CATALYSIS COMMUNICATIONS
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2023
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IF 3.7
Shuang Luo,Jingwei Li,Jiansu Ran,Ruixue Yangcheng,Yuntong Cui,Yuxin Zhang,Jianjian Wang
A novel catalyst prepared by a facile ‘one-pot’ solvothermal method was developed for the efficient production of lower polyols from glucose solution. Under the optimal reaction conditions, the yield of diols was up to 50.7%, outperforming the recent works reported in the literature (<48%). Deeper investigation results revealed that the modification of MgO y on Pt-WO x could tune the surface acid-base properties, thereby promoting the yield of lower polyols. Combining the experimental and characterization results, a possible reaction mechanism during the conversion of glucose to lower polyols over Pt-WO x -MgO y was proposed.
研究领域:
化学工程
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催化科学
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DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
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2024
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IF 5.6
Yaohong Zhou,Wenqi Wang,Yujing Jin,Peng Wang,Suqin Wu,Changxi Deng,Wanming Xiong,Xiaohua Zhang
Developing high-performance acid-base catalysis over perovskite for alcohol aerobic oxidation has received increasing attention, but the fundamental understanding of its surface acid-base property and performance relationship remains largely unknown. Accordingly, a series of LaFeO 3 perovskites were fabricated via modified Pechini approach with the addition of different chelating agents to modulate their respective acid-base amount and oxygen vacancy concentration, which subsequently were employed in the aerobic oxidation of vanillyl alcohol (a lignin model), to generate vanillin for elucidating the relationships between the catalytic activity of LaFeO 3 perovskite and its acid-base property as well as oxygen vacancy. The results demonstrated that existence of non-linear relationships between the vanillin yield and the acid-base amount as well as oxygen vacancy concentration of LaFeO 3 catalyst. Moreover, neither acid-base sites nor oxygen vacancies were the solely factors affecting the activity of LaFeO 3 perovskite towards vanillyl alcohol oxidation for vanillin production. Mechanism studies proclaimed that the reactive oxygen species derived from the adsorption of molecule oxygen on oxygen vacancies generated by anion defects combing with Lewis acid sites (Fe 3+ /Fe 2+ ) to yield FeO x active pairs, which jointly dominated the pathway for vanillyl alcohol oxidation to produce vanillin. Overall, this work offers guidance for designing effective perovskite-based catalysts for lignin conversion to produce value-added chemicals by selectively modulating its acid-base property and oxygen vacancy.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
FUEL
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2024
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IF 6.7
Faraz Ahmad,Yueli Wen,Muhammad Zeeshan,Bin Wang,Awais Ashraf,Bai Hui,Zheng Cui,Chengda Li,Samia Kausar,Wei Huang
The balance of acid-base property is crucial for the catalytic performance of Side-Chain Alkylation of Toluene with Methanol (SATM). In this work, Na 3 PO 4 modified NaX catalysts with suitable middle base strength and feasible acid-base center distance were prepared by direct solvent-evaporation and exhibited the best styrene selectivity of 45.4 % and the total yield of side chain alkylation products of 71.7 %, respectively at methanol conversion up to 99.9 % in NaX-P (0.075) . Notably, the selectivity exhibits surprising stability in the evaluated 15 days, which might owe to the uniform dispersion of active species and constant acid base property. Combined the comprehensive characterizations of solid-state NMR, FTIR, SEM, and XPS, etc., with Density Functional Theory (DFT) calculation results, it is revealed that O-1264 are affected mostly by loading Na + or both of Na + and PO 4 3- , which exhibits the least adsorption energy and the highest electronic cloud density in the four kinds of oxygen atoms according to the calculated Bader charge. Therefore, the structure S4 (O-1264) was considered to be the most stable and meet the basicity requirements for SATM.
研究领域:
催化化学
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材料科学
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理论化学
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产品关联
DOI
高影响因子
Catalysis Science & Technology
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2018
·Vol. 8
·期 13
·3346-3356
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IF 5.365
Peidong Li,Qiao Han,Xiaomin Zhang,Yangyang Yuan,Yanfei Zhang,Hongchen Guo,Li Xu,Lei Xu
Side-chain alkylation of toluene with methanol is a potential technology to realize the one-step production of styrene under mild conditions. Herein, a series of cesium X zeolites with different cesium contents were prepared through an ion-exchange method. The performance of the CsX zeolites was extensively investigated in the side-chain alkylation of toluene and methanol. The acid–base properties of the involved CsX were characterized and the results showed that the acid–base properties present regular changes with varied cesium contents. Based on the full understanding of the acid–base properties of the involved CsX, the reaction behaviors of the main and side reactions in the side-chain alkylation of toluene with methanol over CsX were investigated and new insights were revealed. It has been found that the crucial steps for the main reactions were the activation of toluene and the formation of formaldehyde from dehydrogenation of methanol when the cesium exchange degree of CsX was lower and higher than 32.3%, respectively. The hydride transfer reaction between styrene and carbon deposition is responsible for the formation of ethylbenzene over CsX with lower cesium contents, while the transfer hydrogenation of styrene with methanol and formaldehyde was the main path for ethylbenzene formation over CsX with higher cesium contents. And it was found that the existence of Brønsted acid sites accounts for the formation of xylene over CsX. These new findings will give a new insight into the reaction behaviors of the side-chain alkylation of toluene with methanol over CsX and may also provide a potential modification method for high-efficiency catalysts.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2022
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IF 24.319
Bowen Yuan,Jian Zhang,Zhe An,Yanru Zhu,Xin Shu,Hongyan Song,Xu Xiang,Wanning Wang,Yusheng Jing,Lirong Zheng,Jing He
Transformation of ethanol to more valuable C 4+ alcohols by coupling reaction has been of great interest from the point of view of chemistry and technology of biomass utilization. This work reports atomic Ru on Mg and Al containing layered double oxides (MgAl-LDO) for ethanol coupling to C 4+ alcohols. The atomic Ru remarkably promotes the coupling of ethanol, achieving a selectivity of 82.6% to C 4+ alcohols under an ethanol conversion of 29.6%. Through tailoring Ru dispersion and acid-base properties, it has been found that atomic Ru promotes ethanol dehydrogenation and the following aldol condensation of acetaldehyde.
研究领域:
化学
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催化技术
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生物质利用
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产品关联
DOI
高影响因子
CATALYSIS COMMUNICATIONS
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2020
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IF 3.612
Baining Lin,Fan Xu,Yingjie Hu,Xuhong Du,Yingping Zou,Huasheng Xie,Kang Wang,Yonghua Zhou
Developing multifunctional catalyst for cascade reactions such as one-pot synthesis of methyl isobutyl ketone (MIBK) from acetone and hydrogen is critical for practical applications. Here, we adjusted the acid-base property by doping phosphor into h-BN and used it as support for Pd. Experiments and characterizations indicated that the phosphor-doped h-BN could catalyze the aldol condensation and dehydration by modulating the ratio of BNH 2 , N 2 P=O and N 3 P-OH groups thereon. An acetone conversion of 58.24% and MIBK selectivity of 68.39% were achieved over Pd/BN( H )P-E-0.07, providing a new avenue for metal-free materials utilized in the cascade reactions.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
BIOMASS & BIOENERGY
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2018
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IF 3.358
Jiaxiong Liu,Yajin Li,Huimin Liu,Dehua He
Ce 1-x Zr x O 2 (0 ≤ x ≤ 0.2) solid solutions were prepared by hydrothermal method and applied for the synthesis of glycerol carbonate from glycerol and CO 2 in the presence of 2-cyanopyridine (dehydrant) with dimethyl formamide (DMF) as a solvent. The physicochemical properties of the catalysts were characterized by ICP, XRD , BET, H 2 -TPR, CO 2 /NH 3 -TPD, TEM and XPS . The activation route of CO 2 and glycerol were measured by DRIFTS and FT-IR. Compared to pure CeO 2 , Ce 1-x Zr x O 2 solid solutions exhibited enhanced activity in the present reaction system, and the improved catalytic activity was associated with the BET surface area and the acid-base properties. DRIFTS results showed that the chelating bidentate carbonate species was the main adsorption pattern for CeO 2 and no striking differences between Ce 0·98 Zr 0·02 O 2 and CeO 2 . FT-IR spectra of the spent catalysts revealed that glycerol and 2-cyanopyridine could be activated on CeO 2 -based catalysts, and an ester intermediate was formed for the production of glycerol carbonate. Thus, a plausible mechanism is proposed for the synthesis of glycerol carbonate from glycerol and CO 2 in the presence of 2-cyanopyridine in DMF solvent over CeO 2 -based catalysts. Moreover, the recyclability of Ce 0·98 Zr 0·02 O 2 was measured and the catalysts could be regenerated through a simple calcination process at 400 °C for 5 h in air.
研究领域:
化学工程
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催化材料
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2017
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IF 5.951
Qiangqiang Zhu,Chun Shen,Jie Wang,Tianwei Tan
The upgrade of acetone–butanol–ethanol (ABE) mixture from biomass to high-value biofuels has aroused increasing attention. However, a reported heterogeneous catalyst, metal-containing MgAl-hydrotalcite (HT), is confronted with a serious water-resistance problem due to an inherent memory effect of HT materials. With the aim of exploring catalysts with improved water-resistance, metal-containing MgO–SiO2 catalysts were synthesized and evaluated. An investigation on the effect of metal type including Ni, Cu, Fe, Zn, and Co, metal loading, and reaction temperature on catalytic performance indicates that the 10 wt % Ni–MgO–SiO2 catalyst provides the best catalytic performance, giving a yield of 81.5% to C5–C15 ketones and alcohols at 240 °C. As expected, the catalyst exhibits an excellent water-resistance. It could tolerate up to 3 wt % water, which was much higher than 0.5 wt % over that of Cu- or Pd-HT as reported. Results from XRD and 29Si MAS NMR analyses indicate that the high water-resistance could be ascribed to the more stable structure of magnesium silicates formed in the catalyst than HT materials. For a further study of the effect of catalyst property on catalytic performance, 10 wt % Ni–SiO2, 10 wt % Ni–MgO, and 10 wt % Ni–MgO–SiO2 catalysts were investigated and characterized. Results from CO2-TPD, pyridine-IR, and NH3-TPD analyses reveal that the catalytic performance is significantly affected by an acid–base property. Obtaining a high catalytic performance necessitates a cooperation of enough acidic sites and basic sites.
研究领域:
催化化学
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可再生资源与环境科学
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产品关联
DOI
高影响因子
ORGANIC PROCESS RESEARCH & DEVELOPMENT
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2018
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IF 3.584
Jie Zhang,Lei Wang,Chuang Li,Shaohua Jin,Changhai Liang
Direct selective hydrogenolysis of dibenzofuran (DBF) derived from coal and shale oil to a value-added chemical, ortho-phenylphenol (OPP), with high selectivity (80%) and yield (48%) has been achieved over Pt/MgO at 400 °C and 1.0 MPa by controlling the C–O bond cleavage as well as minimizing the extent of hydrogenation of aromatic rings. Meanwhile, Pt/SiO2, Pt/Al2O3, and Pt/MgO/Al2O3 catalysts were used for the DBF hydrogenolysis and showed lower selectivity for OPP. The influence of reaction parameters has been studied to unveil the optimal reaction conditions. And the phenomenon of OPP dehydrogenation is found over various catalysts for the hydrogenation reaction of OPP. Extensive reactions and catalyst characterizations demonstrated that the OPP selectivity and the dehydrogenation of OPP to DBF follows the order of supports basicity: MgO-900 > MgO > SiO2 > MgO/Al2O3 > Al2O3, which shows that the acid–base properties of supports impact the adsorption and desorption behaviors of DBF and OPP, and results in the disparity of OPP selectivity and the dehydrogenation of OPP. Finally, a plausible reaction pathway and mechanistic understanding are proposed.
研究领域:
催化化学
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能源化学
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2021
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IF 3.764
He Han,Min Liu,Hong Yang,Chuan Shi,Shutao Xu,Yingxu Wei,Zhongmin Liu,Chunshan Song,Xinwen Guo
One of the potential processes for making styrene monomers is side-chain alkylation of toluene with methanol, and X zeolites (a common type of faujasite) have been identified as one of the most suitable catalysts for this reaction. In this work, a series of X zeolites with different micro- and meso-porosities and acid–base properties are prepared by post-treatments of NaX zeolite and their catalytic performances for the side-chain alkylation of toluene with methanol are evaluated. This study shows that intracrystalline mesopores could be introduced into the NaX zeolite while retaining adequate microporosity through controlling the intensity and sequence of ammonium-exchange (AE) and/or dealumination (DA) post-treatments. The loss in basicity of the resulting mesoporous X zeolites due to AE and/or DA treatments could be compensated and even enhanced by the subsequent cesium modifications. As catalysts for the side-chain alkylation reaction, the study shows that while introducing appropriate mesopores into X zeolites enhances molecular diffusion, the restriction effect of micropores is proven to be critical for their catalytic activity. Moreover, it is the acid–base property rather than the pore structure of the post-treated X zeolites determining their catalytic activity and selectivity for the side-chain alkylation reaction.
研究领域:
化学工程
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催化科学
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产品关联
DOI
高影响因子
Molecular Catalysis
·
2025
·
IF 4.9
Faraz Ahmad,Yueli Wen,Muhammad Zeeshan,Bin Wang,Samia Kausar,El Gharrabi Mohamed,Wei Huang
Achieving an optimal acid-base synergy and uniform dispersion of active sites on catalyst surface is essential for high catalytic performance in the side chain alkylation of toluene with methanol (SATM). Herein, we report that ammonium (NH₃) treatment of Cu-modified NaX zeolite catalysts effectively modulates acid-base properties and enhances the dispersion of Cu active sites across the catalyst surface. A series of Cu-modified catalysts were prepared with and without NH₃ treatment and further modified with NaOH to evaluate their synergistic effects. Comprehensive characterization techniques, including Scanning Electron Microscopy (SEM), HAADF-STEM and EDS, Pyridine FTIR, Temperature-Programmed Desorption of NH₃ (TPD-NH₃), X-ray Photoelectron Spectroscopy (XPS O 1 s), and regression analysis, were used to correlate catalyst structure, and acid-base property and nature of acid sites with catalytic performance. Results reveal that NH₃ incorporation into the Cu-modified NaX framework significantly enhances catalytic efficiency by tuning acid-base properties and promoting a homogeneous distribution of Cu active sites. Notably, the 3Cu-4Na-N catalyst achieved a superior yield of ethylbenzene and styrene production, reaching 84.9 %, compared to 64.3 % for the 3Cu-4Na catalyst under identical conditions. Methanol conversion reached 97.7 %, with the catalyst demonstrating robust stability over 168 h of operation. Additionally, 3Cu-4Na-N catalyst exhibited the highest turnover frequency (TOF) reaching 27.3 h -1 , confirming its superior intrinsic activity. This study highlights the critical role of NH₃ in advancing Cu-NaX catalysts for SATM and provides a promising strategy for optimizing catalytic performance through controlled acid-base interactions and active site dispersion.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
De-Hui Sun,Ji-Lin Zhang
As artificial nano-enzymes and effective adsorbents, CeO 2 nanomaterials have been extensively studied for their potential applications in biomedicine and environmental protection. However, the surface acid-base properties of nanoceria suspensions have not been fully studied. In this work, the ceria nanoparticles were synthesized by hydrothermal reaction and calcination . They have a BET specific surface area of 52.01 m 2 /g. FTIR and XPS showed that there are two amphoteric sites (≡Ce(IV)-OH and ≡Ce(III)-OH) and a trace acidic site (≡Ce(III)-OCOOH) which can act as a site probe. The pH range of the acid-base reaction of surface hydroxyl groups of the CeO 2 nanomaterials was determined by Gran plot method. The acidic ionization constants (log K 1 , log K 2 ), site concentration (log C) of two amphoteric surface hydroxyl sites and pH pzc in three KNO 3 supported electrolytes were simultaneously optimized by ProtoFit GUI v2.1 free software using Donnan Shell Model (DSM) and same initial parameters. Their surface species distribution was calculated by PHREEQCI 3.4.0 free software using Donnan model and database (phreeqc.dat). The results show that the proton transfer reaction occurred between ≡Ce(IV)-OH and ≡Ce(III)-OH sites. Therefore, this study reveals the surface acid-base properties, proton transfer behavior and pH pzc of the CeO 2 suspension.
研究领域:
纳米医学
·
环境化学
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胶体与界面化学
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生物材料
·
分子环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）