JOURNAL OF POROUS MATERIALS
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2024
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IF 2.5
Xue Changhao,Hou Xiaohui,Sun Weijie,Yuan Xia
The acidic molecular sieve carrier Hβ supported non-noble metal catalyst Ni/Hβ was prepared by equal volume impregnation method and applied to the hydroalkylation of benzene to cyclohexylbenzene. The effects of calcination procedures on the particle size of Ni and the dispersion degree of metal on the carrier were investigated. Compared with the samples reduced by hydrogen after calcination, the active site Ni of Ni/Hβ obtained by direct thermal reduction in hydrogen is mainly dispersed on the surface of the carrier, with better metal dispersion and smaller particle size of Ni. Under the optimized reaction conditions, the initial pressure of H 2 is 2.5 MPa, the amount of catalyst is 4% of the total reaction liquid, and at the reaction temperature 190 °C for 3 h, the conversion of benzene is 38.4%, the selectivity of cyclohexylbenzene is 72.8%, the selectivity of cyclohexane is 5.2%, the selectivity of dicyclohexylbenzene is 16.5%, and the selectivity of other by-products decreased to 5.5%. After the catalyst was reused for 5 times, the conversion of benzene and selectivity of cyclohexylbenzene were both have a slight decrease. Characterization results showed that the structure of the recovered catalyst was stable, but the specific surface area and pore volume decreased significantly, the resulted problem of catalyst pore blockage can be restored through calcination treatment.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
CATALYSIS LETTERS
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2021
·Vol. 152
·期 6
·1844-1853
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IF 3.186
Li Zihan,Yang Lingbin,Zhu Lijun,Xia Daohong
Novel B-doped NiP/Hβ (Hβ is the hydrogen proton exchanged β molecular sieve) catalysts were prepared and the catalytic performance for n-C 6 (n-hexane) isomerization was studied firstly. It was found that the mole ratio of Ni, P and B in preparing B-doped NiP had important influence on the crystalline structure and catalytic activity of NiPB. When the mole ratio of Ni, P and B was 1:1:1, the prepared NiPB was amorphous and NiPB/Hβ had the best catalytic activity with the conversion rate of n-C 6 , the yield and selectivity of isoparaffins being 79.93%, 78.34% and 98.01% respectively. It was also showed that the preparation conditions of catalyst including NiPB loading on carrier and calcination temperatures were the key factors for the catalytic performance of NiPB/Hβ. In controlled experiments, ammonia poisoned acid sites on the catalyst led to the markedly reducing of catalytic performance and metal sites were essentially for the dehydrogenation-hydrogenation reaction. The isomerization of n-C 6 catalyzed by NiPB/Hβ is a continuous alternating process of acid catalysis and metal catalysis, and the matching of acid sites and metal sites is of importance. Graphic Abstract
研究领域:
催化化学
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材料科学
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DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2022
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IF 5.876
Haoxi Jiang,Zhonghua Liu,Chuanxu Yao,Sheng Wang
The emission of volatile organic compounds (VOCs) causes serious atmospheric environmental problems and catalytic combustion is one of the most promising methods in the treatment of VOCs. In this work, the Pt/Hβ catalyst was fabricated via supercritical fluid deposition (SFD) for the first time and its activity was evaluated for toluene catalytic combustion. The preparation conditions during the SFD process were optimized. Na 2 PtCl 6 was selected as the precursor and 450 °C as the reduction temperature. The catalysts prepared by the SFD and impregnation (IM) were compared. The Pt/Hβ catalyst prepared by SFD had smaller size and higher dispersion and its T90 was 25 °C lower than that prepared by IM, which showed obvious size effect. For the similar activity, the Pt loading on catalyst prepared by SFD is only 50% of that on catalyst prepared by IM, showing obvious reduction effect for noble metal.
研究领域:
环境科学
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催化化学
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DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2022
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IF 4.889
Congcong Ji,Hongyu Wang,Shiqin Sun,Qi Li,Ji-Jun Zou,Shitao Yu,Huibing Shi,Genkuo Nie,Shiwei Liu
2-Ethylanthraquinone is frequently used for producing bulk consuming chemicals. However, the synthesis of 2-ethylanthraquinone is still restricted by expensive raw materials, complex preparation process and poor-cycling catalyst. Herein, a one-pot method is developed to synthesize 2-ethylanthraquinone using phthalic anhydride and ethylbenzene as feedstock by combination of acylation and dehydration over a Sc-modified Hβ catalyst. Sc-modified Hβ was prepared via impregnation and catalyzed conversion of phthalic anhydride about 58.8% and 2-ethylanthraquinone selectivity up to 78.5% which is better than the results by other metals-modified Hβ zeolites. By adjusting Sc loading amount in Hβ, more acids are created especially strong Lewis acid and an appropriate synergistic effect of Lewis/Bronsted acids is obtained for cascade reactions of acylation and dehydration. Then, the reaction conditions were investigated and the catalyst can be reused in 4 runs. This work provides a green and simple way for 2-ethylanthraquinone synthesis.
研究领域:
化学工程
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催化材料科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Yang Peng,Zhanwei Xu,Le Yu,Xucheng Li,Weiran Yang
The direct conversion of furfural (FUR) to 2-methyltetrahydrofuran (2-MTHF) was investigated over a trimetallic CuNiRe/Hβ catalyst. Under optimal reaction conditions at 240 °C under 3 MPa H 2 for 1 h, almost complete conversion of FUR and high-yield of 2-MTHF (81 %) was achieved. This is the highest yield reported for the direct conversion of FUR to 2-MTHF. HR-TEM demonstrated that the growth of Cu nanoparticles (NPs) on the surface of Hβ was inhibited after loading Ni or Re resulted in the smaller Cu particle size and better hydrogenation and hydrodeoxygenation activity. H 2 -TPR characterization exhibited that the reducibility of bimetallic and trimetallic catalysts was higher than that of monometallic catalysts·NH 3 -TPD explained that Hβ acid sites mainly contributed to FUR deoxygenation. The adsorption configurations of FUR, furfuryl alcohol (FOL) and 2-methylfuran (2-MF) on the catalyst were revealed by ATR-IR. Catalyst evaluation and control experiments proved that FUR was first hydrogenated to FOL, followed by hydrodeoxygenation to 2-MF, and finally hydrogenated to 2-MTHF catalyzed by the combination of three metals.
研究领域:
催化化学
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可再生化学
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能源化学
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产品关联
DOI
高影响因子
CATALYSIS COMMUNICATIONS
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2023
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IF 3.7
Jiuhu Zhao,Huiying Li,Yungang Wang,Rongshu Zhu,Senlin Sun,Jingwen Zhang,Chaolin Li,Mei Hong
Mesoporous In/Hβ-X series catalysts were prepared by desilication method with tetrapropylammonium hydroxide (TPAOH) and indium incorporation for selective catalytic reduction of NO with methane (CH 4 -SCR). The post desilication treatment conditions for preparing In/Hβ-X were optimized. Etching time is the most important desilication parameter influencing the resulting CH 4 -SCR performance of the catalyst. The In/Hβ-3 sample which was etched for 3 h presents the highest NO x conversion, 22% higher than In/H-Beta counterparts using commercial microporous beta. Obvious analysis reveals that besides generating mesopores, controlled desilication can modulate the proportion of InO + active sites and surface oxygen species, allowing more active sites to be exposed.
研究领域:
催化
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环境科学
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化学工程
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DOI
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
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2025
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IF 3.5
Yan Jiaqi,Chen Wenkai,Ni Wenjin,Li Lu,Fu Jinfeng,Yang Qian,Yang Zhiyong
N -cyclohexylcyclohexanimine (N-CCA), a by-product of cyclohexylamine (CHA) oxidation to cyclohexanone oxime (CHO), was used as the starting reactant for the efficient conversion to CHO under an oxygen atmosphere, utilizing the constructed surface hydroxyl-rich Ti-based catalysts. Of these, the 20% TiO 2 /Hβ catalyst exhibited unique catalytic activity and stability, achieving 45.9% N-CCA conversion and 82.1% CHO selectivity, with the content of high-boiling by-products not exceeding 1.0%. The superior catalytic performance, as evidenced by characterization results, stems primarily from: (i) the combination of TiO 2 and Hβ, which promotes the formation of a high specific surface area with fine TiO 2 nanoparticles and high-density Ti δ+ active sites, which facilitate the adsorption and activation of N-CCA; (ii) the construction of rich hydroxyl groups, which enhances the Brønsted acid sites, thereby improving the generation of active oxygen species; (iii) the intercrystalline embedding of TiO 2 and Hβ, which forms Ti–O–Si bonds, effectively inhibiting Ti leaching and ensuring excellent catalyst stability. The conversion of N-CCA, the main by-product of CHA oxidation, to the desired CHO using an efficient and robust 20% TiO 2 /Hβ catalyst represents an attractive pathway.
研究领域:
催化
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材料科学
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化学反应工程
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表面化学
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DOI
高影响因子
APPLIED SURFACE SCIENCE
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2017
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IF 3.387
Jinshe Chen,Zunbin Duan,Zhaoyang Song,Lijun Zhu,Yulu Zhou,Yuzhi Xiang,Daohong Xia
The amorphous NiP nanoparticles were synthesized and a novel amorphous NiP/Hβ catalyst was prepared successfully further. Due to the superior surface property of amorphous NiP/Hβ catalyst, it exhibited good catalytic application for n-hexane isomerization. The catalytic activity of amorphous NiP/Hβ catalyst was close to that of the prepared Pt/Hβ sample, and better than that of commercial catalyst and crystalline Ni 2 P/Hβ catalyst. What's more, the amorphous NiP/Hβ catalyst shows high resistance to different sulfur compounds and water on account of its unique surface property. The effect of loading amounts on surface property and catalytic performance was investigated, and the structure-function relationship among them was studied ulteriorly. The results demonstrate that loading amounts have effect on textural property and surface acid property, which further affect the catalytic performance. The 10 wt.% NiP/Hβ sample has appropriate pore structure and acid property with uniformly dispersed NiP nanoparticles on surface, which is helpful for providing suitable synergistic effect. The effects of reaction conditions on surface reactions and the mechanism for n-hexane isomerization were investigated further. Based on these results, the amorphous NiP/Hβ catalyst with superior surface property probably pavesa way to overcome the drawbacks of traditional noble metal catalyst, which shows good catalytic application prospects.
研究领域:
催化
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化学工程
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材料科学
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物理化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）