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Investigating the Effect of Catalyst Type and Concentration on the functional Group Conversion in Castor Seed Oil Alkyd Resin Production
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作者 Chigozie F. Uzoh Joseph T. Nwabanne 《Advances in Chemical Engineering and Science》 2016年第2期190-200,共11页
Significant scientific and economic benefits may be derived from investigating the best choice of catalyst in the alkyd resin synthesis. The effect of catalyst type and concentration on the production of alkyd resin u... Significant scientific and economic benefits may be derived from investigating the best choice of catalyst in the alkyd resin synthesis. The effect of catalyst type and concentration on the production of alkyd resin using castor seed oil (CSO) was evaluated. Lithium hydroxide, lead (II) oxide, calcium carbonate, sodium hydroxide and calcium oxide were investigated. The fatty acid profile of the raw CSO was determined using GC-MS while structural elucidation of the CSO based alkyd resins was determined using FTIR spectrometry. The CSO modified alkyd resin produced has acid values of 5.0, 5.61, 7.0 8.24 and 11 for lithium hydroxide, lead (II) oxide, calcium carbonate, sodium hydroxide and calcium oxide respectively. The extent of reaction was 95%, 95%, 91%, 89% and 88% for lithium hydroxide, lead (II) oxide, calcium carbonate, sodium hydroxide and calcium oxide respectively at the reaction time of 150 minutes. The alcoholysis reaction completion time was fastest in LiOH followed by PbO, CaCO<sub>3</sub>, NaOH and CaO catalyst. Physico-chemical parameters of the oil and performance evaluation of the alkyd films suggest that they are sustainable materials for surface coating. LiOH shows excellent robustness to expanded process parameters. 展开更多
关键词 ALCOHOLYSIS Alkyd Resin Dehydrated Castor Seed Oil catalyst type GC-MS
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Simultaneous catalytic removal of NOx and diesel soot particulate over perovskite-type oxides and supported Ag catalysts 被引量:4
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作者 LiuZM HaoZP 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第3期289-295,共7页
A series of perovskite type oxides and supported Ag catalysts were prepared, and characterized by X ray diffraction (XRD) and X ray photoelectron spectroscopy (XPS). The catalytic activities of the catalyst... A series of perovskite type oxides and supported Ag catalysts were prepared, and characterized by X ray diffraction (XRD) and X ray photoelectron spectroscopy (XPS). The catalytic activities of the catalysts as well as influencing factors on catalytic activity have been investigated for the simultaneous removal of NOx and diesel soot particulate. An increase in catalytic activity for the selective reduction of NOx was observed with Ag addition in these perovskite oxides, especially with 5% Ag loading. This catalyst could be a promising candidate of catalytic material for the simultaneous elimination of NOx and diesel soot. 展开更多
关键词 perovskite type catalysts supported Ag catalyst NOx diesel soot
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Removal of VOCs from gas streams with double perovskite-type catalysts 被引量:9
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作者 Kuan Lun Pan Guan Ting Pan +1 位作者 Siewhui Chong Moo Been Chang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第7期205-216,共12页
Double perovskite-type catalysts including La2 CoMnO6 and La2 CuMnO6 are first evaluated for the effectiveness in removing volatile organic compounds(VOCs), and single perovskites(La CoO3, LaMnO3, and La Cu O3) ar... Double perovskite-type catalysts including La2 CoMnO6 and La2 CuMnO6 are first evaluated for the effectiveness in removing volatile organic compounds(VOCs), and single perovskites(La CoO3, LaMnO3, and La Cu O3) are also tested for comparison. All perovskites are tested with the gas hourly space velocity(GHSV) of 30,000 hr^-1, and the temperature range of100–600℃ for C7H8 removal. Experimental results indicate that double perovskites have better activity if compared with single perovskites. Especially, toluene(C7H8) can be completely oxidized to CO2 at 300℃ as La2 Co MnO6 is applied. Characterization of catalysts indicates that double perovskites own unique surface properties and are of higher amounts of lattice oxygen,leading to higher activity. Additionally, apparent activation energy of 68 k J/mol is calculated using Mars-van Krevelen model for C7 H8 oxidation with La2 Co Mn O6 as catalyst. For durability test, both La2 Co Mn O6 and La2 CuMnO6 maintain high C7 H8 removal efficiencies of 100% and98%, respectively, at 300℃ and 30,000 hr^-1, and they also show good resistance to CO2(5%) and H2 O(g)(5%) of the gas streams tested. For various VOCs including isopropyl alcohol(C3H8 O),ethanal(C2H4O), and ethylene(C2H4) tested, as high as 100% efficiency could be achieved with double perovskite-type catalysts operated at 300–350℃, indicating that double perovskites are promising catalysts for VOCs removal. 展开更多
关键词 Volatile organic compounds(VOCs) Toluene(C7H8) Double perovskite-type catalyst Catalysis Activation energy
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Preparation and characterization of La_(0.8)Cu_(0.2) MnO_(3±δ) perovskite-type catalyst for methane combustion 被引量:2
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作者 何方 王华 戴永年 《中国有色金属学会会刊:英文版》 EI CSCD 2005年第3期691-696,共6页
La<sup>0.8 Cu<sup>0.2 MnO<sup>3±δ perovskite-type catalyst for methane combustion prepared through sol-gel process was characterized by X-ray Diffractometry(XRD), X-ray Photoelectron Spectros... La<sup>0.8 Cu<sup>0.2 MnO<sup>3±δ perovskite-type catalyst for methane combustion prepared through sol-gel process was characterized by X-ray Diffractometry(XRD), X-ray Photoelectron Spectroscopy(XPS) and Scanning Electron Microscopy(SEM). XPS analyses reveal that the surface characteristics of the catalyst are changed. The lattice defects and oxygen vacancies on the catalyst surface are enhanced due to a part of La3+ being substituted by Cu2+ . Temperature-programmed-desorption(TPD) and temperature-programmed-reduction(TPR) analyses were carried out to study the catalytic behavior. It is found that there are two O2-desorption peaks at 350℃ and 650℃ in the TPD pattern, and two CH4-consumption peaks at 420℃ and 750℃ in the TPR patterns respectively, which indicates that the two kinds of oxygen species, so-called α and β oxygen, can react with the methane during catalytic combustion process. The catalytic activity tests were performed in a fixed-bed reactor, and the results show that the T<sup>1/2 at which the conversion of methane attains 50% of La<sup>0.8 Cu<sup>0.2 MnO<sup>3±δ is lower by 55℃ than that of LaMnO3. This indicates that the catalytic activity of-La<sup>0.8 Cu<sup>0.2 MnO<sup>3±δ is increased with partial substitution of Cu2+ for La3+ .- 展开更多
关键词 钙铁矿催化剂 甲烷燃烧 溶胶-凝胶法 TPD-TPR-MS特征
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Deep oxidative desulfurization of gas oil based on sandwich-type polysilicotungstate supported β-cyclodextrin composite as an efficient heterogeneous catalyst 被引量:4
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作者 Mohammad Ali Rezvani Sahar Khandan +1 位作者 Negin Sabahi Hamid Saeidian 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第10期2418-2426,共9页
In this work,in order to obtain deep clean gas oil,a novel organic–inorganic hybrid(n-C4H9)4N)7H5Si2W18Cd4O68@β-cyclodextrin(abbreviated as TBA-Si WCd@β-CD)composite was synthesized by supporting quaternary ammoniu... In this work,in order to obtain deep clean gas oil,a novel organic–inorganic hybrid(n-C4H9)4N)7H5Si2W18Cd4O68@β-cyclodextrin(abbreviated as TBA-Si WCd@β-CD)composite was synthesized by supporting quaternary ammonium salt of sandwich-type polysilicotungstate onβ-cyclodextrin(TBA-SiWCd@β-CD)as an efficient catalyst for oxidative desulfurization(ODS)of gas oil.The successful composition of the materials explained by the formation of host–vip inclusion complex,which confirmed through FTIR,UV–vis,XRD,SEM,and EDX characterization analyses.Experimental results revealed that the levels of sulfur content and mercaptan compounds of gas oil lowered with 97%removal efficiency.Compared with the ODS treatment of gas oil,the TBA-Si WCd@β-CD composite showed an outstanding catalytic performance for the oxidation of dibenzothiophene(DBT)in the prepared model fuel.The main factors that influence the desulfurization efficiency and the kinetic study of the ODS process were investigated.The prepared heterogeneous catalyst was found to give remarkable reusability for five runs without a discernible decrease in its activity.This study suggested the potential application of the TBA-Si WCd@β-CD catalyst for removal of hazardous sulfur compounds from gas oil fuel. 展开更多
关键词 OXIDATIVE DESULFURIZATION SANDWICH-type POLYOXOMETALATE Β-CYCLODEXTRIN Heterogeneous catalyst
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Synthesis of Methyl-(γ-chloropropyl)dichlorosilane Catalyzed by Silica-supported Karstedt-type Catalyst
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作者 Zheng Ping FANG Hai Tang YANG +1 位作者 Qian Jiang MIAO Guo Ping CAI 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第9期1155-1158,共4页
Methyl-(γ-chloropropyl)dichlorosilane was synthesized under the catalysis of a silicasupported Karstedt-type catalyst. By orthogonal experimental design method, the optimum reaction parameters such as reactants rat... Methyl-(γ-chloropropyl)dichlorosilane was synthesized under the catalysis of a silicasupported Karstedt-type catalyst. By orthogonal experimental design method, the optimum reaction parameters such as reactants ratio, reaction temperature and time, and the dosage of catalyst, were determined. At the optimum reaction condition the product yield reached 78.42%, which is higher than that reported in the literatures. 展开更多
关键词 Methyl-(γ-chloropropyl)dichlorosilane silica-supported Karstedt-type catalyst hydrosilylation synthesis.
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The Stereoselective Epoxidation by a New Type of Soluble Polymer-Supported Catalysts
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作者 Wang Yongmei Wang Xin Liu Juyan 《合成化学》 CAS CSCD 2004年第z1期101-101,共1页
关键词 The Stereoselective Epoxidation by a New type of Soluble Polymer-Supported catalysts
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晶种法制备MWW型沸石分子筛用于甲烷脱氢芳构化反应研究
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作者 李卫强 董新法 +4 位作者 樊栓狮 郎雪梅 王燕鸿 钟鎏盈 李刚 《低碳化学与化工》 北大核心 2026年第1期32-39,62,共9页
甲烷脱氢芳构化(MDA)是非石油路线制备芳烃的重要途径,探讨催化剂的孔道结构对其MDA反应催化性能的影响,在指导高性能催化剂的制备上具有重要意义。通过晶种法合成了MWW型沸石分子筛(MCM-56和MCM-22),采用XRD、TEM、SEM和N2吸/脱附对Mo/... 甲烷脱氢芳构化(MDA)是非石油路线制备芳烃的重要途径,探讨催化剂的孔道结构对其MDA反应催化性能的影响,在指导高性能催化剂的制备上具有重要意义。通过晶种法合成了MWW型沸石分子筛(MCM-56和MCM-22),采用XRD、TEM、SEM和N2吸/脱附对Mo/MCM-56和Mo/MCM-22催化剂的物相、形貌和孔道结构进行了表征分析,并探究了MWW型沸石分子筛中不同孔道体系对Mo/MCM-56和Mo/MCM-22催化剂的MDA反应催化性能的影响。结果表明,晶种法大幅缩短了沸石分子筛的晶化时间,且MWW型沸石分子筛结构与晶种结构密切相关。在相同条件下(700℃、100 kPa)反应9.0 h后,Mo/MCM-22催化剂比Mo/MCM-56催化剂具有更高的芳烃选择性(95%左右)与芳烃产率(7.5%左右)以及更优异的催化稳定性,从而推测Mo/MCM-22催化剂中通过二维MWW沸石纳米片缩合形成的十二元环超笼是MDA反应的主要场所。本研究揭示了MWW型沸石分子筛中不同孔道体系对催化剂的MDA反应催化性能具有重要影响,以期为高产物选择性、高稳定性MDA催化剂的设计提供新思路。 展开更多
关键词 甲烷脱氢芳构化 MWW型沸石 催化剂 晶种法
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La_(1-x)Ca_xMn_(1-y)Al_yO_3 perovskites as efficient catalysts for two-step thermochemical water splitting in conjunction with exceptional hydrogen yields 被引量:5
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作者 Lulu Wang Mohammad Al‐Mamun +3 位作者 Porun Liu Yun Wang Hua Gui Yang Huijun Zhao 《Chinese Journal of Catalysis》 EI CSCD 北大核心 2017年第6期1079-1086,共8页
Solar‐driven thermochemical water splitting represents one efficient route to the generation of H2as a clean and renewable fuel.Due to their outstanding catalytic abilities and promising solar fuel production capacit... Solar‐driven thermochemical water splitting represents one efficient route to the generation of H2as a clean and renewable fuel.Due to their outstanding catalytic abilities and promising solar fuel production capacities,perovskite‐type redox catalysts have attracted significant attention in this regard.In the present study,the perovskite series La1‐xCaxMn1‐yAlyO3(x,y=0.2,0.4,0.6,or0.8)was fabricated using a modified Pechini method and comprehensively investigated to determine the applicability of these materials to solar H2production via two‐step thermochemical water splitting.The thermochemical redox behaviors of these perovskites were optimized by doping at either the A(Ca)or B(Al)sites over a broad range of substitution values,from0.2to0.8.Through this doping,a highly efficient perovskite(La0.6Ca0.4Mn0.6Al0.4O3)was developed,which yielded a remarkable H2production rate of429μmol/g during two‐step thermochemical H2O splitting,going between1400and1000°C.Moreover,the performance of the optimized perovskite was found to be eight times higher than that of the benchmark catalyst CeO2under the same experimental conditions.Furthermore,these perovskites also showed impressive catalytic stability during two‐step thermochemical cycling tests.These newly developed La1‐xCaxMn1‐yAlyO3redox catalysts appear to have great potential for future practical applications in thermochemical solar fuel production. 展开更多
关键词 Two‐step thermochemical route Water splitting Solar fuel Perovskite‐type redox catalyst Hydrogen production
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Different effect of NiMnCo or FeNiCo on the growth of type-Ⅱa large diamonds with Ti/Cu as nitrogen getter 被引量:4
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作者 李尚升 张贺 +7 位作者 宿太超 胡强 胡美华 龚春生 马红安 贾晓鹏 李勇 肖宏宇 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期454-458,共5页
In order to synthesize high-quality type-Ⅱa large diamond, the selection of catalyst is very important, in addition to the nitrogen getter. In this paper, type-IIa large diamonds are grown under high pressure and hig... In order to synthesize high-quality type-Ⅱa large diamond, the selection of catalyst is very important, in addition to the nitrogen getter. In this paper, type-IIa large diamonds are grown under high pressure and high temperature(HPHT) by using the temperature gradient method(TGM), with adopting Ti/Cu as the nitrogen getter in Ni70Mn25Co5(abbreviated as NiMnCo) or Fe(55)Ni(29)Co(16)(abbreviated FeNiCo) catalyst. The values of nitrogen concentration(Nc) in both synthesized high-quality diamonds are less than 1 ppm, when Ti/Cu(1.6 wt%) is added in the FeNiCo or Ti/Cu(1.8 wt%) is added in the NiMnCo. The difference in solubility of nitrogen between both catalysts at HPHT is the basic reason for the different effect of Ti/Cu on eliminating nitrogen. The nitrogen-removal efficiency of Ti/Cu in the NiMnCo catalyst is less than in the FeNiCo catalyst. Additionally, a high-quality type-Ⅱa large diamond size of 5.0 mm is obtained by reducing the growth rate and keeping the nitrogen concentration of the diamond to be less than 1 ppm, when Ti/Cu(1.6 wt%) is added in the FeNiCo catalyst. 展开更多
关键词 high pressure and high temperature catalyst nitrogen getter type-Ⅱa large diamond
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Efficient Addition Polymerization of Norbornene with Polar Norbornene Derivatives by Neutral Nickel(Ⅱ) Catalysts 被引量:1
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作者 Ling Guo Yan-Ping Zhang +6 位作者 Hong-Liang Mu Li Pan Kai-Ti Wang Huan Gao Bin Wang Zhe Ma Yue-Sheng Li 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2019年第12期1215-1223,I0005,共10页
A series of nickel complexes{4 a:[(2,6-iPr2C6H3)N=CHC16H12O]Ni(Me)(Py),4b:[(2,6-iPr2C6H2OCH3)N=CHC16H12O]-Ni(Me)(Py),4 c:[(2,6-iPr2C6H2Cl)N=CHC16H12O]Ni(Me)(Py),and 4d:[(2,6-iPr2C6H2CF3)N=CHC16H12O]Ni(Me)(Py)}based on... A series of nickel complexes{4 a:[(2,6-iPr2C6H3)N=CHC16H12O]Ni(Me)(Py),4b:[(2,6-iPr2C6H2OCH3)N=CHC16H12O]-Ni(Me)(Py),4 c:[(2,6-iPr2C6H2Cl)N=CHC16H12O]Ni(Me)(Py),and 4d:[(2,6-iPr2C6H2CF3)N=CHC16H12O]Ni(Me)(Py)}based onβ-ketiminato ligands bearing various electron-donating or electron-withdrawing substituents on the para-position of the aniline group were synthesized and unambiguously characterized.The X-ray crystallographic analysis showed that complexes 4 b and 4 d adopted a nearsquare-planar geometry,and the anilines bearing a para-OMe or―CF3 group were found to situate on the axial position of the metal center.All complexes exhibited high activities up to 1.25×10^7–1.35×10^7 g PNB·molNi^–1·h^–1 toward norbornene(NBE)addition polymerization(conversion>91.2%in 2 min)under low loading of B(C6F5)3(B/Ni=3)at 30°C,affording polymers with high molecular weight up to 2.54×10^6–3.18×10^6.Different levels of decrease in catalytic activities could be observed for all catalysts as the reaction temperature increased;4 d bearing a strong electron-withdrawing―CF3 group showed the highest activity at 70°C,while others exhibited notable decrease in catalytic activity with the raise in reaction temperature.Complexes 4 a–4 d showed remarkable tolerance to polar groups and could efficiently promote the copolymerization of NBE with its polar derivatives,including NBE bearing small acetate and hydroxyl group,as well as bulky oligomers,yielding copolymers with high functional NBE incorporations.Novel NBE copolymers with high functional comonomer incorporations and improved solubility were obtained in high yields. 展开更多
关键词 NEUTRAL NICKEL catalystS NORBORNENE NORBORNENE derivatives Vinyl-type polymerization
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Mannich-Type Reactions of Aldimines and Hetero Diels-Alder Reactions of Aldehydes Catalyzed by Anion-Type Lewis Bases Derived from a Single Molecule
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作者 Kaori Ishimaru Daiki Maeda +1 位作者 Kaori Ono Yuya Tanimura 《International Journal of Organic Chemistry》 2012年第3期188-193,共6页
Mannich-type reactions of aldimines with silyl enolates and hetero Diels-Alder reactions of aldehydes with Danishef-sky’s diene in the presence of anion catalysts derived from proline were performed to afford the cor... Mannich-type reactions of aldimines with silyl enolates and hetero Diels-Alder reactions of aldehydes with Danishef-sky’s diene in the presence of anion catalysts derived from proline were performed to afford the corresponding products in high yields. 展开更多
关键词 ANION catalyst Lewis Base PROLINE Mannich-type REACTION Hetero Diels-Alder REACTION
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Direct Decomposition of NO into N<sub>2</sub>and O<sub>2</sub>Over C-type Cubic Y<sub>2</sub>O<sub>3</sub>-Tb<sub>4</sub>O<sub>7</sub>-ZrO<sub>2</sub>
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作者 Toshiyuki Masui Shunji Uejima +1 位作者 Soichiro Tsujimoto Nobuhito Imanaka 《Materials Sciences and Applications》 2012年第10期733-738,共6页
Catalytic activities for direct NO decomposition were investigated over C-type cubic Y2O3–Tb4O7–ZrO2 prepared by a coprecipitation method. The NO decomposition activity was enhanced by partial substitution of the yt... Catalytic activities for direct NO decomposition were investigated over C-type cubic Y2O3–Tb4O7–ZrO2 prepared by a coprecipitation method. The NO decomposition activity was enhanced by partial substitution of the yttrium sites with terbium in a (Y0.97Zr0.03)2O3.03 catalyst, which shows high NO decomposition activity. Among the catalysts synthesized in this study, the (Y0.67Tb0.30Zr0.03)2O3.33 catalyst exhibited the highest NO decomposition activity;NO conversion to N2 was as high as 67% at 900℃ in the absence of O2 (NO/He atmosphere), and a relatively high conversion ratio was observed even in the presence of O2 or CO2, compared with those obtained over conventional direct NO decomposition catalysts. These results indicate that the C-type cubic Y2O3–Tb4O7–ZrO2 catalyst is a new potential candidate for direct NO decomposition. 展开更多
关键词 Nitrogen Monoxide Direct Decomposition catalyst Rare Earth Oxide C-type CUBIC Structure
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稠油开发过程中催化改质降黏研究进展
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作者 林日亿 刘瑞琦 +6 位作者 张立强 韩昕璐 王奕雅 黄晨醒 李化南 董琪伟 朱传涛 《世界石油工业》 2025年第6期48-59,共12页
为了解决稠油因高黏度和流动性差所带来的开采与集输难题,采用系统综述与对比分析的研究方法,考察了催化改质降黏技术的发展现状。研究重点围绕催化剂制备方法、催化剂类型及其降黏机制展开,具体包括:归纳浸渍法、微乳液法等主流催化剂... 为了解决稠油因高黏度和流动性差所带来的开采与集输难题,采用系统综述与对比分析的研究方法,考察了催化改质降黏技术的发展现状。研究重点围绕催化剂制备方法、催化剂类型及其降黏机制展开,具体包括:归纳浸渍法、微乳液法等主流催化剂制备工艺的优势与局限;比较水溶性、油溶性、双亲性、固体酸、矿物及纳米催化剂的降黏性能与应用特点;阐述水热裂解过程中的加氢断键、分子间作用改变和轻烃稀释等降黏机制。研究结果表明:①浸渍法与微乳液法可用于制备高活性与高稳定性的催化剂;②双亲性催化剂因其特殊的分子结构能够在油水界面有效富集,但其亲水-亲油平衡的优化仍是当前需要解决的技术难题;③水溶性催化剂具有较好的分散性,油溶性催化剂在油相中传递效率较高,固体酸催化剂在无外加氢条件下仍能保持较好活性,矿物类催化剂成本较低但反应条件要求较高,纳米催化剂则因其尺寸效应表现出优异的催化性能;④水热裂解过程中的降黏机制复杂多样,目前对催化剂在油藏环境中的构效关系与反应机理仍缺乏清晰认识。结论认为,未来研究应着力开发高效的中低温催化剂,并深入探究多孔介质中多场耦合作用下的催化降黏过程,从而为稠油的高效开发提供坚实的理论支撑。 展开更多
关键词 稠油降黏 催化改质 催化剂制备 催化剂类型 降黏机制 双亲性催化剂 构效关系 多场耦合
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高熵材料在催化加氢中的研究进展
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作者 卢新宁 高艳妮 +2 位作者 汤小妮 华德润 李剑 《现代化工》 北大核心 2025年第5期55-59,65,共6页
综述了近年来高熵材料、负载型高熵材料和高熵材料为载体三种类型催化剂在催化加氢的应用,分别从热催化、电催化和光催化三种不同类型的加氢进行阐述,并分析了高熵催化剂未来发展需要解决的问题及研究方向。
关键词 负载型 高熵材料 催化剂 催化加氢
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Cu-Mn型CO催化剂催化氧化特性及其影响因素研究 被引量:1
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作者 周露函 姜延航 +2 位作者 李旭 孙亚胜男 王丽新 《中国安全科学学报》 北大核心 2025年第1期127-136,共10页
为探究不同金属掺杂和沉淀温度对Cu-Mn型催化剂催化氧化CO性能的影响,首先采用共沉淀法制备Cu-Mn型CO催化剂,利用自主搭建的试验平台,测试分析不同金属掺杂和沉淀温度条件下Cu-Mn型CO催化剂催化氧化CO特性;然后通过全自动物理吸附仪和X... 为探究不同金属掺杂和沉淀温度对Cu-Mn型催化剂催化氧化CO性能的影响,首先采用共沉淀法制备Cu-Mn型CO催化剂,利用自主搭建的试验平台,测试分析不同金属掺杂和沉淀温度条件下Cu-Mn型CO催化剂催化氧化CO特性;然后通过全自动物理吸附仪和X射线衍射(XRD)分析仪获得催化剂的孔隙特征参数和表面晶型结构,采用原位漫反射红外光谱技术展示催化剂催化氧化CO的反应过程,并介绍催化剂在煤矿井下的应用前景。研究结果表明:试验测试时间内(80 s以内),随着反应时间的增加,CO体积分数表现为逐渐减小、缓慢增加后趋于平缓的变化特征,反应的CO物质的量逐渐增加。催化剂催化氧化CO效果越好,其比表面积越大,平均孔径越小,总孔容越大。当掺杂金属分别为Sn、Fe和Ce时,3种催化剂的催化氧化CO特性强弱由大到小为:CuMnO_(x)-Ce>CuMnO_(x)-Sn>CuMnO_(x)-Fe,参与反应的CO物质的量分别为0.0153、0.0093和0.0203 mol,CO消除效率分别为61%、47%和77%。沉淀温度为70℃时,催化剂的晶核数量要明显高于沉淀温度为60和80℃,当沉淀温度分别为60、70和80℃时,3种催化剂的催化氧化CO特性强弱由大到小为:CuMnO_(x)-Ce-70>CuMnO_(x)-Ce-80>CuMnO_(x)-Ce-60,参与反应的CO物质的量分别为0.01945、0.0203和0.0198 mol,CO消除速率分别为74%、77%和75%。含有丰富的表面氧空位是提高CO氧化反应和催化氧化性能的关键因素,CeO_(2)的存在有助于含碳物种的形成、氧活化和迁移。 展开更多
关键词 Cu-Mn型CO催化剂 催化氧化特性 金属掺杂 沉淀温度 CO体积分数
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二氯二氢硅反歧化装置的工艺优化及工业分析
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作者 向烺 王韬 +4 位作者 陆平 张豪豪 王庆格 陈锦溢 白芳 《现代化工》 北大核心 2025年第8期246-250,共5页
以二氯二氢硅(DCS)和四氯化硅(STC)为原料,通过反歧化反应精馏工艺合成三氯氢硅(TCS)的过程进行系统性工艺优化。根据反应特性确定了适宜的催化剂,考察氯化氢气体、催化剂氮含量、反应温度和反应时间对催化剂活性的影响。为了提升催化... 以二氯二氢硅(DCS)和四氯化硅(STC)为原料,通过反歧化反应精馏工艺合成三氯氢硅(TCS)的过程进行系统性工艺优化。根据反应特性确定了适宜的催化剂,考察氯化氢气体、催化剂氮含量、反应温度和反应时间对催化剂活性的影响。为了提升催化剂活性并满足严格的水分控制要求,提出了一种催化剂预处理方法,包括高纯水洗涤以除去杂质、甲醇脱水以及氮气与氯化氢吹扫,有效提高催化性能。其次采用了新型的催化剂捆扎包的装填方式进行装填,减少了催化剂的磨损,具有催化剂寿命长、操作稳定、操作弹性大等优点。基于理论分析的基础进行工业实验装置设计,并确定了预分离塔和反应精馏塔的控制策略。经过对工艺操作条件的优化,得到了反应精馏塔操作压力为绝压150 kPa,回流量3~4 t/h,塔顶采出温度为50℃的操作条件,将DCS的转化率提高到98.5%以上,并在国内某企业的工业装置上应用,验证了工艺的可行性。 展开更多
关键词 三氯氢硅 二氯二氢硅 四氯化硅 反歧化 反应精馏 新型捆扎包
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反应温度对Zn改性HZSM-5分子筛催化乙烯芳构化性能的影响
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作者 李柏超 邵嘉蓓 +3 位作者 冯鹏程 王建国 樊卫斌 董梅 《燃料化学学报(中英文)》 北大核心 2025年第9期1354-1363,共10页
Zn改性HZSM-5催化剂在乙烯芳构化反应中得到了广泛应用。研究反应温度对HZSM-5和多种Zn改性HZSM-5催化剂催化乙烯芳构化过程的影响,对于设计高效芳构化催化剂和优化工艺条件具有重要意义。通过离子交换、浸渍和物理混合制备了各种Zn改性... Zn改性HZSM-5催化剂在乙烯芳构化反应中得到了广泛应用。研究反应温度对HZSM-5和多种Zn改性HZSM-5催化剂催化乙烯芳构化过程的影响,对于设计高效芳构化催化剂和优化工艺条件具有重要意义。通过离子交换、浸渍和物理混合制备了各种Zn改性的HZSM-5催化剂,采用XRD、ICP、NH_(3)-TPD和Py-FTIR分析了催化剂结构、组成及酸性,比较研究了400-580℃下不同催化剂催化乙烯芳构化的性能。结果表明,随着反应温度的升高,HZSM-5和ZnAl_(2)O_(4)-pure/HZSM-5催化剂的芳烃选择性和由脱氢路线生成的芳烃占比均呈上升趋势;对于Zn(IE)/HZSM-5和ZnAl_(1.5)O/HZSM-5催化剂,芳烃的选择性及脱氢占比迅速增加,然后基本保持不变;Zn(IM)/HZSM-5和Zn(PM)/HZSM-5催化剂的芳烃选择性先增加后基本保持不变,脱氢路线占比保持不变。结合环己烷脱氢动力学实验,证实了Zn物种的引入有助于降低脱氢活化能,催化剂的酸含量与脱氢活化能呈线性关系。由于ZnAl_(2)O_(4)尖晶石不具备催化活性,担载ZnAl_(2)O_(4)尖晶石的HZSM-5催化剂性能和脱氢活化能与HZSM-5非常接近。 展开更多
关键词 含锌HZSM-5催化剂 酸强度和类型 活化能
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电催化CO_(2)还原制甲酸p区金属基催化剂原位重构的研究进展
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作者 董志伟 加亚玲 李文英 《低碳化学与化工》 北大核心 2025年第12期1-10,共10页
通过电催化CO_(2)还原反应(ECO_(2)RR)制备高附加值化学品和燃料,是实现“双碳”目标的有效途径,其中甲酸(HCOOH)是极具经济价值的产物之一。然而,CO_(2)分子的热力学稳定性及ECO_(2)RR中的多质子耦合电子转移过程使反应活性与产物选择... 通过电催化CO_(2)还原反应(ECO_(2)RR)制备高附加值化学品和燃料,是实现“双碳”目标的有效途径,其中甲酸(HCOOH)是极具经济价值的产物之一。然而,CO_(2)分子的热力学稳定性及ECO_(2)RR中的多质子耦合电子转移过程使反应活性与产物选择性受限。p区金属(如Bi、In和Sn等)基催化剂凭借适宜的中间体OCHO*吸附强度,在ECO_(2)RR制HCOOH中表现出较大的潜力。在电化学工作条件下,催化剂表面会因电场诱导、界面反应及化学环境改变而发生重构,这种结构演变使得揭示催化剂的结构与催化性能关系较为困难。鉴于此,聚焦于p区金属基催化剂在ECO_(2)RR过程中的原位重构行为,系统分析了催化剂重构影响因素、重构类型以及表征技术,深入探讨了催化剂在动态工况下的构效关系,总结了在ECO_(2)RR制HCOOH过程中p区金属基催化剂差异化的重构路径与活性位点演化规律,提出了构建“理论计算-机器学习-原位实验”体系的建议,可为设计高稳定性、高产物选择性的重构催化剂提供参考。 展开更多
关键词 电催化CO_(2)还原 甲酸 p区金属基催化剂 催化剂原位重构 重构类型 原位表征技术
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铁捕集回收含铂硫酸钡废催化剂中的铂
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作者 肖雄 杨泉 +5 位作者 方鹏 李瑞 韩继标 杨翰 宁显雄 张天环 《贵金属》 北大核心 2025年第3期46-51,共6页
从催化剂中回收铂族金属是保证我国战略资源的重要措施。对精细化工领域催化加氢过程中产生的含铂硫酸钡废催化剂通过熔炼捕集铂与铁形成铂铁合金,实现铂的富集。理论分析及实验结果表明,采用Al_(2)O_(3)-SiO_(2)-CaO-BaSO_(4)渣系可以... 从催化剂中回收铂族金属是保证我国战略资源的重要措施。对精细化工领域催化加氢过程中产生的含铂硫酸钡废催化剂通过熔炼捕集铂与铁形成铂铁合金,实现铂的富集。理论分析及实验结果表明,采用Al_(2)O_(3)-SiO_(2)-CaO-BaSO_(4)渣系可以较好地富集铂,在假硅灰石渣区内,当磁铁矿添加量为原料质量的10%、焦炭添加量6%、二元碱度1.0,熔炼温度为1550℃,保温时间为2 h的条件下,熔炼渣中Pt含量<6 g/t,实现铂回收率达99.85%,回收效果良好,为含铂硫酸钡废催化剂中铂回收产业化实施奠定基础。 展开更多
关键词 火法熔炼 铁捕集 硫酸钡废催化剂 渣型
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