲基二乙醇胺(MDEA)浸渍到载体上,制备了混合胺改性H2S吸附剂,用于常温条件下净化气体中H2S。采用X射线衍射(XRD)、扫描电子显微镜(SEM)、N2吸附-脱附、傅里叶变换红外光谱(FT-IR)对吸附剂进行了表征。结果表明,采用嫁接反应混合物中氨基与硅原子的摩尔比为0.20、浸渍MDEA负载量占吸咐剂总质量50%的SBA-15(0.2/50)吸附剂,在温度30℃、原料气H2S体积分数227μL/L、流速100 mL/min条件下,穿透硫容和饱和硫容分别达到0.134和0.164mmol/g;原料气中含有的水分对吸附效果有促进作用。该吸附剂再生条件温和。吸附剂的有序介孔结构,以及表面嫁接和湿浸渍的结合有助于提高吸附剂的吸附容量和稳定性。

With the modification of SBA-15 by y-aminopropyltriethoxysilane （APTS） , and then the impregnation of methyldiethanolamine （MDEA） into the space of SBA-15 pores, a promising mixed-amine modified H2S adsorbent was prepared for the removal of H2S during the gas purification under normal temperature. The prepared adsorbents were characterized by X-ray powder diffraction （XRD） ,scanning electron microscope （SEM）,N2 adsorption-desorption and Fourier transform infrared spectroscopy（FT-IR） , and were tested for the removal of H2S from gas steam by the breakthrough adsorption-desorption experiments. The results showed that under the conditions of adsorption temperature 30°C , initial H2S volume fraction 227 jl ^ L/L in the feeding stream with 100 mL/min flow rate, SBA-15 （0. 2/50） demonstrated high H2S adsorption capacity with the breakthrough capacity of 0. 134 mmol/g and the saturation capacity of 0. 164 mmol/g. The moisture had a slightly positive effect on the removal of H2S. The regeneration of SBA-15（0. 2/50） was easily carried out at a mild temperature. The orderly mesoporous opening structure of adsorbent, and the combination of surface grafting and wet impregnation all were helpful for adsorbent to improve the cycling stability and adsorption performance.