混合胺修饰的介孔硅胶吸附CO_2性能研究

Mixed-Amine Functionalized Mesoporous Silica Gel for CO_2 Capture

以介孔硅胶为载体,采用"嫁接+浸渍"两步法制备了混合胺(APTS+TEPA)修饰的介孔硅胶吸附剂。在固定床中考察了3-氨丙基三乙氧基硅烷(APTS)和四乙烯五胺(TEPA)负载量、吸附温度、进气流量对CO2吸附性能的影响,并研究了吸附剂的循环稳定性。结果表明,当APTS负载量30%,TEPA负载量30%(TEPA30-APTS30-MSG),吸附温度为70℃,进气流量为30 m L/min时,该吸附剂表现出最好的吸附性能,饱和吸附量高达3.04 mmol/g,较纯TEPA浸渍提高了37.6%。该吸附剂经10次吸脱附循环后,饱和吸附量仅下降2.96%,具有较好的循环稳定性。

A novel hybrid 3 - aminopropyltrimethoxysilane（ APTS） and tetraethylenepentamine （ TEPA ） modified mesoporous silica gel sorbent was synthesized by a two - step method,which combined grafting and impregnation methods. The effects of APTS and TEPA loadings,adsorption temperature and influent velocities on cO2 adsorption capacity were investigated in a self - assembled fixed bed reactor. It was found that the mesoporous silica gel modified with 30% APTS and 30% TEPA（TEPA30 - APTS30 - MSG）showed a maximum adsorption capacity of 3. 04 mmol - cO2 / g - sorbent at a optimal temperature of 70 ℃ and influent velocities of 30 mL/ min. The adsorption capacity is maintained after 10 cycles of adsorption - desorption process,indicating that the mixed - amine functionalized mesoporous silica gel exhibited an excellent stability in a prolonged cyclic operation.