Chemical Science
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2018
·Vol. 9
·期 14
·3426-3437
·
IF 9.063
Xinyu Li,Zhi-Jian Zhao,Liang Zeng,Jiubing Zhao,Hao Tian,Sai Chen,Kang Li,Sier Sang,Jinlong Gong
La2O3 exhibits good performance for various catalytic applications, such as oxidative coupling of methane (OCM) and dry reforming of methane (DRM), during which coke formation may lead to the deactivation of catalysts. Typically, the reaction between CO2 adsorbed on La2O3 and coke is the rate-determining step of the coke elimination process. This paper describes the influence of Ce addition on the CO2 adsorption and activation over La2O3. Combined with in situ and ex situ characterization and density functional theory (DFT) calculation, we show that Ce addition promotes the formation of bidentate carbonate on La2O3via tuning CO2 adsorption energy. In addition, Ce addition adjusts the ratio of bidentate/monodentate carbonate, and affects the ratio of hexagonal/monoclinic La2O2CO3 on the binary oxides. DRM is used as a probe reaction to examine the coke elimination performance of Ce–La binary oxide. It is found that when the Ce/La ratio reaches the optimal value (0.15), Ce–La binary oxide has the highest CO2 adsorption energy and predominantly promotes the formation of bidentate carbonate, and hence possesses the highest basicity above 700 °C and finally exhibits the best coke elimination performance.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2019
·
IF 4.084
Yinghui Sun,Guojie Zhang,Ying Xu,Riguang Zhang
The nitrogen doped activated carbon (AC-N) has been successfully prepared with commercial activated carbon as carbon material followed by a simple N-doping method using melamine as nitrogen sources. Using AC-N as the supports, cobalt supported on N-doped activated carbon (Co/AC-N) were developed and used as catalyst for dry reforming reaction (DRM). It was discovered that the Co/AC-N catalysts revealed much higher catalytic performance for DRM reaction in comparison to activated carbon supported cobalt catalyst (Co/AC). Moreover, the catalytic activity was influenced by preparation conditions of AC-N such as calcination temperature and the doping amount of nitrogen. The catalysts were characterized by BET, XRD , XPS , H 2 -TPR, Raman spectroscopy and TEM. It was found that catalytic activities of the catalysts with different calcination temperature and nitrogen doping were influenced by catalyst surface defects and disorders, Co 2+ /Co 3+ molar ratio , the content of nitrogen function groups (graphitic N, pyrrolic-N and pyridinic-N) and interaction between active metal and support. The Raman spectroscopy illustrated that the N-doped catalyst surface defects and disorders increased, which improved the performances of the Redox catalysts. The XPS valence band also revealed that higher Co 2+ /Co 3+ molar ratio and nitrogen function groups was achieved by decreasing calcination temperature and increasing nitrogen doping. In short, the doping of nitrogen increased the structural defects and the interaction between active metals and supports, modified the surface electronic structure, which were facilitated the oxidation and reduction of methane and carbon dioxide.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Chengming Huang,Yiming Zhang,Dingmei Han,Binbin He,Xinyu Sun,Meiyu Liu,Yi Mei,Yun Zu
Ni-based catalysts using siliceous materials as the supports have suffered from two challenging issues of sintering and carbon deposition for dry reforming of methane (DRM), resulted from a weak metal-support interaction. Given these, a novel metal–acid bifunctional Ni@S-1 zeolite catalyst is tailored from the evolution of hydroxylated nickel phyllosilicates that are formed by subtly controlling the coordination environments of Ni precursor complexes in the silicalite-1 (S-1) zeolite. The developed Ni 0.44 @S-1 catalyst renders almost equivalent CH 4 and CO 2 conversions (85.1 % and 88.7 %), high H 2 /CO molar ratio (about 1) and superb long-term stability during 100 h with no activity loss at 750 °C with a WHSV of 100 L·g cat −1 ·h −1 , outperforming other control catalysts under investigation. Such superior catalytic behavior benefits from the synergy between highly uniform Ni nanoparticles (3–5 nm) confined in the micropores of zeolite and substantially formed Lewis acid sites due to coordinatively unsaturated Ni 2+ sites located at the reduced 2:1 nickel phyllosilicate, as revealed by detailed characterizations. Meanwhile, it further discloses that a benign balance between formation and elimination of “process carbon” species is responsible for improving the carbon resistance of catalyst during the DRM reaction. The present design broadens a new insight for the development of new Ni-based catalysts with simultaneous coking- and sintering-resistant for the DRM application.
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
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Zengjian Cai,Yi Cai,Zhe Wang,Shoujie Liu,Xinhu Liang,Hao Ren,Yanan Cao,Zikang Su,Fengyi Shen,Shitu Yang,Guodong Sun,Xiaoxin Yang,Xueqiang Zhang,Mingzhen Hu,Xingwu Liu,Kebin Zhou
Selective conversion of CH 4 and CO 2 to syngas via the dry reforming reaction is highly desirable in terms of restraining the greenhouse effect and meanwhile acquiring useful chemicals. However, the most promising Ni catalysts for the reaction still suffer from severe coking and thus poor durability. Here, we report that using amorphous Ni nanoparticles synthesized on an N modified mesoporous silica support, the catalytic activity and coke-resistant performance of Ni toward the photothermal dry reforming of methane (DRM) are greatly improved. Theoretical calculations further unveil that the amorphous Ni nanoparticles are much more energetically favorable to activate the CH 4 and CO 2 molecules as well as to remove the C* intermediates for coke formation than their crystalline Ni counterparts, which renders the amorphous Ni nanoparticles with both superb activity and excellent coke-resisting property. This finding possibly provides a new avenue to make both highly efficient and anti-coking catalysts for the DRM reaction and beyond via facile amorphization of active metals.
研究领域:
化学工程
·
催化材料
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Jian-Feng Diao,Teng Zhang,Zhong-Ning Xu,Guo-Cong Guo
The plasma technology can effectively reduce the high temperature (≥700 °C) reaction condition of dry reforming of methane (DRM) reaction. But the inevitable carbon deposition problem seriously hinders the progress of plasma-involved DRM reaction. In order to promote the carbon elimination reaction between the adsorbed CO 2 and carbon deposition produced by CH 4 cracking, we have developed an effective atomic-level adjacent NiFe bimetallic catalyst. Compared to the Ni-based monometallic catalyst, the atomic-level adjacent NiFe bimetallic catalyst shows high activity and excellent stability in the plasma-involved DRM reaction. The conversions of CO 2 and CH 4 are 80.5% and 73.8%, respectively. Meanwhile, the catalytic performance remains well stable during the 100 h time-on-stream evaluation. The atomic-level adjacent NiFe bimetals were characterized by XRD, TEM and EXAFS et al., which are responsible for the improved activities. Most importantly, the addition of Fe can increase the surface oxygen and enhance CO 2 adsorption confirmed by XPS and CO 2 -TPD, which beneficial to improve the ability to convert carbon deposition and improve the stability of catalyst. This work provides a feasible synthetic strategy for designing the high activity and well stability catalyst for the plasma-involved DRM reaction.
研究领域:
催化化学
·
能源化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Xiaodi Zhang,Jiming Wang,Guojie Zhang,Jun Liu,Ying Wang,Yuqing Zhao,Guoqiang Li
To improve the DRM reaction performance of the catalysts, a series of Co–Ni/WC-AC catalysts are prepared by impregnation using WC-AC as the support. The structural features of the fresh and spent catalysts are characterized by BET, XRD , H 2 -TPR, XPS and TG . The results show that the introduction of Ni in the 20Co/WC-AC catalyst promotes the conversion of W species to WC. Further, WC enhances the interaction between the active metal and the support. Thus, the activity and sintering resistance of Co–Ni/WC-AC catalysts are improved. It is also found that the introduction of different ratios of Ni has a significant effect on the chemical environment (oxygen environment) on the catalyst surface.10Co–10Ni/WC-AC catalysts showed high surface O α and O β contents of 26% and 53%, respectively. The catalyst shows excellent catalytic performance. The conversion of CH 4 and CO 2 is stable at about 84% and 85% at 800 °C.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2024
·
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
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of CO2 Utilization
·
2019
·
IF 5.189
Qingxiang Ma,Yunxing Han,Qinhong Wei,Shengene Makpal,Xinhua Gao,Jianli Zhang,Tian-sheng Zhao
The bimodal mesoporous-macroporous alumina support was prepared via evaporation-induced self-assembly method (EISA), in which the polystyrene latex spheres with 100 nm diameter size were employed as sacrificial templates to fabricate macropores. The mesoporous-macroporous Al 2 O 3 -supported Ni catalyst (Ni/MM-A) was prepared by incipient-wetness impregnation method and applied for dry reforming of methane (DRM) to syngas. Characterizations by XRD, H 2 -TPR, SEM, and TEM revealed that the long-range ordered mesopore structure together with existing macropores was fabricated by using the EISA method, and the Ni particles were mainly stabilized inside the mesoporous channels of Al 2 O 3 support and the strong interaction between Ni and Al 2 O 3 was constructed. The Ni/MM-A catalyst exhibited more excellent catalytic performance in DRM reaction than that over Ni/M-A without macroporous structure. Stability tests for 100 h DRM reaction further indicated that the Ni/MM-A catalyst presented strong catalytic stability, which was significantly attributed to the macroporous structure that allowed the rapid mass transport, enhanced the tolerance to graphitic carbon and reduced the amount of graphitic carbon depositions.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2017
·
IF 4.601
Limo He,Song Hu,Long Jiang,Guang Liao,Liangping Zhang,Hengda Han,Xiaofang Chen,Yi Wang,Kai Xu,Sheng Su,Jun Xiang
Four types of biomass-derived organics (toluene/1-methylnaphthalene/phenol/ethanol) were catalytically decomposed and steam reformed over Ni/α-Al 2 O 3 for co-production of hydrogen and carbon nanotubes (CNTs). In the decomposition reaction, the oxygen functional group in phenol and ethanol promoted the co-production of hydrogen and CNTs, while a small amount of toluene and 1-methylnaphthalene were cracked to hydrogen and amorphous carbon. In the reforming reaction, the yields of hydrogen and CNTs sharply increased. More than 2000 mmol/(g-cata∗h) of H 2 and 260 mg/(g-cata∗h) of CNTs were produced after the reforming of toluene and ethanol. However, 1-methylnaphthalene was difficult to be reformed and small amount of CNTs were formed. The organics with low molecular weight and low degree of unsaturation conduced to the formation of hydrogen and CNTs. The growth of CNTs on Ni/α-Al 2 O 3 mainly follows the tip-growth mechanism. The diameter distribution of CNTs is not only influenced by Ni particle size, but also related to the different organics and steam addition.
研究领域:
能源化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2023
·
IF 7.3
Yuanjie Xu,Zemin An,Xin Yu,Jikang Yao,Qian Lv,Hua Yang,Zhengang Lv,Huichuang Guo,Qike Jiang,Wei Liu,Lizhi Wu,Li Tan,Yihu Dai,Yu Tang
Strong metal-support interaction (SMSI) is a crucial factor that determines the structure and performance of a supported metal catalyst. Herein, the SMSI effect of Rh nanoparticle catalyst supported on h-BN is investigated in the dry reforming of methane (DRM) reactions with different CO 2 /CH 4 ratios. The catalyst characterization results demonstrate that the SMSI effect allows the Rh nanoparticles to be encapsulated by BO x overlayers under DRM reaction conditions (CO 2 /CH 4 = 1/1), which prevents the interaction between the reactants and metal centers for causing rapid deactivation. By increasing the partial pressure of CO 2 (CO 2 /CH 4 = 3/1), Rh/BN exhibits significantly enhanced activity and long-term stability in the DRM reaction. CO 2 or H 2 O in the reactive atmosphere can effectively etch the BO x overlayers for steadily exposing the active Rh-BN interface sites, as evidenced by the characterization. This observation extends the understanding of the SMSI effect at the interfaces between metal and non-oxide support.
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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2013
·
IF 3.548
Zebao Rui,Danyan Feng,Huayao Chen,Hongbing Ji
Highly-ordered TiO 2 nanotube array (TiNT) was prepared by an electrochemical anodization method and used as the support for Ni and Ni–M (M = Ru, Pt and Rh) bimetallic catalysts . Ni/TiNT and Ni–M/TiNT were then applied to the combination reactions of the partial oxidation of methane reaction (POM) with the carbon dioxide reforming with methane reaction (CRM) for the syngas production . The results show that Ni/TiNT suffers from the formation of NiO and NiTiO 3 , and the coke deposition. The superior catalytic performance and the enhanced resistance ability against carbon formation are obtained over a small amount of noble metal modified Ni bimetallic catalysts, which are ranked as Ni/TiNT < Ni–Ru/TiNT < Ni–Pt/TiNT < Ni–Rh/TiNT. The interaction of Ni–M, i.e., enhanced reducibility of NiO and the maintenance of metallic Ni species even in the presence of oxygen, over Ni bimetallic catalysts is regarded as an important reason. Much short distance between the exothermic and the endothermic zones over Ni–M/TiNT catalysts bed can be realized, and a flat temperature profile in the catalyst bed is expected, which in turn can relieve the hot-spot and NiTiO 3 formation to some extent.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Ming Chen,Huan Liu,Ying Wang,Zhiyong Zhong,Yu Zeng,Yuxin Jin,Daiqi Ye,Limin Chen
TiO 2 , ZrO 2 and a series of TiO 2 -ZrO 2 (TxZ1, x means the atomic ratio of Ti/Zr = 10, 5, 1, 0.2 and 0.1) composite oxide supports were prepared through co-precipitation, and then 3 wt% Co was loaded through wetness impregnation methods. The obtained 3 wt% Co/TiO 2 (3CT), 3 wt% Co/ZrO 2 (3CZ) and 3 wt% Co/TxZ1 (3CTxZ1) catalysts were evaluated for the oxidative ethane dehydrogenation reaction with CO 2 (CO 2 -ODHE) as a soft oxidant. 3CT1Z1 catalyst exhibits excellent catalytic properties, with C 2 H 4 yield, C 2 H 6 conversion and CO 2 conversion about 24.5 %, 33.8 % and 18.0 % at 650 °C, respectively. X-Ray Diffraction (XRD), in-situ Raman, UV–vis diffuse reflectance spectra (UV–vis DRS), H 2 temperature-programmed reduction (H 2 -TPR), Electron paramagnetic resonance (EPR) and quasi in-situ X-ray Photoelectron Spectroscopy (XPS) have been utilized to thoroughly characterize the investigated catalysts. The results revealed that 3CT1Z1 produced TiZrO 4 solid solution with more metal defect sites and oxygen vacancies (Ov), promoting the formation of Co 2+ -TiZrO 4 structure. Furthermore, the presence of Ov and Ti 3+ can facilitate the high dispersion and stabilization of Co 2+ , as well as suppressing the severe reduction of Co 2+ , leading to superior ethane oxidative dehydrogenation activity. Besides, less Co 0 is beneficial to ODHE reaction, because of its promotion effects for reverse water gas shift reaction ; however, more Co 0 results in dry reforming reaction (DRE). This work will shed new lights for the design and preparation of highly efficient catalysts for ethylene production.
研究领域:
化学工程
·
催化
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子