RENEWABLE ENERGY
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2021
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IF 8.001
Shanshan Shao,Chengyue Liu,Xianliang Xiang,Xiaohua Li,Huiyan Zhang,Rui Xiao,Yixi Cai
Catalytic conversion of pyrolysis vapor from biomass was performed over CeO 2 catalysts to produce ketones. Thermogravimetric-gas chromatography/mass spectrometry (TG-GC/MS) and TG-MS were applied to understand the distribution of pyrolysis vapors from various biomass including rape straw, poplar, cypress and bagasse. The favorable biomass feedstock with high yield of ketones and other useful components were screened out for directional ketonization. The results showed that the temperature range of biomass pyrolysis was generally below 400 °C, and bagasse was a reasonable raw material for ketonization with the highest yield of ketones of 33.68% at 380 °C, since it contained the most cellulose and hemicellulose in biomass of the same quality. The activity of acetone increased at higher temperature, and secondary reaction occurred, resulting in a reduction in the overall yield of ketones. The total yield of ketones from bagasse treated for 9 h was boosted by 16.18% higher than that from nonseawater-treated biomass. By the introduction of metal ions effectively, the component of the pyrolysis vapor changed, making it easier for large molecular substances to be converted to small ones during pyrolysis. Through this research, the effective utilization of biomass could be realized.
研究领域:
能源与环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2021
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IF 5.816
Xianglei Liu,Chuang Bao,Zhonghui Zhu,Hangbin Zheng,Chao Song,Qiao Xu
Methanol steam reforming (MSR) is considered as an effective method for hydrogen storage and generating high-quality hydrogen for fuel cells. In this work, mesoporous Cu/TiO 2 –CeO 2 catalysts are proposed to achieve efficient MSR based on synergetic effects of thermal and photon energies . Optimal Ti/Ce molar ratio is found to be 2:1, for which excellent methanol conversion of 100% and extremely low CO selectivity of 2.2% are achieved for thermal catalysis. Further applying UV light (280–400 nm) irradiation while keeping the same temperature, the hydrogen production rate is enhanced to be 78.8 mmol/h/g from 58.6 mmol/h/g. The underlying mechanism is attributed to photogenerated electron hole pairs promoting the REDOX reaction of intermediate product methyl formate based on in situ diffuse reflectance infrared fourier transform spectra (DRIFTS). This work provides a new method to enhance methanol steam reforming performance via thermo-photo synergic effects, and paves a way for the development of direct solar driven MSR techniques.
研究领域:
化学工程
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催化材料科学
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
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2020
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IF 7.216
Shuangxi Lin,Ziwen Hao,Jindong Shen,Xiao Chang,Shouying Huang,Maoshuai Li,Xinbin Ma
The metal-support interaction is of critical importance to enhance the catalytic activity and selectivity. However, it is still challenging to construct an appropriate interaction starting from the catalyst fabrication and/or activation. We herein established low-temperature treatment of Ni 2+ ions impregnated on ceria in reductive atmosphere and reduction–oxidation cycles as effective approachs to regulate the metal-support interaction and raise the catalytic performance in the CO 2 methanation. The proposed construction approach yielded Ni/CeO 2 that displayed highly dispersed Ni nanoparticles in contact with CeO 2 (111) and (100) facet, higher density of surface oxygen vacancies and larger amounts of weak basic sites relative to the reference samples, which increased the capacity for H 2 and CO 2 adsorption/activation. The interaction resulted in appreciably (2–3 fold) higher activity in the CO 2 methanation with maintaining almost full selectivity to CH 4 and high stability. Coverage of Ni surface by CeO 2− x thin layer as a typical structure of strong metal-support interaction resulting from high-temperature reduction, can be alleviated via reduction–oxidation cycles. We also demonstrate the activation treatment-determined metal-support interaction effect can generally extend to (TiO 2 and ZrO 2 ) supported Ni catalysts.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
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2022
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IF 8.035
Ji Zhao,Xian-Yong Wei,Jing-Hui Lv,Qian-Qian Kong,Jia-Hao Li,Zhuang Li,Zi-Chun Fan,Li Li,Yang-Yang Zhang,Zhi-Min Zong
Ni/CeO 2 with medium-strong acidity was prepared by in - situ carbon templating (ISCT) and reduction with H 2 . Oxydibenzene (ODB) and benzyloxybenzene (BOB) were used as lignin-related model compounds (LRMCs). Over Ni/CeO 2 , ODB was completely converted into cyclohexane ( CH I ) under initial hydrogen pressure (IHP) of 2 MPa at 160 °C for 2 h and complete conversion of BOB to CH I and methylcyclohexane (MCH) was achieved under IHP of 2 MPa at 120 °C for 1.5 h. H … H transfer to the benzene rings (BRs) in the LRMCs and phenol from BOB hydrocracking results in the BR hydrogenation, while H + transfer to the oxygen atom in BOB, hydrogenated ODB, and BOB-derived cyclohexanol ( CH II ) leads to the >CH-O- bond cleavage and subsequent dehydration of the resulting protonated CH II (PCH II ) . In addition, Ni/CeO 2 exhibits an excellent reusability.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
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2016
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IF 9.307
Zhixin Zhang,Yehong Wang,Jianmin Lu,Chaofeng Zhang,Min Wang,Mingrun Li,Xuebin Liu,Feng Wang
Conversion of low-carbon olefins to higher alcohols or olefins via the formation of C–C bonds is an increasingly important topic. We herein report an example of converting isobutene and formaldehyde (38 wt % aqueous solution) to 3-methyl-1,3-butanediol (MBD), a precursor for isoprene. The reaction occurs through a Prins condensation–hydrolysis reaction over a praseodymium (Pr)-doped CeO2 catalyst. The best MBD yield (70%) is achieved over the Pr-doped CeO2 catalyst. Catalyst characterizations with high-angle annular dark field transmission electron microscopy (HAADF-TEM), pyridine adsorption infrared (IR) and Raman spectroscopy, and density functional theory (DFT) calculations show that the doped Pr is uniformly and highly dispersed in the CeO2 crystalline phase. In addition, the Pr doping creates more oxygen vacancy sites on CeO2 and thus enhances the Lewis acidity of the catalyst, which is responsible for the catalytic performance of the Pr-CeO2 catalyst.
研究领域:
催化化学
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材料科学
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有机合成
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2024
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IF 8.1
Yunzhu Wang,Yang Chen,Songshan Zhu,Di Song,Tianhao Ai,Sufang He,Yongming Luo
Steam reforming of glycerol (GSR) to produce hydrogen has been considered a sustainable and low-cost route for hydrogen production. The selection of a suitable catalyst support is crucial for achieving efficient hydrogen production at lower temperatures. CeO 2 has been widely used in heterogeneous catalysis and exhibits excellent low-temperature catalytic performance. However, different calcination mode may influence catalyst performance. In this study, the Ni/CeO 2 catalyst prepared by rapid calcination mode (Ni/CeO 2 -RC), was used for hydrogen production from GSR, and the Ni/CeO 2 catalyst with the conventional programmed-heating calcination method (Ni/CeO 2 -PC) was applied for comparison. The effect of different calcination modes on the physico-chemical properties of the catalysts was investigated through multiple characterizations such as N 2 adsorption-desorption, X-ray diffraction, hydrogen temperature programmed reduction, transmission electron microscopy, X-ray photoelectron spectroscopy, H 2 chemisorption, CO-oxygen storage capacity and conversion, temperature programmed oxidation, and Raman spectroscopy. The rapid calcination mode promoted stronger metal-support interactions in Ni/CeO 2 -RC, inducing the formation of nickel species highly susceptible to reduction due to the electronic effect. Additionally, rapid calcination facilitated the increased incorporation of nickel particles into the cerium dioxide lattice, leading to lattice distortions, thereby contributing to the formation of more oxygen vacancies. The abundant oxygen vacancies promoted the activation of water, thus realizing the high H 2 selectivity of Ni/CeO 2 -RC. Moreover, the strong oxygen storage-release ability of Ni/CeO 2 -RC facilitated the oxidative effect of carbon deposition and the strong Ni–CeO 2 interaction effectively inhibit sintering of nickel nanoparticles on Ni/CeO 2 -RC. Therefore, Ni/CeO 2 -RC exhibited outstanding catalytic stability, remaining active for 35 h without deactivation, whereas Ni/CeO 2 -PC rapidly deactivated after 25 h of reaction.
研究领域:
催化化学
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能源材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Engineering Au
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2022
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IF 0
Huanhao Chen,Wei Guo,Xiaolei Fan
Non-thermal plasma (NTP) catalysis is a promising technology for CO2 valorization with renewable H2, in which catalyst design is one of the key aspects to progress the hybrid technology. Herein, bimetallic NiCo supported on CeO2 catalysts, that is, NiCo/CeO2, were developed with less metal loading of ∼2 wt % using mechanochemical synthesis for NTP-catalytic CO2 methanation. During the synthesis, different addition orders of Ni and Co precursors were investigated, and the results show that the NiCo1/CeO2-I catalyst (which was prepared by the simultaneous addition of Ni and Co precursors, protocol I) exhibited the highest CO2 conversion (∼60%) and CH4 selectivity/yield (∼80%/∼50%), whereas the NiCo1/CeO2-II and NiCo1/CeO2-III catalysts (prepared by sequential addition protocols of II and III) showed very poor catalytic performance. Characterization results suggested that in protocol I, Ni and Co prefer to alloy, and concentrated oxygen vacancies on the CeO2 surface and high surface basicity are retained as well. Such properties of NiCo1/CeO2-I were responsible for CO2 activation and hydrogenation under NTP conditions, which was explained by the proposed mechanisms.
研究领域:
化学工程
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环境科学
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材料科学
✓ 已验证
DOI
APPLIED SURFACE SCIENCE
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2025
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IF 6.9
Jiabing Chen,Xiaowei Zhu,Mengheng Wang,Xingmao Jiang,Xiaojun Lu
The reaction rate of alkoxycarbonylation is typically lower when using heterogeneous catalysts compared to homogeneous catalysis, primarily due to the reduced ability of the active sites to activate the reactants. To address the insufficient activation of reactants on the Ru/CeO 2 catalyst for ethylene methoxycarbonylation, this study investigates the doping of CeO 2 with Pr 3+ ions. By substituting Ce 4+ with Pr 3+ in the CeO 2 , richer oxygen vacancies are generated, which enhance the activation of CH 3 OH. This doping significantly increases the reaction rate of ethylene methoxycarbonylation to methyl propionate (MP), achieving a rate of 86.1 g·g Ru -1 ·h −1 while maintaining a selectivity of over 99 %. Notably, Pr doping also induces the formation of Ru-O-Ce species in the catalyst, which hinders the reduction of Ru species. However, this hindered reduction is counterbalanced by the enhanced dispersion of Ru species, as Pr doping promotes the formation of smaller Ru nanoparticles. Thus, an optimal level of Pr doping exerts a synergistic effect by positively influencing both the CeO 2 support and the Ru metal, thereby improving their respective abilities to activate the reactants and enhancing the overall performance in the ethylene methoxycarbonylation reaction to produce MP.
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
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
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2024
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IF 5.3
Jiabing Chen,Yibo Tang,Xingmao Jiang,Rui Zhang,Xiaojun Lu
In this work, Ru–CeO2 prepared by a “melting” method and used as a heterogeneous catalyst for ethylene methoxycarbonylation was investigated, together with two other catalysts prepared by impregnation and aerosol methods. The Ru–CeO2 (1%-M) catalyst demonstrates activity significantly higher than that of the other catalysts with the same Ru content. The XPS and Raman analysis results suggest that the Ru–CeO2 (1%-M) oxygen vacancy content is not the highest among the catalysts prepared using the three methods, even though the content oxygen vacancies have been reported to play a crucial role in carbonylation when using a Ru–CeO2 catalyst. It was discovered that the available Ru0 (Ru0 in the freshly prepared sample plus that being transformed from Run+ during reduction) is the other decisive factor in determining the catalyst’s performance. We further investigated the high reducibility of the catalyst prepared by using the melting method and discovered that a weak metal–support interaction could be obtained because of the independent formations of Ru and CeO2 crystals with graphite carbon as the barrier. Removing carbon under the optimal conditions could facilitate the as-formed Ru crystals anchored onto CeO2; therefore, there is no strong interaction between Ru and CeO2.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2021
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IF 19.503
Pengchao Ren,Weifeng Tu,Chanchan Wang,Sifan Cheng,Wenqi Liu,Zhenzhou Zhang,Yun Tian,Yi-Fan Han
This study investigated the Cu-CeO 2 interactions for CO hydrogenation to methanol by applying rate measurements, chemical titration/desorption, together with in-situ/operando spectroscopy techniques under realistic reaction conditions. Ce components were enriched in the surface region of Cu/CeO 2 catalysts while Ce 3+ and Ce 4+ atoms co-existed during CO hydrogenation. The ratio of Ce 3+ to Cu 0 in the surface region of catalysts increased linearly with the Ce content. The turnover rates of CH 3 OH formation increased as a single-valued function of the ratio, irrespective to the individual contact extent between Cu and CeO 2 clusters or Ce content in the Cu/CeO 2 catalysts, indicating that the Cu 0 -Ce 3+ sites pair acts as active sites for CO hydrogenation to methanol over Ce-CeO 2 samples. This study also unraveled that formyl and formate species, as reactive surface intermediates, were co-adsorbed on the Cu 0 -Ce 3+ sites, and their hydrogenation routes occurred concurrently for CH 3 OH formation during CO-H 2 reactions.
研究领域:
催化
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化学工程
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表面科学
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2025
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IF 2.5
Lu Ji,Conghui Che,Fang Li,Wei Xue,Xiaoshu Ding,Dongsheng Zhang,Jing Li,Xinqiang Zhao,Yanji Wang
Methoxycarbonylation of aniline (AN) with dimethyl carbonate (DMC) to produce methyl N-phenylcarbamate (MPC), a key intermediate in non-phosgene diphenylmethane diisocyanate (MDI) synthesis, is facilitated using a newly developed CuO–CeO2 catalyst. This catalyst demonstrated a high AN conversion rate of 95.1% and an MPC selectivity of 92.7% at an nDMC/nAN ratio of 10. The catalyst's effectiveness is attributed to the synergistic interaction between CuO and CeO2, which enhances oxygen vacancy generation and increases the acid amount, as well as Lewis acid sites. Weak Lewis acid sites are conducive to MPC synthesis. There are three distinct copper species present in the CuO–CeO2 catalyst, among which the copper species doped into the CeO2 lattice is beneficial to MPC synthesis. The deactivation of the catalyst, due to the reduction of CuO by methanol, and catalyst regeneration through calcination are discussed. The catalytic mechanism is explored with in situ FT-IR, providing deeper insight into the methoxycarbonylation process.
研究领域:
化学工程
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催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
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2024
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IF 5.2
Fanhui Liao,Yanchang Chu,Donghai Xu,Le Yang
Co/CeO2 catalysts with different morphologies of polyhedrons (Co/CeO2–P), rods (Co/CeO2–R), sheets (Co/CeO2–S) and cubes (Co/CeO2–C) were prepared and compared on the catalytic upgrading of hydrothermal liquefied (HTL) biocrude derived from municipal sewage sludge (MSS) to biofuel. The best quality biofuel was achieved on Co/CeO2–C with a higher heating value (HHV) of 39.10 MJ/kg, where the sulfur and oxygen contents were reduced to 0.007 and 9.19 wt %, while the carbon and hydrogen contents were elevated to 77.5 and 10.1 wt %, respectively. In contrast, the pure ceria support presented a slight improvement for the upgrading of biocrude. Overall, this work provides a feasible solution for high-value utilization of MSS to produce high-grade biofuel.
研究领域:
环境科学
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化学工程
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能源技术
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催化
✓ 已验证
产品关联
DOI
高影响因子