文献类型：期刊文献

英文题名：Al-modified Pd@mSiO(2) core-shell catalysts for the selective hydrodeoxygenation of fatty acid esters: Influence of catalyst structure and Al atoms incorporation

作者：Cao, Xincheng[1,2,3,4] Zhao, Jiaping[1,2,3,4] Long, Feng[1,2,3,4] Zhang, Xiaolei[6] Xu, Junming[1,2,3,4,5] Jiang, Jianchun[1,2,3,4,5]

第一作者：Cao, Xincheng

通信作者：Xu, JM[1];Jiang, JC[1]

机构：[1]Chinese Acad Forestry, Inst Chem Ind Forest Prod, Nanjing 210042, Peoples R China;[2]Key & Open Lab Forest Chem Engn, Nanjing 210042, Jiangsu, Peoples R China;[3]Natl Engn Lab Biomass Chem Utilizat, Nanjing 210042, Peoples R China;[4]SFA, Key & Open Lab Forest Chem Engn, Nanjing 210042, Peoples R China;[5]Nanjing Forestry Univ, Coinnovat Ctr Efficient Proc & Utilizat Forest Re, Nanjing, Peoples R China;[6]Univ Strathclyde, Dept Chem & Proc Engn, Glasgow, Lanark, Scotland

年份：2022

卷号：305

外文期刊名：APPLIED CATALYSIS B-ENVIRONMENTAL

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000783004100003)】；

基金：Acknowledgements The authors would like to thank the financial support provided by the National Natural Science Foundation of China (2019YFB1504005 and 2019YFB1504000) .

语种：英文

外文关键词：Core-shell structure; Aluminum atoms incorporation; Selective hydrodeoxygenation; Diesel-range alkanes; Sintering resistant

摘要：The development of robust catalysts for selective hydrodeoxygenation (HDO) of fatty acid esters is key for production of the diesel-range alkanes under mild conditions. Here, we report a stable and efficient HDO catalyst (Pd@Al-x-mSiO(2)) that composed of inner uniformly dispersed metallic palladium core and the outer mesoporous silica shell doped with aluminum atoms. Using methyl palmitate as a model compound, Al-modified Pd@mSiO(2) catalyst (Pd@Al-3-mSiO(2)) exhibited higher catalytic performance (98% conversion rate and 99% selectivity towards diesel-range alkanes) as compared with the Pd@mSiO(2) and conventional Pd/gamma-Al2O3 catalysts (35% and 70% conversion rates, respectively) at 260 ? and 3.0 MPa H-2. Further, when using vegetable oils such as soybean and palm oils as raw materials, high yields of diesel-range alkanes (> 80 wt%) can be obtained under the mild conditions. The HDO reaction pathway was more dominant than the decarbonylation pathway when the reaction was catalyzed by Pd@Al-3-mSiO(2) catalyst, thereby reducing the loss of carbon atoms. Detailed characterization (Al-27 NMR, NH3-TPD, and in situ Py-FTIR) suggests that the incorporation of aluminum atoms brings not only Lewis acid sites, but also Bronsted acid sites via the formation of Si-OH-Al bonds. The synergy between the metallic Pd, Lewis-and Bronsted-acid sites is responsible for its high HDO activity under the mild conditions. Additionally, the core-shell structure enables fatty aldehyde intermediate preferentially adsorbed on the aluminum atoms in the outer silica shell and avoids direct contacting with metallic Pd, which inhibits the cleavage of C-C bonds to some extent. On the other hand, due to the protective effect of outer silica shell that inhibits the leaching and agglomeration of metallic Pd, the synthesized Pd@Al-3-mSiO(2) catalyst showed good stability with a slight loss (conversion decreased from 98% to 90%) over five cycles.