JACS Au
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2025
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IF 8.7
Xuan Bie,Yukun Pan,Xiaowei Wang,Shiyu Zhang,Jiahui Hu,Xiaoxiao Yang,Qinghai Li,Yanguo Zhang,Robert E. Przekop,Yayun Zhang,Hui Zhou
Gas sources rich in CO2 derived from biomass/waste gasification, anaerobic digestion, or industrial carbon capture often contain impurities such as H2S, H2O, and NH3, which can significantly hinder catalyst performance. Here, we show the role of NH3 on the reverse water–gas shift (RWGS) reaction over a commercial Cu/ZnO/Al2O3 catalyst, examining its effects on both the catalytic activity and the catalyst structure. We found that NH3 reversibly decreases CO2 conversion immediately by suppressing carbonate hydrogenation and CO desorption. This effect intensifies with an increase in NH3 concentration but decreases at higher temperatures. However, prolonged exposure (over 100 h) to RWGS conditions in the presence of 1.4% NH3 leads to near-total and irreversible deactivation of the Cu/ZnO/Al2O3 catalyst. Under NH3 exposure, the catalyst loses Cu+ sites on the surface, causing a spatial separation of Cu and ZnO. Finally, to address this challenge, we propose a novel strategy to mitigate NH3 inhibition by decomposing NH3 into N2 and H2.
研究领域:
化学工程
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催化科学
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环境科学
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产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
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IF 20.2
Haitao Yan,Didi Li,Zhaocong Jiang,Haoyuan Gu,Mengyuan Zhu,Yi-Fan Han,Minghui Zhu
Cu-based catalysts have been extensively used in the methanol steam reforming (MSR) reaction owing to low cost and high efficiency. In this work, we investigated the promotional effect of Fe on the Cu/ZnO/Al 2 O 3 catalysts prepared by an incipient-wetness impregnation method using a series of (quasi) in situ characterization techniques. The form of the Fe species was found to strongly depend on the Fe content. Fe species are present as highly dispersed FeO x in small amount of Fe with improved the dispersion of Cu. As Fe content increases, Fe species gradually transition to CuFe alloy and eventually to Fe 3 O 4 particles, leading to a decrease in Cu dispersion. With the gradual increase in Fe content, the apparent activity shows a volcanic trend, with CuAl-0.1Fe showing highest activity, whereas the intrinsic activity gradually decreases. Compared with CuAl- x Fe, adding moderate Fe to Cu/ZnO/Al 2 O 3 promotes the dispersion of Cu and Zn, forming abundant Cu-ZnO x interfacial sites, which improves both apparent and intrinsic activities. The best catalytic performance was obtained with the CuZnAl-0.1Fe catalyst, achieving the highest H 2 production rate of 134.7 mmol g cat −1 h −1 at 200 °C. This study reveals the role of Fe in Cu-based catalysts for MSR and inspires the design of improved Cu-based 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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2024
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IF 8.1
Guiming Xie,Xingyang Bai,Yanrui Niu,Zhangjun Bai,Qingyuan Yang,Jian Liu,Zhou-jun Wang
ZIF-8 was employed as partial Zn source to prepare high-performance Cu/ZnO/Al 2 O 3 catalysts for methanol synthesis via carbon dioxide (CO 2 ) hydrogenation. Among the CuZnAl-x catalysts (x = 1, 0.75, 0.5, 0.25 and 0, denoting molar ratio of ZIF-8/(ZIF-8 + Zn(NO 3 ) 2 ·6H 2 O), the CuZnAl-0.5 catalyst possessed the highest space time yield of methanol ( STY MeOH ), which recorded 416.4 g MeOH kg cat −1 h −1 at 250 °C and 3.0 MPa. Using ZIF-8 as partial Zn source was found to increase the specific surface area, induce oxygen vacancies, intensify metal-oxide interactions and enrich medium basic sites, which may rationalize the excellent methanol synthesis activity of the CuZnAl-0.5 catalyst. Besides, the CuZnAl-0.5 catalyst showed good stability for 30 h of reaction. This work offers a unique route to fabricate catalysts with the aid of MOFs precursors and highlights the significance of oxygen vacancies in methanol synthesis catalysts.
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
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Xiaoxia Zhang,Zhipeng Zhou,Junjie Liao,Liping Chang,Jiancheng Wang,Weiren Bao
The ultra-deep removal of thiophene from coke oven gas (COG) is critical for the conversion of COG to methane. Currently, Cu/ZnO/Al 2 O 3 is considered as a promising sorbent for thiophene removal; however, its desulfurization performance is currently unable to meet the requirements for industrial applications. Here, a zirconium modification strategy is proposed to overcome this problem, allowing zirconium loaded copper-based sorbents (Cu/ZnO/Al 2 O 3 /ZrO 2 ) with significantly improved thiophene removal performance and high activity to be obtained. Characterization results showed that zirconium improved both the dispersion of copper and the concentration of Lewis acid sites on the sorbent surface. A ZrO 2 concentration of 2 % resulted in stronger Cu-Zn interaction, and the dispersion of Cu on the surface of the sorbent reached its maximum value (49.20 %). Additionally, the Lewis acid strength was also maximized, which greatly improved the desulfurization activity and resulted in a breakthrough adsorption capacity of thiophene (Q b-thiophene ) of 36.24 mg/g, which was about 17 % higher than that of the unmodified Cu/ZnO/Al 2 O 3 sorbent. These results demonstrate that the sulfur capacity of the sorbent can be increased by increasing the number of acidic sites on its surface, paving the way for ultra-deep thiophene removal in industrial applications.
研究领域:
化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2023
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IF 22.1
Xiaojing Cui,Yequn Liu,Wenjun Yan,Yanfeng Xue,Yangang Mei,Jiamei Li,Xiaoqing Gao,He Zhang,Shanhui Zhu,Yulan Niu,Tiansheng Deng
Suppressing reverse water-gas-shift (RWGS) reaction is high desirable but challenging and underdeveloped for Cu/ZnO catalysts, particularly for commercial Cu/ZnO/Al 2 O 3 catalysts. Different from the current methodologies to reduce RWGS reaction, we report a simply surface silylation method for efficiently minimizing RWGS reaction over a commercial Cu/ZnO/Al 2 O 3 catalyst. This method suppresses STY CO (Space-time yield) from 97.4 to 0.7 g CO ·kg cat −1 ·h −1 , improving STY MeOH from 20.2 to 39.9 g MeOH ·kg cat −1 ·h −1 and methanol selectivity from 15.1 to 92.9 mol%. The combination of characterization methods and density functional theory calculations provide insight into the suppressing mechanism of surface silylation on catalyst. A hydroxyl (on ZnO)-promoted RWGS reaction cycle is discovered, which can be efficiently inhibited by the consuming of hydroxyls via surface silyation. Our results provide a way to regulate RWGS reaction on Cu/ZnO-based catalysts and are expected to the further use of silylation strategy to tune the interconversion of CO and CO 2 via RWGS/WGS reaction on hydrogenation catalysts.
研究领域:
催化化学
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材料科学
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理论计算化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Shubin Cheng,Qian Lei,Coner Deng,Weixin Lei,Honglin Chen
A green protocol for refining industrial chemicals containing formaldehyde (FA) impurities is presented here for the first time. FA, as an unreactant or a byproduct, causes separation problems in many industrial processes. It can be removed to a level of less than 1 ppm with easily separable methanol formation using commercial Cu/ZnO/Al 2 O 3 catalyst at atmospheric pressure in the absence of external hydrogen. The formation of methanol is achieved by the transfer of hydrogen species generated with the assistance of water to free FA, affording high methanol selectivity (62 %). By investigating potential intermediates and implementing deuterium labeling experiments, together with carbon and hydrogen balance calculations, a plausible pathway of water-assisted FA removal is proposed. Moreover, the in situ generated hydrogen species can be transferred directly into unsaturated compounds for selective reduction.
研究领域:
化学工程
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催化
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环境化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2023
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IF 4.7
Yong Liu,Xinghua Zhang,Lungang Chen,Jianguo Liu,Qi Zhang,Longlong Ma
This study explores the efficacy of a cost-effective Cu-ZnO-Al 2 O 3 catalyst for one-pot hydrodeoxygenation of guaiacol into hydrocarbons. Notably, complete conversion of guaiacol was achieved, yielding a 99.6% hydrocarbon over the robust Cu(6)Zn(3)Al(1) catalyst under the conditions of 4 MPa H 2 , 300 °C, and 8 h with a catalyst/guaiacol ratio of 0.5 g/1.0 g. In-depth catalyst characterizations unveiled the presence of oxygen vacancies within the ZnO surface layer, acting as pivotal active sites that facilitated the hydrodeoxygenation of guaiacol. Furthermore, Density Functional Theory (DFT) calculations were employed to evaluate several potential active sites, revealing that the oxygen vacancy of ZnO on the Cu surface played a crucial role. This vacancy enhanced the adsorption of intermediate cyclohexanol and markedly reduced the energy barrier for the rate-limiting step. This comprehensive investigation sheds light on the catalytic pathway and offers insights into designing efficient and sustainable biofuel production processes.
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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能源
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2020
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IF 7.632
Qian Wang,Zhi Yu,Junting Feng,Paolo Fornasiero,Yufei He,Dianqing Li
The production of biofuel 2,5-dimethylfuran (DMF) from an important biomass platform of 5-hydroxymethyl furfural (HMF) involves a complicated reaction pathway due to the competition of C═O hydrogenation and C–O hydrogenolysis; however, the dependence of formed intermediates and catalytic sites needs to be further identified. Herein, we constructed a highly efficient and selective Cu/ZnO-Al2O3 catalyst via reduction of a CuZnAl-layer double hydroxide (LDH) precursor, aimed for studying the effect of Cu0/Cu+ species on forming different intermediates and their synergetic promotional effect on HMF hydrodeoxygenation. As expected, the dependence of formation of different intermediates on the Cu+/Cu0 ratio was observed; notably, Cu/ZnO-Al2O3 with higher Cu+/Cu0 ratio finally gave 90.1% DMF selectivity at 100% HMF conversion, more selective than CuNi/Al2O3 (59.6%) and Cu/MgO-Al2O3 (75.8%) references. By a combined study of in situ IR experiments, the observed correlation between the reaction intermediates and the Cu0/Cu+ site suggests that Cu0 tends to adsorb the C═O bond as well as hydrogen molecule, while the Cu+ site is preferable to adsorb and activate the C–O bond. With the synergy of dual active sites, the Cu/ZnO-Al2O3 catalyst showed both high activity and selectivity to DMF. This work provides deep insight into the nature of active Cu species in multiple functional group biomass platform transformation.
研究领域:
催化
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化学工程
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生物化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2015
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IF 2.587
Jie Sun,Shaolong Wan,Fen Wang,Jingdong Lin,Yong Wang
A variety of catalysts for higher alcohol synthesis from syngas have been under development for potential commercial application, which are still facing challenges, including poor carbon efficiency due to low selectivity to desired products. In this contribution, we systematically studied the effects of temperature, loading of K and Cs, space velocity, and CO2 addition on the alkali-promoted Cu/ZnO/Al2O3 catalysts in order to achieve a high yield of desired higher alcohol products. Our particular focus was to maximize the carbon efficiency by restricting the amount of undesired byproducts, such as lower alkanes and CO2 that could be formed. Among K and Cs promoted Cu/ZnO/Al2O3 catalysts studied, Cs-promoted Cu/ZnO/Al2O3 catalysts exhibit better performance to higher alcohols and higher carbon efficiency than K-promoted counterparts under similar conditions studied. 1.64 mol % Cs-promoted Cu/ZnO/Al2O3 catalyst achieves the highest selectivity to higher alcohols (24.9%) at a CO conversion of 41.6% under 290 °C, 1875 mL g–1cat h–1, 5.4 MPa. The presence of a small amount of CO2 of 2.5 mol % in the feed has negligible effect on the productivity of higher alcohols but significantly suppresses the formation of CO2 byproduct. With the further increase of CO2 in the feed, the formation of CO2 can be further suppressed but at the expense of productivity loss of higher alcohols, which is probably due to the neutralization of surface Cs sites. The best carbon efficiency can be achieved at 8% mol CO2 in the feed.
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
CATALYSIS TODAY
·
2023
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IF 5.3
Hangjie Li,Liang Wang,Feng-Shou Xiao
Cu/ZnO/Al 2 O 3 catalyst has been widely studied in the hydrogenation of CO 2 to methanol, but it still suffers from insufficient catalyst stability and methanol selectivity. Herein, we overcome these issues by introducing the silica promoter to the catalyst, achieving the Cu/ZnO/Al 2 O 3 /SiO 2 (CZAS) catalysts with significantly improved methanol selectivity and catalyst durability. Characterizations of samples showed that the silica species efficiently hindered the sintering of Cu nanoparticles during the catalysis, exhibiting constant performances in the continuous tests. In addition, the silica also electronically modulated the Cu nanoparticles that result in abundant Cu δ+ species in the catalyst, which minimized the methanol decomposition to improve the methanol selectivity, compared with the silica-free Cu/ZnO/Al 2 O 3 catalyst. As a result, the CZAS exhibited CO 2 conversion at 12.6 % and methanol selectivity at 85.1 %, giving a one-pass methanol yield at 10.7 %. The strategy in this work might provide an efficient route for enhancing the current industrial catalysts.
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
AICHE JOURNAL
·
2026
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IF 4
Jie Li,Ying Liao,Ming Guo,Yue Pan,Yaqian Li,Xuechao Yang,Yulin Wang,Meiyu Zhang,Mengnan Ma,Xiaobo Chen,Yibin Liu,Hao Yan,Chaohe Yang
Direct dehydrogenation of alcohols to aldehydes is a pivotal transformation in fine chemical synthesis. However, conventional thermal processes often suffer from low efficiency and high energy consumption. Herein, we propose an emerging and sustainable strategy that employs CO 2 -assisted in situ hydrogen extraction to drive the dehydrogenation of alcohols under mild conditions. Specifically, CO 2 as a soft oxidant adsorbs and activates on the Cu–ZnO–Al 2 O 3 composite oxide catalyst surface, generating reactive species (COO*) that selectively abstract hydrogen from the α -C of the alcohol. Combined Langmuir-Hinshelwood kinetic analysis and density functional theory calculations reveal a higher formation rate of the aldehyde product and the lower activation barrier for the key C–H bond activation process under the CO 2 atmosphere. As a result, the CO 2 -assisted dehydrogenation markedly enhances reaction efficiency, achieving a 60.21% conversion of 2-ethylhexanal under a low temperature (240°C), which is nearly twice that observed under the pure N 2 atmosphere. This CO 2 -assisted dehydrogenation strategy in this work exhibits a cooperative catalytic pathway that not only enables efficient aldehyde production but also utilizes CO 2 as a chemical resource.
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Fanjing Wei,Weizhou Jiao,Bo Liu,Hao Qin,Guisheng Qi,Jing Guo,Zhiguo Yuan,Liping Chang,Junjie Liao,Ting Li
Cu-ZnO is a promising sorbent for the removal of thiophene. However, the aggregation and growth of copper grains during the heating reaction leads to the sintering deactivation of the sorbent. Although various strategies have been proposed to introduce supports to mitigate these defects, the impact of supports on the desulfurization performance of sorbent remains poorly understood. In this study, Cu-ZnO/Al 2 O 3 sorbents were synthesized with excellent performance by incorporating Al 2 O 3 (derived from Al(NO 3 ) 3 , γ-Al 2 O 3 and AlOOH as aluminum sources) using co-precipitation and fractional precipitation methods. The thiophene removal evaluation was conducted in a fixed bed reactor. The results indicates that the breakthrough adsorption capacity for thiophene ( Q b-thiophene ) of sorbent synthesized using γ-Al 2 O 3 and AlOOH is approximately 25 % higher than that of those synthesized with Al(NO 3 ) 3 . In comparison to Al(NO 3 ) 3 , γ-Al 2 O 3 and AlOOH exert less influence on the precipitation and crystallization processes of Cu 2+ and Zn 2+ . Sorbents synthesized with γ-Al 2 O 3 and AlOOH as aluminum sources demonstrate higher copper dispersion, larger specific surface area and smaller grain size, all of which significantly enhance the desulfurization activity of sorbent. Furthermore, the use of γ-Al 2 O 3 and AlOOH as aluminum sources contributes to an increase in ZnO and unsaturated Zn δ+ contents on sorbent surface. This improvement enhances hydrogen storage capacity and promotes hydrogen spillover at the Cu-ZnO interface; additionally, it facilitates both the adsorption activation of thiophene and the stable fixation of sulfur species. These findings provide an important theoretical basis for the design and large-scale application of efficient desulfurization sorbents.
研究领域:
化学工程
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材料科学
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环境科学
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无机化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）