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Highly reactive and reusable heterogeneous activated carbons-based palladium catalysts for Suzuki-Miyaura reaction
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作者 Yifan Jiang Bingqi Xie Jisong Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第8期165-172,共8页
Suzuki-Miyaura reaction of aryl halides with phenylboronic acid using a heterogeneous palladium catalyst based on activated carbons(AC) was systematically investigated in this work. Two different reaction modes(batch ... Suzuki-Miyaura reaction of aryl halides with phenylboronic acid using a heterogeneous palladium catalyst based on activated carbons(AC) was systematically investigated in this work. Two different reaction modes(batch procedure and continuous-flow procedure) were used to study the variations of reaction processing. The heterogeneous catalysts presented excellent reactivity and recyclability for iodobenzene and bromobenzene substrates in batch mode, which can be attributed to stabilization of Pd nanoparticles by the thiol and amino groups on the AC supports. However, significant dehalogenation in the reaction mixture and Pd leaching from the heterogeneous catalysts were observed in continuous-flow mode.This unique phenomenon in continuous-flow mode resulted in a dramatic decline in reaction selectivity and durability of heterogeneous catalysts comparing with that of batch mode. In addition, the heterogeneous Pd catalysts with thiol-and amino-modified AC supports exhibited different reactivity and durability in batch and continuous-flow mode owing to the difference of interaction between Pd species and AC supports. 展开更多
关键词 Suzuki-Miyaura reaction Heterogeneous palladium catalysts activated carbon Thiol-and amino-functionalization catalyst support Packed bed
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Systematic variation of the sodium/sulfur promoter content on carbon-supported iron catalysts for the Fischer–Tropsch to olefins reaction 被引量:3
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作者 Martin Oschatz Nynke Krans +1 位作者 Jingxiu Xie Krijn P.de Jong 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第6期985-993,共9页
The Fischer–Tropsch to olefins(FTO) process is a method for the direct conversion of synthesis gas to lower C–Colefins. Carbon-supported iron carbide nanoparticles are attractive catalysts for this reaction.The ca... The Fischer–Tropsch to olefins(FTO) process is a method for the direct conversion of synthesis gas to lower C–Colefins. Carbon-supported iron carbide nanoparticles are attractive catalysts for this reaction.The catalytic activity can be improved and undesired formation of alkanes can be suppressed by the addition of sodium and sulfur as promoters but the influence of their content and ratio remains poorly understood and the promoted catalysts often suffer from rapid deactivation due to particle growth. A series of carbon black-supported iron catalysts with similar iron content and nominal sodium/sulfur loadings of 1–30/0.5–5 wt% with respect to iron are prepared and characterized under FTO conditions at 1and 10 bar syngas pressure to illuminate the influence of the promoter level on the catalytic properties.Iron particles and promoters undergo significant reorganization during FTO operation under industrially relevant conditions. Low sodium content(1–3 wt%) leads to a delay in iron carbide formation. Sodium contents of 15–30 wt% lead to rapid loss of catalytic activity due to the covering of the iron surface with promoters during particle growth under FTO operation. Higher activity and slower loss of activity are observed at low promoter contents(1–3 wt% sodium and 0.5–1 wt% sulfur) but a minimum amount of alkali is required to effectively suppress methane and C–Cparaffin formation. A reference catalyst support(carbide-derived carbon aerogel) shows that the optimum promoter level depends on iron particle size and support pore structure. 展开更多
关键词 Fischer–Tropsch to olefins synthesis C2–C4 olefins iron catalysts Promoters carbon supports
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Effect of Activated Carbon as a Support on Metal Dispersion and Activity ofRuthenium Catalyst for Ammonia Synthesis 被引量:3
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作者 ZHENG Xiao-ling ZHANG Shu-juan +3 位作者 LIN Jian-xin XU Jiao-xing FU Wu-jun WEI Ke-mei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第4期448-452,共5页
Ten kinds of activated carbon from different raw materials were used as supports to prepare ruthenium catalysts. N_2 physisorption and CO chemisorption were carried out to investigate the pore size distribution and th... Ten kinds of activated carbon from different raw materials were used as supports to prepare ruthenium catalysts. N_2 physisorption and CO chemisorption were carried out to investigate the pore size distribution and the ruthenium dispersion of the catalysts. It was found that the Ru dispersion of the catalyst was closely related to not only the texture of carbon support but also the purity of activated carbon. The activities of a series of the carbon-supported barium-promoted Ru catalysts for ammonia synthesis were measured at 425 ℃, 10 0 MPa and 10 000 h -1. The result shows that the same raw material activated carbon, with a high purity, high surface area, large pore volume and reasonable pore size distribution might disperse ruthenium and promoter sufficiently, which activated carbon as support, could be used to manufacture ruthenium catalyst with a high activity for ammonia synthesis. The different raw material activated carbon as the support would greatly influence the catalytic properties of the ruthenium catalyst for ammonia synthesis. For example, with coconut shell carbon(AC1) as the support, the ammonia concentration in the effluent was 13 17% over 4%Ru-BaO/AC1 catalyst, while with the desulfurized coal carbon(AC10) as the support, that in the effluent was only 1 37% over 4%Ru-BaO/AC10 catalyst. 展开更多
关键词 activated carbon RUTHENIUM supported catalyst Ammonia synthesis
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Recent advances in application of iron‐based catalysts for CO_(x) hydrogenation to value‐added hydrocarbons 被引量:3
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作者 Junhui Liu Yakun Song +2 位作者 Xuming Guo Chunshan Song Xinwen Guo 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第3期731-754,共24页
The widespread utilization of fossil fuels has caused an associated increase in CO_(2) emissions over the past few decades,which has resulted in global warming and ocean acidification.CO hydrogenation(Fischer‐Tropsch... The widespread utilization of fossil fuels has caused an associated increase in CO_(2) emissions over the past few decades,which has resulted in global warming and ocean acidification.CO hydrogenation(Fischer‐Tropsch synthesis,FTS)is considered a significant route for the production of liquid fuels and chemicals from nonpetroleum sources to meet worldwide demand.Conversion of CO_(2) with renewable H_(2) into valuable hydrocarbons is beneficial for reducing dependence on fossil fuels and mitigating the negative effects of high CO_(2) concentrations in the atmosphere.Iron‐based catalysts exhibit superior catalytic performance in both FTS and CO_(2) hydrogenation to value‐added hydrocarbons.The abundance and low cost of iron‐based catalysts also promote their wide application in CO_(x) hydrogenation.This paper provides a comprehensive overview of the significant developments in the application of iron‐based catalysts in these two fields.The active phases,promoter effect,and support of iron‐based catalysts are discussed in the present paper.Based on understanding of these three essential aspects,we also cover recent advances in the design and preparation of novel iron‐based catalysts for FTS and CO_(2) hydrogenation.Current challenges and future catalytic applications are also outlined. 展开更多
关键词 iron‐based catalyst Fischer‐Tropsch synthesis CO_(2)hydrogenation PROMOTER Support Active phase
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Effects of the Different Supports on the Activity and Selectivity of Iron-Cobalt Bimetallic Catalyst for Fischer-Tropsch Synthesis 被引量:3
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作者 Xiangdong Ma Qiwen Sun +2 位作者 Fahai Cao Weiyong Ying Dingye Fang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2006年第4期335-339,共5页
Silica, alumina, and activated carbon supported iron-cobalt catalysts were prepared by incipient wetness impregnation. These catalysts have been characterized by BET, X-ray diffraction (XRD), and temperature-program... Silica, alumina, and activated carbon supported iron-cobalt catalysts were prepared by incipient wetness impregnation. These catalysts have been characterized by BET, X-ray diffraction (XRD), and temperature-programmed reduction (TPR). Activity and selectivity of iron-cobalt supported on different carriers for CO hydrogenation were studied under the conditions of 1.5 MPa, 493 K, 630 h^-1, and H2/CO ratio of 1.6. The results indicate that the activity, C4 olefin/(C4 olefin+C4 paraffin) ratio, and C5 olefin/(C5 olefin+C5 paraffin) decrease in the order of Fe-Co/SiO2, Fe-Co/AC1, Fe-Co/Al2O3 and Fe- Co/AC2. The activity of Fe-Co/SiO2 reached a maximum. The results of TPR show that the Fe-Co/SiO2 catalyst is to some extent different. XRD patterns show that the Fe-Co/SiO2 catalyst differs significantly from the others; it has two diffraction peaks. The active spinel phase is correlated with the supports. 展开更多
关键词 Fischer-Tropsch synthesis bimetallic catalyst iron COBALT support silica ALUMINA active carbon SYNGAS
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Effects of Reaction Conditions on Performance of Ru Catalyst and Iron Catalyst for Ammonia Synthesis 被引量:2
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作者 潘崇根 李瑛 +1 位作者 蒋文 刘化章 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第2期273-277,共5页
Activated carbon-supported Ru-based catalyst and A301 iron catalyst were prepared,and the influences of reaction temperature,space velocity,pressure,and H2/N2 ratio on performance of iron catalyst coupled with Ru cata... Activated carbon-supported Ru-based catalyst and A301 iron catalyst were prepared,and the influences of reaction temperature,space velocity,pressure,and H2/N2 ratio on performance of iron catalyst coupled with Ru catalyst in series for ammonia synthesis were investigated.The activity tests were also performed on the single Ru and Fe catalysts as comparison.Results showed that the activity of the Ru catalyst for ammonia synthesis was higher than that of the iron catalyst by 33.5%-37.6% under the reaction conditions:375-400 °C,10 MPa,10000 h-1,H2︰N2 3,and the Ru catalyst also had better thermal stability when treated at 475 °C for 20 h.The outlet ammonia concentration using Fe-Ru catalyst was increased by 45.6%-63.5% than that of the single-iron catalyst at low tem-perature (375-400 °C),and the outlet ammonia concentration increased with increasing Ru catalyst loading. 展开更多
关键词 Ru catalyst iron catalyst ammonia synthesis active carbon reactors in series
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Strengthening decomposition of oxytetracycline in DBD plasma coupling with Fe-Mn oxide-loaded granular activated carbon 被引量:1
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作者 Shoufeng TANG Xue LI +3 位作者 Chen ZHANG Yang LIU Weitao ZHANG Deling YUAN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第2期90-96,共7页
A catalytic approach using a synthesized iron and manganese oxide-supported granular activated carbon(Fe-Mn GAC) under a dielectric barrier discharge(DBD) plasma was investigated to enhance the degradation of oxytetra... A catalytic approach using a synthesized iron and manganese oxide-supported granular activated carbon(Fe-Mn GAC) under a dielectric barrier discharge(DBD) plasma was investigated to enhance the degradation of oxytetracycline(OTC) in water. The prepared Fe-Mn GAC was characterized by x-ray diffraction and scanning electron microscopy, and the results showed that the bimetallic oxides had been successfully spread on the GAC surface. The experimental results showed that the DBD?+?Fe-Mn GAC exhibited better OTC removal efficiency than the sole DBD and DBD?+?virgin GAC systems. Increasing the fabricated catalyst and discharge voltage was favorable to the antibiotic elimination and energy yield in the hybrid process. The coupling process could be elucidated by the ozone decomposition after Fe-Mn GAC addition, and highly hydroxyl and superoxide radicals both play significant roles in the decontamination. The main intermediate products were identified by HPLC-MS to study the mechanism in the collaborative system. 展开更多
关键词 dielectric barrier discharge plasma iron and MANGANESE OXIDES OXYTETRACYCLINE DECOMPOSITION supported GRANULAR activated carbon
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Synthesis of Polyketone by Copolymerization of Styrene and CO Using Carbon Nanotube-Complex Pd^(2+) Catalyst 被引量:1
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作者 郭锦棠 肖淼 +1 位作者 王海霞 胡光 《Transactions of Tianjin University》 EI CAS 2014年第2期86-90,共5页
The dipping method was devised to deposit Pd onto carbon nanotube as supported catalyst(Pd/CNT) for the copolymerization of carbon monoxide(CO) and styrene(ST) towards the formation of polyketone(PK).The Pd/CNT was ch... The dipping method was devised to deposit Pd onto carbon nanotube as supported catalyst(Pd/CNT) for the copolymerization of carbon monoxide(CO) and styrene(ST) towards the formation of polyketone(PK).The Pd/CNT was characterized by X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD) and high-resolution transmission electron microscopy(HRTEM).The construction and crystallization property of PK were evaluated by Fourier transform infrared spectroscopy(FTIR),13C-nuclear magnetic resonance(NMR) and XRD,respectively.The catalyst showed excellent activity and reusability in promoting the fabrication of PK.It can be recycled 14 times with the highest total catalytic activity of 4 239.64 gPK/(gPd·h) at Pd content of 8.63wt%.The results indicate that the prepared catalyst is effective to catalyze the copolymerization of CO and styrene. 展开更多
关键词 carbon nanotube supported catalyst catalytic activity COPOLYMERIZATION POLYKETONE
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碳负载Cs和Cu基催化剂用于1,1,2-三氯乙烷的气相脱氯化氢
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作者 盖星宇 岳玉学 +5 位作者 杨春华 张子龙 蔡天姿 张海丰 王柏林 李小年 《化工学报》 EI CSCD 北大核心 2024年第2期575-583,共9页
采用浸渍法制备了Cs/AC和Cu/AC催化剂,并在1,1,2-三氯乙烷的气相脱氯化氢反应中进行了评价。在浸渍过程中,活性炭表面产生高度分散的Cs物种和少量结晶的Cu物种。Cs/AC催化剂具有优异的催化性能,在573 K、1000 h^(−1)的反应条件下,转化... 采用浸渍法制备了Cs/AC和Cu/AC催化剂,并在1,1,2-三氯乙烷的气相脱氯化氢反应中进行了评价。在浸渍过程中,活性炭表面产生高度分散的Cs物种和少量结晶的Cu物种。Cs/AC催化剂具有优异的催化性能,在573 K、1000 h^(−1)的反应条件下,转化率稳定在86.7%。实验和理论计算表明,CsCl物种促进了1,1,2-三氯乙烷的吸附和活化,从而提高了原料转化率。这项工作为探索高效经济地合成偏二氯乙烯提供了一种很有前景的策略。 展开更多
关键词 偏二氯乙烯 活性炭 催化 1 1 2-三氯乙烷脱氯化氢 催化剂载体
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碳球负载纳米零价铁活化过硫酸盐降解水中恩诺沙星的性能研究
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作者 赵乐依 朱雪强 +1 位作者 刘健 路平 《生态环境学报》 CSCD 北大核心 2024年第5期757-770,共14页
恩诺沙星(ENR)属于氟喹诺酮类抗生素,具有稳定性强、难分解、易富集等特性,常用于水产养殖、畜禽养殖等,其在环境中总体浓度较低,但长期低剂量暴露可能对人体健康和生态环境带来极大风险。采用碳球(CS)负载纳米零价铁(nZVI)活化过硫酸盐... 恩诺沙星(ENR)属于氟喹诺酮类抗生素,具有稳定性强、难分解、易富集等特性,常用于水产养殖、畜禽养殖等,其在环境中总体浓度较低,但长期低剂量暴露可能对人体健康和生态环境带来极大风险。采用碳球(CS)负载纳米零价铁(nZVI)活化过硫酸盐(PS)去除水体中的ENR。应用两步碳热还原法制备了碳球负载纳米零价铁(Fe@C),采用单因素实验研究了Fe@C投加量、PS浓度、ENR初始浓度和pH值对ENR降解的影响及降解动力学,通过自由基及降解产物分析推测了Fe@C活化PS降解ENR的反应机制与降解路径。结果表明,ENR的降解符合准一级动力学,在温度为25℃、Fe@C投加量为0.3 g∙L^(-1)、PS浓度为1 mmol∙L^(-1)、ENR初始质量浓度为10 mg∙L^(-1)、pH值为3的条件下,ENR降解率最高达98.6%。ENR降解率随着腐植酸(HA)、氨氮(NH3-N)、碳酸氢根离子(HCO3-)浓度的升高而降低。氯离子(Cl-)在低浓度时对ENR的降解有微弱的促进作用,高浓度时有抑制作用。自由基淬灭实验表明SO4-∙是ENR降解的主要自由基。根据ENR的降解产物,推测哌嗪环的裂解、喹诺酮环的分解及脱氟为ENR主要降解途径。碳球负载纳米零价铁活化PS高级氧化工艺可作为一种高效去除水中ENR的工艺。 展开更多
关键词 恩诺沙星 碳球负载纳米零价铁 过硫酸盐 降解途径 活化 降解动力学
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CeO_(2)载体在CO_(2)加氢制甲醇中的应用和研究进展
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作者 周运桃 王洪星 +1 位作者 李新刚 崔丽凤 《化工进展》 EI CAS CSCD 北大核心 2024年第5期2723-2738,共16页
随着经济的快速发展,CO_(2)排放导致的温室效应日益严峻,通过与绿氢反应将其转化为甲醇等有价值的化工产品是减少CO_(2)排放、缓解全球气候变暖的有效途径。近年来,CeO_(2)负载金属催化剂在CO_(2)加氢制甲醇反应中得到了广泛关注。本文... 随着经济的快速发展,CO_(2)排放导致的温室效应日益严峻,通过与绿氢反应将其转化为甲醇等有价值的化工产品是减少CO_(2)排放、缓解全球气候变暖的有效途径。近年来,CeO_(2)负载金属催化剂在CO_(2)加氢制甲醇反应中得到了广泛关注。本文主要综述了CeO_(2)表面氧空位和碱性位点、Ce3+/Ce4+可逆氧化还原能力、几何形貌等特性在CO_(2)/H_(2)吸附活化和甲醇形成过程中所起到的重要作用,比较了CeO_(2)与ZrO_(2)、ZnO以及复合金属氧化物等载体在反应中的差异,提出了CeO_(2)载体催化剂在确认活性关键中间体、兼顾CO_(2)转化率和甲醇选择性、提高催化活性与稳定性等方面的不足和挑战,以期为新型CO_(2)加氢制甲醇催化剂的设计提供有益参考。 展开更多
关键词 二氧化碳 加氢 催化剂 CeO_(2)载体 甲醇 活性
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High activity of a Pt decorated Ni/C nanocatalyst for hydrogen oxidation 被引量:3
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作者 高孝麟 王昱飞 +2 位作者 谢和平 刘涛 储伟 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期396-403,共8页
The Pt decorated Ni/C nanocatalysts were prepared for hydrogen oxidation reaction(HOR) in fuel cell.By regulating the contents of Pt and Ni in the catalyst,both the composition and the structure affected the electro... The Pt decorated Ni/C nanocatalysts were prepared for hydrogen oxidation reaction(HOR) in fuel cell.By regulating the contents of Pt and Ni in the catalyst,both the composition and the structure affected the electrochemical catalytic characteristics of the Pt-Ni/C catalysts.When the Pt mass content was 3.1% percent and that of Ni was 13.9% percent,the Pt-Ni/C-3 catalyst exhibited a larger electrochemically active surface area and a higher exchange current density toward HOR than those of pure supported platinum sample.Our study demonstrates a feasible approach for designing the more efficient catalysts with lower content of noble metal for HOR in fuel cell. 展开更多
关键词 Platinum catalyst Galvanic displacement Nickel supported on carbon Hydrogen oxidation reaction Electrochemically active surface
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Study on the Active Phases of Ni-W System Hydrotreating Catalysts
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作者 Shi Yahua, Qu Lianglong, Wu Dingjun, Jin Zeming, Li Dadong Part of the work were done by Xue Yongfang, and Sun Naijian. (Research Institute of Petroleum Processing, Beijing 100083) 《石油学报(石油加工)》 EI CAS CSCD 北大核心 1997年第S1期52-57,共6页
StudyontheActivePhasesofNiWSystemHydrotreatingCatalystsShiYahua,QuLianglong,WuDingjun,JinZeming,LiDadong(R... StudyontheActivePhasesofNiWSystemHydrotreatingCatalystsShiYahua,QuLianglong,WuDingjun,JinZeming,LiDadong(ResearchInstituteo... 展开更多
关键词 HYDROTREATING catalyst Ni W carbon support ACTIVE phase
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Modification of Ni/SiO_2 Catalysts by Means of a Novel Plasma Technology
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作者 李育亮 刘改焕 +3 位作者 宋磊 储伟 戴晓雁 印永祥 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第5期551-555,共5页
Atmospheric high frequency cold plasma jet was applied to modify Ni/SiO2 catalysts. The catalysts prepared by two different methods with plasma jet were compared with conventional catalysts. BET, XRD, H2-TPD and high-... Atmospheric high frequency cold plasma jet was applied to modify Ni/SiO2 catalysts. The catalysts prepared by two different methods with plasma jet were compared with conventional catalysts. BET, XRD, H2-TPD and high-resolution transmission electron microscopy (HRTEM) were used to characterize these catalysts. The results showed that the catalyst prepared with plasma jet had higher nickel dispersion, larger specific surface area and smaller nickel particle size, about 5 nanometres. Detailed analyses revealed that improved structure and characteristic of the plasma catalyst were benefited from the large amount of hydrogen atoms in the plasma jet, by which the catalyst reduction can be easily achieved in shorter period of time at lower temperature, thus avoiding sintering and conglomeration of the active particles and the support. The activity of catalysts was investigated in the methane reforming with CO2. It is shown that the conversions of CH4 and CO2, the yields of H2 and CO were all significantly increased for the plasma catalysts. 展开更多
关键词 plasma-reduced nickel-based catalyst silica gel support low-temperature activity methane reforming with carbon dioxide
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碳载铁基双金属活化过硫酸盐降解有机污染物 被引量:3
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作者 韩瑞瑞 郑瑾 +5 位作者 高春阳 杜显元 邹德勋 陈宏坤 张晓飞 宋权威 《环境科学与技术》 CAS CSCD 北大核心 2023年第S01期102-108,共7页
过硫酸盐高级氧化技术因具有氧化性强、稳定性高、药剂易于运输等特点,被广泛应用于有机污染场地的修复中,在环境治理领域具有广阔的应用前景。通常过硫酸盐需要激活才能有效地去除有机物,碳载铁基双金属材料因碳材料的多孔结构和高比... 过硫酸盐高级氧化技术因具有氧化性强、稳定性高、药剂易于运输等特点,被广泛应用于有机污染场地的修复中,在环境治理领域具有广阔的应用前景。通常过硫酸盐需要激活才能有效地去除有机物,碳载铁基双金属材料因碳材料的多孔结构和高比表面积可以提高金属的分散性,而且还可以吸附目标污染物,是一种能够高效活化过硫酸盐降解有机污染物的激活剂。该研究在关注碳载铁基双金属的制备方法的基础上,分析了碳载双金属活化过硫酸盐氧化体系的主要机制,探讨了影响碳载铁基双金属活化过硫酸盐体系降解效率的主要影响因素及碳载铁基双金属材料的稳定性,并进一步展望了碳载铁基双金属活化过硫酸盐体系降解有机污染物的研究方向和发展趋势。 展开更多
关键词 碳载铁基双金属 过硫酸盐 有机污染物 活化 自由基
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乙炔氢氯化多元铜基催化剂的制备及应用 被引量:1
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作者 陈方永 邹明军 +2 位作者 罗思宇 陈俊达 高歌 《现代化工》 CAS CSCD 北大核心 2023年第7期136-141,共6页
以CuCl_(2)为活性组分、非贵金属SnCl_(4)和BiCl_(3)为助剂,采用等体积浸渍法制备多元铜基催化剂。结果表明,在反应温度150℃、V(HCl)/V(C_(2)H_(2))=1.10、乙炔空速为315 h^(-1)的条件下,10%CuCl_(2)-5%SnCl_(4)-1%BiCl_(3)/AC三元催... 以CuCl_(2)为活性组分、非贵金属SnCl_(4)和BiCl_(3)为助剂,采用等体积浸渍法制备多元铜基催化剂。结果表明,在反应温度150℃、V(HCl)/V(C_(2)H_(2))=1.10、乙炔空速为315 h^(-1)的条件下,10%CuCl_(2)-5%SnCl_(4)-1%BiCl_(3)/AC三元催化剂的初始活性达到50%;乙炔氢氯化反应9.5 h后,催化活性依然超过相同条件下的汞催化剂。BET、H_(2)-TPR和XPS表征分析结果表明,乙炔氢氯化反应发生在催化剂微孔内;Sn助剂提高了催化剂的抗还原性,稳定了Cu活性组分的价态,从而改善了铜基催化剂的初始活性。 展开更多
关键词 乙炔氢氯化 固定床 催化剂 活性炭载体 助剂
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铁酸钴复合碳纳米管活化过硫酸盐降解铬黑T的性能及机理
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作者 龚鹏程 严群 +2 位作者 陈锦富 温俊宇 苏晓洁 《化工进展》 EI CAS CSCD 北大核心 2023年第7期3572-3581,共10页
采用水热法制备了不同质量比铁酸钴/碳纳米管(CoFe_(2)O_(4)/CNT)复合材料,并将其用于活化过一硫酸盐(PMS)降解偶氮染料铬黑T(EBT)。使用扫描电镜、X射线衍射仪、X射线光电子能谱仪等方法进行了表征。结果表明,引入CNT改善了CoFe_(2)O_... 采用水热法制备了不同质量比铁酸钴/碳纳米管(CoFe_(2)O_(4)/CNT)复合材料,并将其用于活化过一硫酸盐(PMS)降解偶氮染料铬黑T(EBT)。使用扫描电镜、X射线衍射仪、X射线光电子能谱仪等方法进行了表征。结果表明,引入CNT改善了CoFe_(2)O_(4)团聚现象,同时CNT加速CoFe_(2)O_(4)表面电子转移过程进一步提高了CoFe_(2)O_(4)催化活性。质量比为4∶1的CoFe_(2)O_(4)/CNT表现出最高催化活性,CoFe_(2)O_(4)/CNT-4∶1+PMS降解EBT过程符合准一级动力学模型,其反应速率常数是CoFe_(2)O_(4)+PMS体系的2.02倍。单因素条件实验得出在CoFe_(2)O_(4)/CNT-4∶1投加量为0.20g/L、PMS投加量为0.20g/L、EBT质量浓度为100mg/L、pH为5.8、反应温度为25℃条件下,反应60min后EBT降解率可达到99.8%。CoFe_(2)O_(4)/CNT-4∶1循环使用三次后EBT降解率能达到67.8%。猝灭实验证明反应体系中存在着SO_(4)^(-)·、·OH、O_(2)^(-)·和^(1)O_(2)四种活性物质,其中^(1)O_(2)是主要活性物质。Fe^(2+)/Fe^(3+)、Co^(2+)/Co^(3+)价态循环和氧物种改变促进了活性物质生成。 展开更多
关键词 铁酸钴 碳纳米管 活化作用 催化剂载体 降解
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活性炭负载金属催化剂催化合成三联苯的性能研究
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作者 刘俊成 刘东东 +3 位作者 詹石玉 李神勇 常涛 康莲薇 《现代化工》 CAS CSCD 北大核心 2023年第S02期188-191,196,共5页
采用浸渍煅烧法制备了改性活性炭负载复合金属催化剂,考察了活性炭改性条件对合成三联苯的影响。结果表明,活性炭载体经10%磷酸改性、添加10%~35%载体质量的CuFeZn复合氧化物,在反应温度为85℃、70℃下老化48 h、550℃煅烧4 h后制得催化... 采用浸渍煅烧法制备了改性活性炭负载复合金属催化剂,考察了活性炭改性条件对合成三联苯的影响。结果表明,活性炭载体经10%磷酸改性、添加10%~35%载体质量的CuFeZn复合氧化物,在反应温度为85℃、70℃下老化48 h、550℃煅烧4 h后制得催化剂,研磨颗粒至60目。该催化剂用于三联苯合成可显著提高其选择性,减少四联苯、五联苯等副产物的产生,提高了以苯为原料合成氢化三联苯导热油的纯度和产品性能。 展开更多
关键词 纯苯 活性炭负载型催化剂 有机热载体 三联苯
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费托合成催化剂表面碳-氧键活化的研究
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作者 梁嘉音 陆小军 《当代化工研究》 CAS 2023年第23期188-190,共3页
本研究针对费托合成反应中催化剂的活性相,即金属碳化物的生成进行了表面碳-氧键活化的研究。在催化剂的预处理阶段,采用CO对铁基催化剂和钴基催化剂进行渗碳处理,形成碳化铁和碳化钴。XRD图和TEM图的分析结果证实了产物的形成。进一步... 本研究针对费托合成反应中催化剂的活性相,即金属碳化物的生成进行了表面碳-氧键活化的研究。在催化剂的预处理阶段,采用CO对铁基催化剂和钴基催化剂进行渗碳处理,形成碳化铁和碳化钴。XRD图和TEM图的分析结果证实了产物的形成。进一步的实验结果表明,钴基催化剂的目标产物选择性高于铁基催化剂。通过密度泛函理论模拟计算,发现铁基催化剂表面碳-氧键的活化能力低于钴基催化剂,差异为1.26eV。因此,钴基催化剂在费托合成反应中具有更高的活性和选择性。 展开更多
关键词 铁基催化剂 钴基催化剂 碳-氧键活化 活化能力 理论计算
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碳负载的CoMn活化过硫酸盐降解罗丹明B的研究
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作者 岳丽娟 郝良芸 +1 位作者 张俊凯 陈春光 《广州化学》 CAS 2023年第6期51-56,I0003,共7页
采用水热法成功合成了碳负载的CoMn双金属催化剂,并考察了催化剂活化过硫酸盐(PMS)降解RhB的性能。用X射线衍射、X射线光电子能谱仪测定和扫描电子显微镜对催化剂进行表征,结果表明,催化剂由无定形碳、CoO、Co和无定形锰物种组成,CoMn... 采用水热法成功合成了碳负载的CoMn双金属催化剂,并考察了催化剂活化过硫酸盐(PMS)降解RhB的性能。用X射线衍射、X射线光电子能谱仪测定和扫描电子显微镜对催化剂进行表征,结果表明,催化剂由无定形碳、CoO、Co和无定形锰物种组成,CoMn双金属颗粒均匀的负载在碳表面。在25℃室温、初始pH4.7时,投加0.02 g/L的催化剂、0.04 g/L的PMS,反应4 min后,RhB(50 mg/L)达到100%的去除率。阴离子(NO_(3)^(-)和Cl^(-))和天然有机物腐殖酸(HA)存在时,RhB的降解均受到不同程度的抑制。循环结果表明,在重复使用4次后,RhB的降解率在4min时仍能达到88.04%,表明该催化剂具有良好的稳定性。 展开更多
关键词 碳负载的CoMn双金属催化剂 活化过硫酸盐 降解 罗丹明B 稳定性
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