CERAMICS INTERNATIONAL
·
2017
·
IF 2.986
Shuaishuai Lu,Jingde Zhang,Yuanyuan Sun,Huichao Liu
CuO-CeO 2 -ZrO 2 /cordierite catalysts have been successfully prepared by the impregnation reduction method. The effects of processing parameters such as the condition of reduction process, calcination temperature, the addition of surfactant on the size and shape of catalyst particles were studied by X-ray diffraction (XRD), BET surface area measurements, and scanning electron microscopy (SEM). The catalytic performance of the as-prepared catalysts for CO oxidation were evaluated by using a microreactor-GC system. The results indicate that the processing parameters influence greatly the size and shape of catalyst particles. Fragmental shape catalysts were formed when the impregnated samples were reduced in the thermostat water bath. However, spherical-like particles were obtained by ultrasonic-assisted in the reduction process. Tiny flower-like catalyst particles were found when the surfactant were used. When the calcination temperature decreased, the grain size of catalysts has reduced, and the catalytic activity for CO oxidation has been improved. The introduction of ultrasonic and surfactant resulted in larger specific surface area and better catalytic performance.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
ACS Catalysis
·
2016
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IF 9.307
Shanhui Zhu,Yanfeng Xue,Jing Guo,Youliang Cen,Jianguo Wang,Weibin Fan
The high-yield synthesis of the biofuel γ-valerolactone (GVL) is a challenging task, which currently stems from the depolymerization of cellulose to levulinic acid, followed by its hydrogenation. We have developed a novel integrated process for the production of GVL from hemicellulose without using liquid acids and external hydrogen. The hemicellulose feed underwent hydrolysis and consecutive dehydration to produce furfural over ZSM-5 catalyst. Subsequently, the formed furfural with 2-propanol performed tandem conversion to GVL over Au/ZrO2 catalyst combined with ZSM-5. This process gave a high yield of GVL under mild conditions: up to 61.5% based on hemicellulose. The outstanding performance was mainly ascribed to the strong interface interaction of Au with ZrO2 species, large amounts of medium-strength acid sites over ZSM-5, and efficient synergy between active metal and acid sites.
研究领域:
生物化学
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催化化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
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IF 13.3
Fan Xu,Xin Meng,Rui Zhao,Daoming Jin,Wenhua Dai,Dandan Yang,Zhong Xin
The utilization of CO 2 for the production of light olefins through catalysis with iron-based catalysts presents a viable strategy to address the challenges of carbon neutrality. In this study, we synthesized a novel hybrid catalyst Fe 2 O 3 @ZrO 2 , derived from the pyrolysis of dual metal–organic frameworks (NH 2 -MIL-88B@UiO-66). Under specific conditions (340 °C, 3.0 MPa, CO 2 /H 2 = 1:3, 10000 mL g cat −1 h −1 ), the Fe 2 O 3 @ZrO 2 catalyst exhibited a notable space–time yield of light olefins at 12.7 mmol g −1 h −1 . The characterizations results show an electron transfer from ZrO 2 to the Fe 2 O 3 surface was observed at the heterointerface of Fe 2 O 3 and ZrO 2 . This electron transfer mechanism was identified as advantageous for the formation of the active phase Fe 5 C 2 . This research introduces an innovative use of the hybrid Fe 2 O 3 @ZrO 2 catalyst derived from MOF-on-MOF, holding significant promise in advancing the field of CO 2 hydrogenation catalysts.
研究领域:
催化化学
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
AICHE JOURNAL
·
2018
·Vol. 64
·期 11
·3988-4001
·
IF 3.326
Xiaowen Zhang,Jieling Hong,Helei Liu,Xiao Luo,Wilfred Olson,Paitoon Tontiwachwuthikul,Zhiwu Liang
In this work, the composite catalysts, SO 4 2 /ZrO 2 /γ-Al 2 O 3 (SZA), with different ZrO 2 and γ-Al 2 O 3 mass ratios were prepared and used for the first time for the carbon dioxide (CO 2 )-loaded monoethanolamine (MEA) solvent regeneration process to reduce the heat duty. The regeneration characteristics with five catalysts (three SZA catalysts and two parent catalysts) of a 5 M MEA solution with an initial CO 2 loading of 0.5 mol CO 2 /mol amine at 98°C were investigated in terms of CO 2 desorption performance and compared with those of a blank test. All the catalysts were characterized using X-ray diffraction, Fourier transform infrared spectroscopy, N 2 adsorption–desorption experiment, ammonia temperature programmed desorption, and pyridine-adsorption infrared spectroscopy. The results indicate that the SZA catalysts exhibited superior catalytic activity to the parent catalysts. A possible catalytic mechanism for the CO 2 desorption process over SZA catalyst was proposed. The results reveal that SZA1/1, which possesses the highest joint value of Brφnsted acid sites (BASs) and mesopore surface area (MSA), presented the highest catalytic performance, decreasing the heat duty by 36.9% as compared to the catalyst-free run. The SZA1/1 catalyst shows the best catalytic performance as compared with the reported catalyst for this purpose. Moreover, the SZA catalyst has advantages of low cost, good cyclic stability, easy regeneration and has no effect on the CO 2 absorption performance of MEA. © 2018 American Institute of Chemical Engineers AIChE J , 64: 3988–4001, 2018
研究领域:
化学工程
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催化材料
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环境科学
✓ 已验证
DOI
高影响因子
BIOMASS & BIOENERGY
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2022
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IF 5.774
Shanshan Shao,Chengyue Liu,Xianliang Xiang,Xiaohua Li,Huiyan Zhang,Rui Xiao
Catalytic upgrading of pyrolysis gas components from cellulose and xylan was investigated over ZrO 2 catalyst to produce aldehydes and ketones . The oxygen content in the bio-oil was reduced by aldol condensation and hydrogenation of aldehydes and ketones. The optimal pyrolysis temperature of cellulose and xylan were determined to be 400 °C and 350 °C and the carbon yields of aldehydes and ketones reached 54.49% and 52.05% respectively. In order to explore the formation mechanism of aldehydes and ketones, the evolution of typical products by controlling the reaction time was studied. The catalytic pyrolysis was complete and the product content was maximum at 20 min H 2 O played a role in providing oxygen atoms and increasing ZrO 2 reaction activity in the carbonylation process. The binding energy of the catalyst was calculated as −15.69 kcal/mol by density functional theory (DFT). It was found that the presence of water can remove the coke on the catalyst surface and increase the activity of ZrO 2 . The yield of aldehydes and ketones reached 58.17% and 55.85% of cellulose and xylan with the presence of 15 wt% H 2 O in the carbonylation process. According to the evolution of the above experimental products, the generation pathways of four main carbonylation products (acetone, methyl ethyl ketone , butyraldehyde and furfural) were proposed. 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
DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2024
·Vol. 99
·期 4
·922-930
·
IF 2.8
Dingshuo Zhang,Heqian Zhang,Yue Li,Daolai Sun,Jianhua Lv
BACKGROUND Levulinic acid is an important platform chemical derivable from lignocellulosic biomass. In this work, the hydrogenolysis of levulinic acid to produce 1,4-pentanediol was performed over some Co-based non-noble catalysts. The relationship between the catalyst properties and the catalytic activity was investigated, and the effects of the reaction conditions on the catalytic activity were studied. RESULTS The Co/ZrO 2 catalyst prepared by a coprecipitation method showed a high catalytic performance in the hydrogenolysis of levulinic acid to form 1,4-pentanediol. The calcination of Co/ZrO 2 significantly affected the catalytic activity, and a high calcination temperature of 750 °C could promote the formation of 1,4-pentanediol. Meanwhile, the reduction of Co/ZrO 2 at 400 °C in an H 2 flow was beneficial for producing 1,4-pentanediol, and the Co species after the reduction existed as the forms of Co 2+ and Co 0 . A high H 2 pressure and a moderate reaction temperature of 200 °C were beneficial for producing 1,4-pentanediol, and a high 1,4-pentanediol selectivity of 85.6% with a complete conversion of levulinic acid was obtained over the Co/ZrO 2 catalyst at 200 °C under an H 2 pressure of 7 MPa. CONCLUSION The Co species in the 400 °C-reduced Co/ZrO 2 catalyst existed as the forms of Co 2+ and Co 0 . It was proposed that the synergistic effect of Co 2+ and Co 0 contributed to the effective formation of 1,4-pentanediol from levulinic acid. © 2024 Society of Chemical Industry (SCI).
研究领域:
化学工程
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可再生能源
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2023
·
IF 22.1
Decun Luo,Ziyu Tang,Xiyang Yu,Tao Zhang,Chun-Ran Chang,Zhun Hu
The effect of ZrO 2 crystalline phases on Pd/ZrO 2 for catalytic combustion of toluene was investigated. It was found that Pd/t-ZrO 2 showed superior activity when the toluene concentration was lower than 2000 ppm, while Pd/m-ZrO 2 performed better with toluene concentration higher than 3000 ppm. Kinetic studies showed that the reaction order of toluene on Pd/t-ZrO 2 and Pd/m-ZrO 2 is 0 and 2, respectively. The catalytic activity was controlled by combined effect of PdO activity and quantity, which was correlated with the interaction between palladium and zirconia. The t-ZrO 2 increased PdO species activity, while m-ZrO 2 could enhance the amount of PdO. DFT results showed that the p-band center of the O of PdO on t-ZrO 2 was higher, suggesting that PdO was more active. In situ -DRIFTS revealed that the reaction pathway of catalytic oxidation of toluene on Pd/ZrO 2 was as follows: toluene was oxidized stepwise to benzyl alcohol, benzaldehyde, benzoic acid , CO 2 and H 2 O.
研究领域:
催化化学
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环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2018
·
IF 11.698
Meng Zhang,Junfeng Zhang,Yingquan Wu,Junxuan Pan,Qingde Zhang,Yisheng Tan,Yizhuo Han
Carbon deposition on the catalyst surface has been considered as one of the main reasons to cause Ni catalyst deactivation during methane reforming with carbon dioxide (DRM). Generally, it is thought that the properties and levels of coke formation are significantly affected by the ability of CO 2 adsorption and activation, which is closely related to the oxygen species over catalyst surface. In this study, the effects of oxygen species on the DRM over Ni/ZrO 2 catalysts were investigated. Wherein, ZrO 2 support was further treated under H 2 , N 2 , and O 2 atmospheres respectively to obtain different oxygen species distribution over the surface, and 3 wt.% Ni was introduced by the deposition-precipitation method. The representative samples were characterized using XRD, EPR, XPS, FTIR, TPR, TPD , TPSR, TG, Raman and TPH techniques, etc. It was found that the treatment to ZrO 2 in the reducing gas such as H 2 was able to promote the formation of adsorbed oxygen species over the surface. CO 2 DRIFTS and CH 4 -TPSR experiments further confirmed that adsorbed oxygen species were favorable for enhancing both CO 2 adsorption and activation and CH 4 dissociation. As a result, the catalyst with more adsorbed oxygen species exhibited relatively outstanding performance for the DRM and promotional ability in removal of the deposited carbon.
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
CHINESE JOURNAL OF CATALYSIS
·
2022
·
IF 12.92
Zhaopeng Liu,Youming Ni,Zhongpan Hu,Yi Fu,Xudong Fang,Qike Jiang,Zhiyang Chen,Wenliang Zhu,Zhongmin Liu
The utilization of metal oxide-zeolite catalysts in the syngas-to-olefin reaction is a promising strategy for producing C 2 –C 4 olefins from non-petroleum resources. However, the effect of the crystal phase of metal oxides on the catalytic activity of these oxides is still ambiguous. Herein, typical metal oxides (ZnO/ZrO 2 ) with different crystal phases (monoclinic ( m -ZrO 2 ) and tetragonal ( t -ZrO 2 )) were employed for syngas conversion. The (ZnO/ m -ZrO 2 +SAPO-34) composite catalyst exhibited 80.5% selectivity for C 2 –C 4 olefins at a CO conversion of 27.9%, where the results are superior to those (CO conversion of 16.4% and C 2 –C 4 olefin selectivity of 76.1%) obtained over (ZnO/ t -ZrO 2 +SAPO-34). The distinct differences are ascribed to the larger number of hydroxyl groups, Lewis acid sites, and oxygen defects in ZnO/ m -ZrO 2 compared to ZnO/ t -ZrO 2 . These features result in the formation of more formate and methoxy intermediate species on the ZnO/ m -ZrO 2 oxides during syngas conversion, followed by the formation of more light olefins over SAPO-34. The present findings provide useful information for the design of highly efficient ZrO 2 -based catalysts for syngas conversion.
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
SEPARATION AND PURIFICATION TECHNOLOGY
·
2018
·
IF 3.927
Pan Gao,Yuan Song,Mengjie Hao,Anna Zhu,Hongwei Yang,Shaoxia Yang
A novel Fe 2 O 3 -ZrO 2 catalyst was prepared by the sol-gel method, and investigated for phenol degradation in the Fenton-like reaction under neutral pH condition. The ZrO 2 addition increased the surface areas of the catalyst. Scanning electron microscopy (SEM) showed that ZrO 2 nano-particle dispersed on the surface of Fe 2 O 3 . X-ray photoelectron spectroscopy (XPS) indicated that the Fe 2+ amount increased with the increase of the Zr content on the surface. The Fe 2 O 3 -ZrO 2 catalyst produced hydroxyl radicals (OH ) and superoxide radicals (O 2 − /HO 2 ), and exhibited good catalytic performance in the reaction. Total phenol conversion and 56% TOC removal were achieved after 210 min under neutral pH at 60 °C in the heterogeneous Fenton-like reaction. In addition, the prepared Fe 2 O 3 -ZrO 2 catalyst had good magnetism.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2021
·Vol. 13
·期 13
·3184-3197
·
IF 5.686
Chao Huang,Can Zhu,Mingwei Zhang,Yongwu Lu,Qianhao Wang,Heming Qian,Jiangang Chen,Kegong Fang
Graphical Synergetic effect : The physically mixed CuCoAl|t-ZrO 2 multifunctional catalyst could achieve superior selectivity towards alcohols while simultaneously inhibiting the generation of hydrocarbons from CO hydrogenation. Selective synthesis of higher alcohols from syngas is promising but remains challenging owing to the low stability and selectivity towards higher alcohols. Here we introduce a CuCoAl|t-ZrO 2 (t denotes tetragonal crystal phase) multifunctional catalyst that can achieve an alcohol selectivity of 64.8 % with 79.6 % C 2+ OH, and a total selectivity of alcohols and olefins to 81.7 %. The proper proximity was tuned to increase selectivity towards alcohols and decrease the selectivity towards hydrocarbons. The lower surface [H*]/[C*] ratio due to the stronger basic sites of the CuCoAl|t-ZrO 2 limited alkyl (CH x ) species hydrogenation, and promoted CO insertion and carbon chain growth, resulting in improving the alcohols selectivity. Meanwhile, the weaker adsorption of bridge-type adsorbed CO and the lower decomposition rate of multi-bonded adsorbed CO over CuCoAl|t-ZrO 2 inhibited hydrocarbon generation. The selective promotion of the reaction route via the synergetic effect between CuCoAl and t-ZrO 2 was proposed to boost higher alcohols selectivity. This work may aid the rational design of effective multifunctional catalyst with synergistic effects for tuning selectivity.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2023
·
IF 12.9
Nana Gong,Tao Zhang,Minghui Tan,Liyan Wang,Jiaqian Yang,Li Tan,Guohui Yang,Peng Wu,Yingquan Wu,Yisheng Tan
CO hydrogenation to isobutyl alcohol is a promising route for CO transformation to high value-added products. However, the formation mechanism of isobutyl alcohol is complex, and its synthesis requires complex catalysts and harsh reaction conditions, which hinders the identification of active sites. Herein, we efficiently synthesized isobutyl alcohol under mild conditions over a simple Cu–ZrO2 catalyst by decreasing the Cu loading. The space–time yield (STY) of isobutyl alcohol using an optimal CZ-0.11 catalyst was as high as 61.3 g·Lcat–1·h–1 with a CO conversion of 19.2%, far surpassing the STY of the state-of-the-art isobutyl alcohol synthesis (44.6 g·Lcat–1·h–1) under harsh conditions. Decreasing the Cu loading increased the distribution of smaller Cu particles and clarified the structure–activity relationship of Cu–Zr interactions for isobutyl alcohol synthesis. The enhanced Cu–Zr interaction led to the formation of more electron-deficient Cu species on the CZ-0.11 catalyst, which enriched the linearly adsorbed CO on Cu, as demonstrated by in situ diffuse reflectance infrared Fourier-transform spectroscopy. Experimental and theoretical results revealed that coupling of the bicarbonate species on ZrO2 with the linearly adsorbed CO species on electron-deficient Cu clusters promoted the formation of C2 intermediates and finally produced isobutyl alcohol through rapid β-addition. These insights into the active sites for CO hydrogenation to isobutyl alcohol may guide further catalyst designs.
研究领域:
催化化学
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能源化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子