多级孔Fe-HBeta分子筛的合成及其催化性能探究  

Synthesis of the hierarchical Fe-substituted HBeta zeolite and its exploration on catalytic performance

作　　者：田韧 王诗瑶 连晨帅 吴旭[1] 安霞[1] 谢鲜梅[1] TIAN Ren;WANG Shi-yao;LIAN Chen-shuai;WU Xu;AN Xia;XIE Xian-mei(College of Chemistry and Chemical Engineering Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization,Taiyuan University of Technology,Taiyuan 030024,China;College of Food Science and Engineering,Shanxi Agricultural University,Jinzhong 030600,China)

机构地区：[1]太原理工大学化学化工学院气体能源高效清洁利用山西省重点实验室,山西太原030024 [2]山西农业大学食品科学与工程学院,山西晋中030600

出　　处：《燃料化学学报》2019年第12期1476-1485,共10页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(51541210);山西省自然科学基金(201701D121042)资助~~

摘　　要：采用软模板法一步合成了一系列铁同晶取代的多级孔Beta分子筛(nFe-HBeta,n=Fe/Al),并通过等体积浸渍法制备出系列Ni基催化剂(10Ni/nFe-HBeta)。结果表明,系列nFe-HBeta均为结晶度高、孔道结构丰富的片状结构。异质铁原子的引入在降低介孔相有序度的同时,促使沸石颗粒粒径下降,中强酸性位点数量显著减少。对于10Ni/nFe-HBeta催化剂而言,骨架铁与NiO之间存在协同作用,可增强活性组分Ni与载体间的作用力,提高活性金属Ni的分散度,降低NiO颗粒粒径。在乙醇水蒸气重整催化反应中,铁元素的引入可规避酸性位以抑制乙醇脱水反应,同时加强CO和CH4的水蒸气重整反应,有效提高H2选择性。其中,10Ni/0.15Fe-HBeta催化剂在500℃时,H2选择性高达72.15%,C2H5OH转化率为99.6%,反应12 h后的积炭量仅为4.3%。A series of hierarchical isomorphically Fe-substituted porous beta zeolites(BEAs) was synthesised in a one-step process via soft-template approach(nFe-HBeta, n = Fe/Al) and a series of Ni-based catalysts(10 Ni/nFe-HBeta) was prepared by equal volume impregnation. The results showed that the nFe-HBeta zeolites possessed a sheet-like structure with a high crystallinity and numerous porous channels. The introduction of the heterogeneous iron atoms could reduce the degree of order of the mesoporous phase and decrease the size of the zeolite particles and the number of moderate and strong acidic sites. For the 10 Ni/nFe-HBeta catalyst, a synergistic effect existed between the framework iron and NiO species, which could enhance the interaction between the active Ni and HBeta support, increase the dispersion of the active metal Ni, and reduce the NiO particle size. In the ethanol steam reforming(ESR) reaction, Fe introduction could inhibit the ethanol dehydration reaction through the shielding of acidic sites and could promote the steam reforming reaction of CO and CH4, effectively improving the H2 selectivity. Among the Fe-containing catalysts, 10 Ni/0.15 Fe-HBeta showed a H2 selectivity of up to 72.15% and an ethanol conversion rate of 99.6% at 500 ℃, while the amount of coke deposition was only 4.3% after a 12 h reaction.

关 键 词：Fe同晶取代 HBeta分子筛 NI基催化剂 乙醇水蒸气重整 

分 类 号：O643[理学—物理化学]