The Experts below are selected from a list of 1737 Experts worldwide ranked by ideXlab platform
Bin Dai - One of the best experts on this subject based on the ideXlab platform.
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Effect of Phosphorus Ligand on Cu-Based Catalysts for Acetylene Hydrochlorination
ACS Sustainable Chemistry & Engineering, 2019Co-Authors: Wang Xuemei, Mingyuan Zhu, Bin DaiAbstract:Because of the toxicity of traditional mercury catalysts, nonmercuric catalysts for acetylene Hydrochlorination have been receiving great concern. In this study, a novel environmentally friendly Cu...
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Effect of Ru/Cl ratio on the reaction of acetylene Hydrochlorination
New Journal of Chemistry, 2017Co-Authors: Baochang Man, Bin Dai, Mingyuan Zhu, Haiyang Zhang, Chuanming Zhang, Hui Dai, Jinli ZhangAbstract:A series of catalysts with different ruthenium and chloride ratios were prepared and evaluated in the acetylene Hydrochlorination reaction, in combination with several characterization techniques. The results indicate that the catalyst with the optimum ratio of Ru/Cl = 5/7 exhibits the highest initial acetylene conversion above 96.1% at 180 °C, an GHSV(C2H2) of 180 h−1, and a feed ratio VHCl/VC2H2 of 1.15. Appropriate coordination numbers of ruthenium and chloride could increase the amount of ruthenium oxides, improve the dispersion of Ru species on the carrier and enhance the adsorption ability of the catalyst, consequently improving the catalytic performance. TPPB additives can further enhance the activity and stability of the catalyst, which also provides a promising strategy to explore highly efficient and economic mercury-free catalysts for the Hydrochlorination of acetylene.
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Cobalt-nitrogen-activated carbon as catalyst in acetylene Hydrochlorination
Catalysis Communications, 2017Co-Authors: Wenli Zhao, Mingyuan Zhu, Bin DaiAbstract:Abstract The development of new non-mercury based catalysts for the vinyl chloride industrial production has attracted recently the attention of many researchers. In spite of the good activity of Au-based supported catalysts reported so far, the high cost of gold impedes future use of such catalysts. In the present work, an environmentally friendly non-precious transition metal coordinated N-doped carbon material as a catalyst for acetylene Hydrochlorination reaction was developed, which shows good catalytic performance. The catalyst was characterized by Transmission Electron Microscopy coupled with Energy Dispersive X-ray analysis (TEM-EDX), X-ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). The obtained results indicated that Co-N-AC catalyst can significantly improve the adsorption of HCl. And XPS result demonstrated the presence of Co-N x , which plays a major role in acetylene Hydrochlorination reaction.
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The Preparation of Cu-g-C3N4/AC Catalyst for Acetylene Hydrochlorination
Catalysts, 2016Co-Authors: Wenli Zhao, Mingyuan Zhu, Bin DaiAbstract:A novel catalyst based on g-C3N4/activated carbon was prepared by adding CuCl2. The catalytic performance of the as-prepared catalyst was investigated in the acetylene Hydrochlorination reaction. X-ray photoelectron spectroscopy, temperature programmed desorption, low temperature N2 adsorption/desorption (Brunauer–Emmett–Teller), and thermal gravity analysis showed that Cu-g-C3N4/AC significantly enhanced the catalytic performance of the original catalyst by increasing the relative pyrrolic N content. Cu-g-C3N4/AC also affected the adsorption of hydrogen chloride and acetylene, as well as inhibited the coke deposition during acetylene Hydrochlorination.
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Catalyst-free Hydrochlorination protocol for terminal arylalkynes with hydrogen chloride
Chinese Chemical Letters, 2016Co-Authors: Furong Xiao, Hongwei Chen, Bin DaiAbstract:We present a simple and straightforward protocol for Hydrochlorination of terminal arylalkynes to vinyl chlorides using hydrogen chloride under mild reaction conditions. This protocol does not involve any metal catalysts or additives. It is simple, inexpensive, and easy to prepare, and exhibits good reaction activity. The Hydrochlorination proceeds smoothly to yield unique regioselective products via the Markovnikov addition rule.
Mingyuan Zhu - One of the best experts on this subject based on the ideXlab platform.
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Effect of Phosphorus Ligand on Cu-Based Catalysts for Acetylene Hydrochlorination
ACS Sustainable Chemistry & Engineering, 2019Co-Authors: Wang Xuemei, Mingyuan Zhu, Bin DaiAbstract:Because of the toxicity of traditional mercury catalysts, nonmercuric catalysts for acetylene Hydrochlorination have been receiving great concern. In this study, a novel environmentally friendly Cu...
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A novel S, N dual doped carbon catalyst for acetylene Hydrochlorination
Applied Catalysis A: General, 2018Co-Authors: Jian Wang, Lihua Kang, Fei Zhao, Chunli Zhang, Mingyuan ZhuAbstract:Abstract In this study, a sulphur and nitrogen dual-doped carbon catalyst was prepared via an easy route with p-phenyldiamine and (NH4)2S2O8 as the nitrogen and sulphur source, respectively. The obtained catalyst displayed efficient acetylene conversion for acetylene Hydrochlorination, and the presence of sulphur enhanced the catalytic activity of the nitrogen-doped carbon catalyst. These catalysts show that sulphur and nitrogen have a synergistic effect for acetylene Hydrochlorination. Furthermore, because of the addition of different sulphur contents, the pyrrolic N content causes certain changes in the catalysts, resulting in differences in the catalytic activity. Theoretical investigations reveal that the adsorption ability of C2H2 was enhanced by the doping of the S and N-doped carbon catalyst. This is an environmentally friendly catalyst with a broad development prospect and is cheap and easy to obtain.
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Effect of Ru/Cl ratio on the reaction of acetylene Hydrochlorination
New Journal of Chemistry, 2017Co-Authors: Baochang Man, Bin Dai, Mingyuan Zhu, Haiyang Zhang, Chuanming Zhang, Hui Dai, Jinli ZhangAbstract:A series of catalysts with different ruthenium and chloride ratios were prepared and evaluated in the acetylene Hydrochlorination reaction, in combination with several characterization techniques. The results indicate that the catalyst with the optimum ratio of Ru/Cl = 5/7 exhibits the highest initial acetylene conversion above 96.1% at 180 °C, an GHSV(C2H2) of 180 h−1, and a feed ratio VHCl/VC2H2 of 1.15. Appropriate coordination numbers of ruthenium and chloride could increase the amount of ruthenium oxides, improve the dispersion of Ru species on the carrier and enhance the adsorption ability of the catalyst, consequently improving the catalytic performance. TPPB additives can further enhance the activity and stability of the catalyst, which also provides a promising strategy to explore highly efficient and economic mercury-free catalysts for the Hydrochlorination of acetylene.
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Cobalt-nitrogen-activated carbon as catalyst in acetylene Hydrochlorination
Catalysis Communications, 2017Co-Authors: Wenli Zhao, Mingyuan Zhu, Bin DaiAbstract:Abstract The development of new non-mercury based catalysts for the vinyl chloride industrial production has attracted recently the attention of many researchers. In spite of the good activity of Au-based supported catalysts reported so far, the high cost of gold impedes future use of such catalysts. In the present work, an environmentally friendly non-precious transition metal coordinated N-doped carbon material as a catalyst for acetylene Hydrochlorination reaction was developed, which shows good catalytic performance. The catalyst was characterized by Transmission Electron Microscopy coupled with Energy Dispersive X-ray analysis (TEM-EDX), X-ray Diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS). The obtained results indicated that Co-N-AC catalyst can significantly improve the adsorption of HCl. And XPS result demonstrated the presence of Co-N x , which plays a major role in acetylene Hydrochlorination reaction.
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The Preparation of Cu-g-C3N4/AC Catalyst for Acetylene Hydrochlorination
Catalysts, 2016Co-Authors: Wenli Zhao, Mingyuan Zhu, Bin DaiAbstract:A novel catalyst based on g-C3N4/activated carbon was prepared by adding CuCl2. The catalytic performance of the as-prepared catalyst was investigated in the acetylene Hydrochlorination reaction. X-ray photoelectron spectroscopy, temperature programmed desorption, low temperature N2 adsorption/desorption (Brunauer–Emmett–Teller), and thermal gravity analysis showed that Cu-g-C3N4/AC significantly enhanced the catalytic performance of the original catalyst by increasing the relative pyrrolic N content. Cu-g-C3N4/AC also affected the adsorption of hydrogen chloride and acetylene, as well as inhibited the coke deposition during acetylene Hydrochlorination.
Jia Zhao - One of the best experts on this subject based on the ideXlab platform.
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Synergy between Ionic Liquids and CuCl2 in Gas–Liquid Phase Reactions of Acetylene Hydrochlorination
Catalysts, 2019Co-Authors: Yuxue Yue, Bolin Wang, Jia ZhaoAbstract:We studied the acetylene Hydrochlorination in gas–liquid phase reactions using ionic liquids (IL) as the reaction media and CuCl2 as the catalyst. The Cu-IL catalyst showed strong synergy between the IL and the Cu(II) active catalytic species. For [PrMIm]Cl, the Cu-IL catalyst exhibited significant enhancement of the catalytic activity in comparison with the CuCl2 catalyst supported on activated carbon and the IL alone as the catalyst. We have also performed DFT calculations of the reaction process, which provides a good explanation of our experimental results and for the synergetic effect. Our result suggests that ILs may be used to improve the activity of other metallic catalysts for the Hydrochlorination reaction of acetylene.
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towards a greener approach for the preparation of highly active gold carbon catalyst for the Hydrochlorination of ethyne
Journal of Catalysis, 2018Co-Authors: Jia Zhao, Yuanyuan Zhai, Bolin Wang, Yuxue Yue, Gangfeng Sheng, Huixia Lai, Yihan Zhu, Lingling GuoAbstract:Abstract Gold on activated carbon (Au/AC) materials are promising alternative catalysts for ethyne Hydrochlorination. The preparation of active, stable Au/AC catalysts without aqua regia for ethyne Hydrochlorination remains a significant challenge. A novel catalyst preparation protocol involving impregnation using a H 2 O 2 /HCl mixture is established for highly active Au/AC catalysts comprising primarily of single-site cationic Au species, as identified by systematic X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR) analyses and transmission electron microscopy (TEM) imaging. In addition, evaluation of the Au-C interface by temperature-programmed desorption (TPD) analyses showed that the oxidation of activated carbon by the H 2 O 2 /HCl mixture, which creates surface oxygen-containing functional groups (SOGs), is a crucial step for the formation of active Au/AC catalysts. The structure determination and comprehensive experimental evidence allow density functional theory (DFT) to predict that single-site cationic AuCl species stabilized by SOGs via -O- linkages are efficient active sites for Au-catalyzed ethyne Hydrochlorination. In addition, these catalysts can be reused for several times with negligible changes in performance after treatment with the H 2 O 2 /HCl mixture. The H 2 O 2 /HCl mixture is thus envisioned as a viable, green alternative to toxic aqua regia for the preparation of Au/AC catalysts for ethyne Hydrochlorination.
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Zeolite Supported Ionic Liquid Catalysts for the Hydrochlorination of Acetylene
Catalysts, 2018Co-Authors: Bolin Wang, Yuxue Yue, Gangfeng Sheng, Huixia Lai, Guo Lingling, Yaqin Deng, Jia ZhaoAbstract:An efficient and stable heterogeneous Zeolite Supported Ionic Liquid Catalyst (IL/CaX) has been explored in acetylene Hydrochlorination reaction. The IL/CaX catalyst exhibits excellent space time yields of vinyl chloride (VCM), when compared to the benchmark of Au/C systems. Through characterization and kinetic studies, the reaction follows a two-site mechanism, which is described as the adsorbed hydrogen chloride on the Ca2+ in zeolite, reacting with the adsorbed acetylene on the cation of ionic liquid to form vinyl chloride. The catalytic reaction takes place at the IL/CaX interface, whilst the upper interphase IL/CaX is not active. The deactivation of the catalyst is caused by the dissolving byproducts in the ionic liquid layer, which can be reactivated by a simple vacuum procedure. It is of great significance to study and develop green non-mercury catalysts, in acetylene Hydrochlorination.
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Carbon-supported perovskite-like CsCuCl3 nanoparticles: a highly active and cost-effective heterogeneous catalyst for the Hydrochlorination of acetylene to vinyl chloride
Catalysis Science & Technology, 2018Co-Authors: Yuanyuan Zhai, Jia Zhao, Bolin Wang, Yuxue Yue, Gangfeng Sheng, Huixia Lai, Guo Lingling, Hong WangAbstract:Non-mercuric catalysts in acetylene Hydrochlorination reaction have been gained much attention. Cu-based catalysts are low-cost, green and stable. However, their lower activity than that of mercury-based catalysts limits their practical applications. In this study, we report activated carbon-supported perovskite-like CsCuCl3 nanoparticles as a catalyst for Hydrochlorination of acetylene. Cu–Cs/AC with 1 wt% Cu content exhibits superior activity than pure Cu/AC and even Hg/AC. At the condition of 200 °C and 50 h−1 industrial space velocity, C2H2 conversion is maintained at 92% over 200 h. Our findings suggest that the low-cost Cu–Cs/AC catalyst can be envisioned as a viable alternative to commercial toxic HgCl2 for acetylene Hydrochlorination.
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Towards a greener approach for the preparation of highly active gold/carbon catalyst for the Hydrochlorination of ethyne
Journal of Catalysis, 2018Co-Authors: Jia Zhao, Yuanyuan Zhai, Bolin Wang, Yuxue Yue, Gangfeng Sheng, Huixia Lai, Yihan Zhu, Guo LinglingAbstract:Abstract Gold on activated carbon (Au/AC) materials are promising alternative catalysts for ethyne Hydrochlorination. The preparation of active, stable Au/AC catalysts without aqua regia for ethyne Hydrochlorination remains a significant challenge. A novel catalyst preparation protocol involving impregnation using a H 2 O 2 /HCl mixture is established for highly active Au/AC catalysts comprising primarily of single-site cationic Au species, as identified by systematic X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction (TPR) analyses and transmission electron microscopy (TEM) imaging. In addition, evaluation of the Au-C interface by temperature-programmed desorption (TPD) analyses showed that the oxidation of activated carbon by the H 2 O 2 /HCl mixture, which creates surface oxygen-containing functional groups (SOGs), is a crucial step for the formation of active Au/AC catalysts. The structure determination and comprehensive experimental evidence allow density functional theory (DFT) to predict that single-site cationic AuCl species stabilized by SOGs via -O- linkages are efficient active sites for Au-catalyzed ethyne Hydrochlorination. In addition, these catalysts can be reused for several times with negligible changes in performance after treatment with the H 2 O 2 /HCl mixture. The H 2 O 2 /HCl mixture is thus envisioned as a viable, green alternative to toxic aqua regia for the preparation of Au/AC catalysts for ethyne Hydrochlorination.
Jinli Zhang - One of the best experts on this subject based on the ideXlab platform.
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Characteristics of activated carbons modulate the catalytic performance for acetylene Hydrochlorination
Molecular Catalysis, 2020Co-Authors: Yawen Liu, Haiyang Zhang, Yanzhao Dong, Shuchun Zhao, Jinli ZhangAbstract:Abstract A number of commercial activated carbons (ACs) produced from different sources including pitch, coal, coconut and wood were evaluated as the catalyst for the Hydrochlorination reaction of acetylene. To disclose the structure-activity relationship, a series of characterizations were performed including texture, porosity, surface graphitization, conductivity, surface functional groups, surface adsorption properties and surface acidic sites distribution for these ACs. The results illustrate that the higher catalytic activity of ACs is attributed to higher conductivity, lower graphitization, less surface strong acidic sites and higher adsorption ability to reactants. This work would shed light on the rational design of carbon-based catalysts and their potential application in acetylene Hydrochlorination.
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Highly effective carbon-supported gold-ionic liquid catalyst for acetylene Hydrochlorination
RSC Advances, 2019Co-Authors: Weifeng Chen, Jinli ZhangAbstract:The sulfur-containing ionic liquid (IL) trimethylsulfonium iodide (C3H9SI) was used to synthesize an efficient non-mercuric catalyst with HAuCl4·4H2O as a precursor and spherical active carbon (SAC) as a support. Various Au-IL/SAC catalysts were synthesized using the incipient wetness impregnation technique and applied to acetylene Hydrochlorination. The 0.3% Au-IL/SAC catalyst showed the best catalytic performance, with an acetylene conversion of 90% at a temperature of 170 °C and gas hourly space velocity (GHSV) of 360 h−1 using water as the solvent. The catalyst also displayed excellent long-term stability: C2H2 conversion was maintained at 97% for up to 200 h (T = 170 °C, GHSV = 90 h−1). Brunauer–Emmett–Teller surface area, thermogravimetric analysis, temperature programmed desorption, X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy results together showed that the C3H9SI additive significantly improved the dispersion of Au species and inhibited coke deposition on the catalyst surface during the acetylene Hydrochlorination reaction. The superior activity and stability of the Au-IL/SAC catalyst make it a green catalyst for the industrial application of acetylene Hydrochlorination.
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Molecular design of ionic liquids as novel non-metal catalysts for the acetylene Hydrochlorination reaction.
Physical chemistry chemical physics : PCCP, 2019Co-Authors: Yao Nian, Jinli Zhang, Yan Wang, Pewee Datoo Kolubah, You HanAbstract:Theoretical prediction of catalytic performance is crucial for the rational design of novel catalysts. In this study, density functional theory (DFT) simulations were carried out to predict the catalytic performance of four ionic liquids (ILs) used as novel non-metal catalysts in the acetylene Hydrochlorination reaction, and the obtained catalytic performances were verified via our experimental tests; moreover, both the theoretical and experimental results showed that the catalytic performance of the four IL catalysts followed the order tetraphenylphosphonium bromide (TPPB) > tetraphenylphosphonium chloride (TPPC) > butyltriphenylphosphonium bromide (BuTPPB) ≫ tetraphenylphosphonium tetrafluoroborate (TPPT), and the 15%TPPB/SAC catalyst exhibited efficient catalytic performance when compared with the recently reported non-metal catalysts for the acetylene Hydrochlorination reaction. Furthermore, the catalytic mechanisms of the four ILs with different cations and anions were revealed via theoretical Mulliken, partial density of states (PDOS) and electron density difference (EDD) analyses combined with the experimental XPS and XRD characterizations. The results showed that the effects of the anions on the catalytic activity were much significant than those of the cations. A good IL non-metal catalyst for acetylene Hydrochlorination would mainly donate electrons to Cl to activate the H–Cl bond, and then, the electrons would be donated back to the IL catalyst in the transition state. This study provides new insights into the design of efficient nonmercuric catalysts for the acetylene Hydrochlorination reaction.
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Highly Efficient Ru@IL/AC To Substitute Mercuric Catalyst for Acetylene Hydrochlorination
2017Co-Authors: Shanshan Shang, Jinli Zhang, Yan Wang, Wei Zhao, You HanAbstract:We synthesized a series of Ru@IL/AC catalysts using the incipient wetness impregnation technique associated with five kinds of ionic liquids, aiming to explore an efficient nonmercuric catalyst for the acetylene Hydrochlorination reaction. Over the optimal 1%Ru@15%TPPB/AC catalyst, the acetylene conversion was maintained at 99.7% at 48 h (T = 170 °C, GHSVC2H2 = 360 h–1, and VHCl/VC2H2 = 1.15). Additionally, with lower Ru loading (0.2%Ru@15%TPPB/AC), the acetylene conversion still remained at 99.3% within 400 h. Characterized by CO pulse chemisorption, TEM, XPS, TGA, among other methods, it is indicated that TPPB IL could effectively improve the dispersion of Ru species, suppress the reduction of active Ru species, and inhibit the coke deposition during the acetylene Hydrochlorination reaction. The interactive mechanism between TPPB and the reactants and the product was investigated to disclose the effect of TPPB IL on the catalytic performance of Ru-based catalyst, in combination with DFT calculations. The enhanced activity and long-term stability of Ru@IL/AC suggest the promising industrial application as the nonmercuric catalyst for acetylene Hydrochlorination
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Effect of Ru/Cl ratio on the reaction of acetylene Hydrochlorination
New Journal of Chemistry, 2017Co-Authors: Baochang Man, Bin Dai, Mingyuan Zhu, Haiyang Zhang, Chuanming Zhang, Hui Dai, Jinli ZhangAbstract:A series of catalysts with different ruthenium and chloride ratios were prepared and evaluated in the acetylene Hydrochlorination reaction, in combination with several characterization techniques. The results indicate that the catalyst with the optimum ratio of Ru/Cl = 5/7 exhibits the highest initial acetylene conversion above 96.1% at 180 °C, an GHSV(C2H2) of 180 h−1, and a feed ratio VHCl/VC2H2 of 1.15. Appropriate coordination numbers of ruthenium and chloride could increase the amount of ruthenium oxides, improve the dispersion of Ru species on the carrier and enhance the adsorption ability of the catalyst, consequently improving the catalytic performance. TPPB additives can further enhance the activity and stability of the catalyst, which also provides a promising strategy to explore highly efficient and economic mercury-free catalysts for the Hydrochlorination of acetylene.
Tongtong Zhang - One of the best experts on this subject based on the ideXlab platform.
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One-pot synthesis of nitrogen and sulfur co-doped activated carbon supported AuCl3 as efficient catalysts for acetylene Hydrochlorination
Chinese Chemical Letters, 2016Co-Authors: Jia Zhao, Tongtong ZhangAbstract:Abstract Commercialization of acetylene Hydrochlorination using AuCl3 catalysts has been impeded by its poor stability. We have been studying that nitrogen-modified Au/NAC catalyst delivered a stable performance which can improve acetylene Hydrochlorination activity and has resistance to catalytic deactivation. Here we show that nitrogen and sulfur co-doped activated carbon supported AuCl3 catalyst worked as efficient catalysts for the Hydrochlorination of acetylene to vinyl chloride. Au/NSAC catalyst demonstrated high activity comparative to Au/AC catalyst. Furthermore, it also delivered stable performance within the selectivity of acetylene, reaching more than 99.5%, and there was only a 3.3% C2H2 conversion loss after running for 12 h under the reaction conditions of a temperature of 180 °C and a C2H2 hourly space velocity of 1480 h−1. The presence of the sulfur atoms may serve to immobilize/anchor the Au and also help prevent reduction and sintering of the Au and hence improve the catalytic activity and stability. The excellent catalytic performance of the Au/NSAC catalyst demonstrated its potential as an alternative to mercury chloride catalysts for acetylene Hydrochlorination.
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Improvement of the stability of Hg/AC catalysts by CsCl for the high-temperature Hydrochlorination of acetylene
Chinese Chemical Letters, 2016Co-Authors: Jia Zhao, Tongtong ZhangAbstract:Activated carbon-supported mercuric chloride (HgCl2) is used as an industrial catalyst for acetylene Hydrochlorination. However, the characteristic of easy sublimation of HgCl2 leads to the deactivation of the catalyst. Here, we showed that the thermal stability of the Hg/AC catalyst can be evidently improved when CsCl is added into the Hg/AC catalyst. Compared with the pure Hg/AC catalyst, the sublimation rate of HgCl2 from the Hg–Cs/AC catalyst decreased significantly and the Hg–Cs/AC catalyst showed better catalytic activity and stability in the reaction. This promoting effect is related to the existence of cesium mercuric chlorides (CsxHgyClx+2y) highlighted by XRD, HR-TEM and EDX analyses. Thus, reacting HgCl2 with alkali chlorides to form alkali-mercuric chlorides may be a key to design highly efficient and thermally stable mercuric chloride catalyst for Hydrochlorination reactions.
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activated carbon supported ternary gold cesium i indium iii catalyst for the Hydrochlorination of acetylene
Catalysis Science & Technology, 2015Co-Authors: Jia Zhao, Tongtong Zhang, Qunfeng Zhang, N I JunAbstract:Commercialization of acetylene Hydrochlorination using AuCl3 catalysts has been impeded by its poor stability. We have been studying CsCl as a promoter, which can improve acetylene Hydrochlorination activity and has resistance to catalytic deactivation. InIII added to the Au–CsI/AC catalysts worked as efficient catalysts for the Hydrochlorination of acetylene to vinyl chloride. A series of trimetallic catalysts (1AuxInIII4CsI/AC with x = 0.5, 1, 2, 3) were prepared and assessed for their ability to promote Hydrochlorination of acetylene. The enhancement of stability observed for a Au/InIII/CsI weight ratio of 1:1:4 was particularly remarkable. It delivered stable performance within the conversion of acetylene, reaching more than 92.8%, and there was only 3.7% C2H2 conversion loss after running for 50 h under the reaction conditions of a temperature of 180 °C and a C2H2 hourly space velocity of 1480 h−1. Moreover, the 1Au1InIII4CsI/AC catalyst delivered stable performance with an estimated lifetime exceeding 6520 h at a C2H2 hourly space velocity of 50 h−1. H2-TPR, TEM, HCl-TPD, C2H2-TPD, XPS and TGA techniques were further applied to reveal the structural information on the Au–InIII–CsI/AC catalysts. The results reveal that the addition of InCl3 increased the electron density of Au3+ species via electron transfer from the In atoms to the Au3+ center which can increase the adsorption of hydrogen chloride and therefore improve the catalytic stability. These results demonstrate that the addition of metal additives CsCl and InCl3 results in a synergistic effect to enhance the activity and the stability of Au-based catalysts. The excellent catalytic performance of the 1Au1InIII4CsI/AC catalyst demonstrated its potential as an alternative to mercury chloride catalysts for acetylene Hydrochlorination.
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enhancement of au ac acetylene Hydrochlorination catalyst activity and stability via nitrogen modified activated carbon support
Chemical Engineering Journal, 2015Co-Authors: Jia Zhao, Tongtong ZhangAbstract:Abstract Improving the durability of Au 3+ catalyst is an important step in increasing its utility when performing catalyzed acetylene Hydrochlorination. Using nitrogen-modified activated carbon (NAC) as support, Au/NAC1 catalyst demonstrated excellent activity and stability when compared with the undoped Au/AC1 under the conditions of 180 °C and 1480 h −1 of gas hourly space velocity (C 2 H 2 based). Moreover, the Au/NAC1 catalyst delivered a stable performance during a 300 h test with the conversion of acetylene and the selectivity of vinyl chloride both reaching more than 99.9% at C 2 H 2 hourly space velocity 100 h −1 , which substantially exceeds the best results reported in previous literature. The removal of carboxylic groups from the activated carbon surface and the introduction of nitrogen atoms as anchor sites by thermal pretreatment with urea are preferential to stabilize the catalytic active Au 3+ species and inhibit the reduction of Au 3+ to Au 0 in the preparation process of Au/NAC1 catalysts. In addition, increasing the electron density of Au 3+ via electron transfer from nitrogen atoms to the Au 3+ center can increase the adsorption of hydrogen chloride and inhibit the reduction of Au 3+ to Au 0 during acetylene Hydrochlorination and hence improve the catalytic stability. The excellent catalytic performance of the Au/NAC1 catalyst demonstrated its potential as an alternative to mercury chloride catalysts for acetylene Hydrochlorination.
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Activated carbon supported ternary gold–cesium(I)–indium(III) catalyst for the Hydrochlorination of acetylene
Catalysis Science & Technology, 2015Co-Authors: Jia Zhao, Tongtong Zhang, Qunfeng ZhangAbstract:Commercialization of acetylene Hydrochlorination using AuCl3 catalysts has been impeded by its poor stability. We have been studying CsCl as a promoter, which can improve acetylene Hydrochlorination activity and has resistance to catalytic deactivation. InIII added to the Au–CsI/AC catalysts worked as efficient catalysts for the Hydrochlorination of acetylene to vinyl chloride. A series of trimetallic catalysts (1AuxInIII4CsI/AC with x = 0.5, 1, 2, 3) were prepared and assessed for their ability to promote Hydrochlorination of acetylene. The enhancement of stability observed for a Au/InIII/CsI weight ratio of 1:1:4 was particularly remarkable. It delivered stable performance within the conversion of acetylene, reaching more than 92.8%, and there was only 3.7% C2H2 conversion loss after running for 50 h under the reaction conditions of a temperature of 180 °C and a C2H2 hourly space velocity of 1480 h−1. Moreover, the 1Au1InIII4CsI/AC catalyst delivered stable performance with an estimated lifetime exceeding 6520 h at a C2H2 hourly space velocity of 50 h−1. H2-TPR, TEM, HCl-TPD, C2H2-TPD, XPS and TGA techniques were further applied to reveal the structural information on the Au–InIII–CsI/AC catalysts. The results reveal that the addition of InCl3 increased the electron density of Au3+ species via electron transfer from the In atoms to the Au3+ center which can increase the adsorption of hydrogen chloride and therefore improve the catalytic stability. These results demonstrate that the addition of metal additives CsCl and InCl3 results in a synergistic effect to enhance the activity and the stability of Au-based catalysts. The excellent catalytic performance of the 1Au1InIII4CsI/AC catalyst demonstrated its potential as an alternative to mercury chloride catalysts for acetylene Hydrochlorination.