CAJ | 학술논문

以具有骨架结构的SBA-15介孔分子筛为载体,采用浸渍法合成了具有高比表面积、不同金属氧化物含量的Cu-Zn-Zr介孔催化剂CZZx/SBA-15(x=0.3,0.4,0.5,0.6).采用N2吸附-脱附(BET)、 X射线衍射( XRD)、H2程序升温还原( H2-TPR)、CO2吸附( CO2-TPD)和透射电子显微镜( TEM)等手段对样品进行了表征.在固定床反应器上评价了其CO2加氢合成甲醇的催化性能.实验结果表明, CZZx/SBA-15催化剂具有介孔结构,负载的CuO, ZnO和ZrO2能够很好地分散在表面,并且负载氧化物晶粒尺寸不同.催化剂的铜比表面积SCu与甲醇催化活性呈近似线性关系,其中CZZ0.4/SBA-15催化剂表现出最大甲醇选择性(54.32%),与CZZ相比,甲醇选择性增加24.85%.随着金属氧化物负载量的增大,催化剂比表面积和SCu明显减小,甲醇选择性与收率也相应减小,负载型CZZx/SBA-15催化剂表面结构对CO2加氢合成甲醇反应活性起关键作用.
이구유골가결구적SBA-15개공분자사위재체,채용침지법합성료구유고비표면적、불동금속양화물함량적Cu-Zn-Zr개공최화제CZZx/SBA-15(x=0.3,0.4,0.5,0.6).채용N2흡부-탈부(BET)、 X사선연사( XRD)、H2정서승온환원( H2-TPR)、CO2흡부( CO2-TPD)화투사전자현미경( TEM)등수단대양품진행료표정.재고정상반응기상평개료기CO2가경합성갑순적최화성능.실험결과표명, CZZx/SBA-15최화제구유개공결구,부재적CuO, ZnO화ZrO2능구흔호지분산재표면,병차부재양화물정립척촌불동.최화제적동비표면적SCu여갑순최화활성정근사선성관계,기중CZZ0.4/SBA-15최화제표현출최대갑순선택성(54.32%),여CZZ상비,갑순선택성증가24.85%.수착금속양화물부재량적증대,최화제비표면적화SCu명현감소,갑순선택성여수솔야상응감소,부재형CZZx/SBA-15최화제표면결구대CO2가경합성갑순반응활성기관건작용.
A series of high surface areas and different mental oxide contents of Cu-Zn-Zr/SBA-15 mesoporous catalysts CZZx/SBA-15 ( x=0. 3, 0. 4, 0. 5, 0. 6 ) was directly synthesized by impregnation method. The catalysts were characterized by N2 adsorption-desorption ( BET ) , X-ray diffraction ( XRD ) , transmission electron microscopy(TEM), H2 temperature-programmed reduction(H2-TPR), CO2 temperature-programmed desorption( CO2-TPD) and N2 O titration technique( N2 O-RFC) . The catalytic activities of these catalysts were determined on the hydrogenation of CO2 to methanol in a fixed-bed reactor. The results showed that CZZx/SBA-15 catalysts possessed a highly ordered mesoporous structure, in which different grain size CuO, ZnO, ZrO2 species dispersed on the surface of SBA-15. A approximate linear relationship between the methanol synthesis activity and the total Cu0 surface area SCu was observed. CZZ0. 4/SBA-15 catalyst showed the largest methanol selectivity SCH3OH=54. 32%, which increased by 24. 85% as compared with CZZ catalyst. However, the methanol synthesis selectivity and yield decreased with the increasing of metal oxide content, which strongly suggested that the surface structure of the CZZx/SBA-15 catalysts played an important role in CO2 hydrogenation to methanol.