宁夏大学学报（自然科学版中英文）2026，Vol.47Issue(5)：393-405,13.DOI:10.20176/j.cnki.nxdz.20260901
Ni落位对正庚烷加氢异构-氢解竞争的调控作用
Effect of Ni Placement on the Competition between n-Heptane Hydroisomerization and Hydrogenolysis
摘要
Abstract
Using n-heptane(n-C7)as a model molecule,two types of Ni-based bifunctional catalysts,namely Ni-HZSM-22/Al2O3 and Ni-Al2O3/HZSM-22,featuring atomic-and nanoscale metal-acid proximity,respec-tively,were prepared to systematically investigate the effect of Ni placement on the competition between hydroi-somerization and hydrogenolysis.The results show that Ni placement simultaneously regulates the Ni‒support interaction,the surface chemical environment of Ni species,and the distribution of accessible Ni sites.Com-pared with those of Ni-HZSM-22/Al2O3,the Ni2+-related Ni 2p3/2 peaks of Ni-Al2O3/HZSM-22 shift markedly toward higher binding energies,indicating strong Ni-O-Al interactions between Ni and Al2O3.Meanwhile,the Al2O3-supported environment favors the maintenance of a relatively high proportion of accessible Ni sites at moderate-to-high Ni loadings.The n-C7 hydroisomerization results show that the i-C7 yields over both series of Ni-based bi-functional catalyst exhibits a volcano-type variation.At low Ni loadings,the reaction is limited by insufficient dehydrogenation/hydrogenation functionality of the Ni sites,whereas at high Ni loadings,enhanced Ni-mediated hydrogenolysis decreases the isomerization selectivity.Among the catalysts,2.0Ni-Al2O3/HZSM-22 achieves the highest isomer yield of 57.19％.Moreover,the trend in isobutance(i-C4)formation over this catalyst is similar to that over the Pt reference catalyst,while its CH4 yield is relatively low.These findings indi-cate that the Al2O3-supported Ni sites can effectively supress Ni-mediated C-C bond hydrogenolysis while main-taining the required dehydrogenation-hydrogenation functionality.The key to designing Ni-based bifunctional hydroisomerization catalysts is therefore to achieve an appropriate balance between the metal and acid functions while suppressing the hydrogenolysis activity of the Ni sites,rather than simply optimizing metal-acid proximity or metal loading.关键词
正庚烷加氢异构/Ni基双功能催化剂/金属-酸亲近关系/Ni落位方式/氢解活性Key words
n-heptane hydroisomerization/Ni-based bifunctional catalyst/metal-acid proximity/Ni place-ment/hydrogenolysis分类
化学化工引用本文复制引用
史佳伟,张丛超,钱羽童,齐若冰,陈斯诺,杜云飞,曹徐旸,穆超,王胜平..Ni落位对正庚烷加氢异构-氢解竞争的调控作用[J].宁夏大学学报（自然科学版中英文）,2026,47(5):393-405,13.基金项目
国家自然科学基金资助项目(22678306) （22678306）
宁夏回族自治区科技创新团队建设项目(2025CXTD020) （2025CXTD020）
宁夏自然科学基金创新群体项目(2024AAC01002) （2024AAC01002）
