检索结果-南通市图书馆

乙酸甲酯水解催化精馏过程催化剂包内的传质模型(Ⅰ)数学模型

在线全文

学校读者我要写书评

暂无评论

化工学报 2002年第5期53卷 503-507页

作者：吴燕翔王良恩赵之山谭天恩福州大学化工系福建福州350002 浙江大学化工系浙江杭州310027

分析了催化精馏过程催化剂包内的传质 ,提出催化剂颗粒的不完全润湿和包内反应物浓度的不均匀是造成催化剂效率下降的原因 .催化剂包总效率因子是表征催化剂不完全润湿程度的表面润湿率 ηs 和表征由于包内反应物浓度的不均造成催化剂... 详细信息

分析了催化精馏过程催化剂包内的传质 ,提出催化剂颗粒的不完全润湿和包内反应物浓度的不均匀是造成催化剂效率下降的原因 .催化剂包总效率因子是表征催化剂不完全润湿程度的表面润湿率 ηs 和表征由于包内反应物浓度的不均造成催化剂效率下降的效率因子 ηc 的乘积 .建立了一个二维传质模型 ,给出了 ηc 的计算式 .结果表明 ,ηc 不仅与反映扩散速率的Thiele模数有关 ,还与反映包内液体轴向流速的参数Ψ或γ有关 .由于催化剂包内存在液体的轴向流动。

关键词：催化精馏催化剂包传质模型效率因子数学模型

同方期刊数据库

Electrochemical probing into the active sites of graphitic-layer encapsulated iron oxygen reduction reaction electrocatalysts

在线全文

学校读者我要写书评

暂无评论

Science Bulletin 2018年第1期63卷 24-30页

作者： Lijie Zhong Jens Oluf Jensen Lars Nilausen Cleemann Chao Pan Qingfeng Li Department of Energy Conversion and Storage Technical University of Denmark

The graphitic-layer encapsulated iron-containing nanoparticles(G@Fe) have been proposed as a potential type of active and stable non-precious metal electrocatalysts(NPMCs) for the oxygen reduction reaction(ORR). However, the contribution of the encapsulated components to the ORR activity is still unclear compared with the well-recognized surface coordinated FeN_x/C structure. Using the strong complexing effect of the iron component with anions, cyanide(CN^-) in alkaline and thiocyanate(SCN^-) in acidic media, the metal containing active sites are electrochemically probed. Three representative catalysts are chosen for a comparison including the as-prepared encapsulated G@Fe, commercial Fe/N/C catalyst with iron–nitrogen coordinated surface functionalities and molecular iron phthalocyanine(Fe Pc) containing well-defined structures and compositions. It was found that all samples showed significant shifts of half-wave potentials indicating that surface Fe coordinated sites in all cases. The G@Fe catalyst showed the weakest poisoning effect(the lowest shifts of half-wave potential) compared to the Fe/N/C and Fe Pc catalysts in both electrolytes. These results could be explained that the encapsulated iron components influence the FeN_x/C and/or N_xC surface functionality.

关键词：电气化学含铁地点反应探查催化剂包氧表面功能

在线全文

学校读者我要写书评

暂无评论

非全浸式催化剂包效率因子的测定方法

福州大学学报：自然科学版 1999年第4期27卷 103-107页

作者：赵素英王良恩赵之山颜翊福州大学化学工程系福建福州350002 北京科技大学热能工程系北京100083

设计一种测定非全浸式催化剂包的效率因子装置，

关键词：效率因子催化剂包非全浸式测定催化反应

在线全文

学校读者我要写书评

暂无评论

液固传质系数和催化剂包内液体流速的测定

福州大学学报（自然科学版） 2001年第1期29卷 90-92页

作者：王良恩邱挺吴燕翔赵之山福州大学化学工程系福建福州350002

通过气液在塔内的逆向流动 ,测定了液固传质系数和催化剂包内流速 .实验在常压、2 5℃下进行 ,采用内径为 5 6mm的玻璃管 ,玻璃管中的催化剂捆束总高度为 5 2 8mm .对实验数据进行回归处理 ,得到了一些关联式 ,为醋酸甲酯催化精馏水解... 详细信息

通过气液在塔内的逆向流动 ,测定了液固传质系数和催化剂包内流速 .实验在常压、2 5℃下进行 ,采用内径为 5 6mm的玻璃管 ,玻璃管中的催化剂捆束总高度为 5 2 8mm .对实验数据进行回归处理 ,得到了一些关联式 ,为醋酸甲酯催化精馏水解过程的模拟提供了基础 .

关键词：催化精馏液体流速液固传质系数催化剂包醋酸甲酯溶解速率流量分配测定

湿式氧化用于染料废水脱色:过去20年回顾（英文）

在线全文

学校读者我要写书评

暂无评论

催化学报 2014年第1期35卷 1-7页

作者： Jie Fu George Z.Kyzas Environmental Engineering Program Department of Civil Engineering Auburn University Department of Petroleum and Natural Gas Technology Technological Educational Institute of Kavala Division of Chemical Technology Department of Chemistry Aristotle University of Thessaloniki

Wet air oxidation(WAO), a liquid phase reaction between organic materials in water and oxygen, is one of the most economical and technologically viable advanced oxidation processes for wastewater treatment, particularly toxic and high organic content wastewater. WAO is the liquid phase oxidation of organics or oxidizable inorganic components at elevated temperatures(125–320 °C) and pressures(0.5–20 MPa) using gaseous oxygen(or air) as oxidant. In the past two decades, the WAO process was widely studied and applied in the treatment of dye wastewater. Compared to conventional WAO, catalytic WAO processes have higher efficiency and use moderate reaction conditions. The catalysts included homogenous and heterogeneous types. The key points that need to be solved are recycling of homogenous catalysts and better stability of heterogeneous catalysts. In the present review, the technological processes are first introduced, then some research history and hotspots of WAO research are presented, and finally, its application in the treatment of dye wastewater in the past two decades is summarized to reveal the impressive changes in modes, trends, and conditions used. The application includes model pollutant studies and wastewater tests.

关键词：染料废水处理湿式空气氧化非均相催化剂有机物含量脱色湿式氧化工艺液相反应催化剂包

在线全文

学校读者我要写书评

暂无评论

催化蒸馏技术中催化剂包的有效因子测定

化工学报 1992年第2期43卷 184-189页

作者：王光润秦文军清华大学化工系北京100084

催化蒸馏合成MTBE(甲基叔丁基醚)的一种新结构的催化剂包由不锈钢丝网制成,内灌以催化剂颗粒(40目),催化剂包长20cm、直径2～10cm.化学反应在蒸馏条件下进行.测定了催化剂包的有效因子和表观反应速率常数.通过数学模型计算了不同温度、... 详细信息

催化蒸馏合成MTBE(甲基叔丁基醚)的一种新结构的催化剂包由不锈钢丝网制成,内灌以催化剂颗粒(40目),催化剂包长20cm、直径2～10cm.化学反应在蒸馏条件下进行.测定了催化剂包的有效因子和表观反应速率常数.通过数学模型计算了不同温度、不同直径的催化剂包的有效因子,结果和实测值符合较好.

关键词：催化蒸镏催化剂包效率因子

绿色可磁性分离二氧化硅包裹镍铁尖晶石负载硫酸氢铁纳米粒子催化剂用于合成1,8-二氧十氢吖啶合成(英文)

在线全文

学校读者我要写书评

暂无评论

催化学报 2014年第3期35卷 376-382页

作者： Amir Khojastehnezhad Mohammad Rahimizadeh Hossein Eshghi Farid Moeinpour Mehdi Bakavoli Department of Chemistry Faculty of Sciences Ferdowsi University of Mashhad Mashhad Iran Department of Chemistry Islamic Azad University-Bandar Abbas Branch Bandar Abbas *** Iran

A new magnetically separable catalyst consisting of ferric hydrogen sulfate supported on silica-coated nickel ferrite nanoparticles was prepared.The synthesized catalyst was characterized using vibrating sample magnetometry,X-ray diffraction,transmission electron microscopy,scanning electron microscopy,and Fourier transform infrared spectroscopy.This new magnetic catalyst was shown to be an efficient heterogeneous catalyst for the synthesis of 1,8- dioxodecahydroacridines under solvent-free conditions.The catalyst is readily recovered by simple magnetic decantation and can be recycled several times with no significant loss of catalytic activity.

关键词：催化剂包镍铁氧体硫酸氢磁性分离纳米粒子二氧化硅合成铁素体

在线全文

学校读者我要写书评

暂无评论

催化水解乙酸甲酯及催化剂包有效因子的计算

石化技术与应用 2003年第3期21卷 162-165页

作者：夏代宽李菊梅四川大学化学工程学院四川成都610065

在循环恒温反应装置中,测定了催化水解乙酸甲酯催化剂包的效率因子,归纳得到了液体流量与催化剂包效率因子间的关联式:η包=0.0573L+0.4979;研究了催化精馏水解乙酸甲酯的影响因素,得出乙酸甲酯在反应段底部进料,水从反应段顶部进料为... 详细信息

在循环恒温反应装置中,测定了催化水解乙酸甲酯催化剂包的效率因子,归纳得到了液体流量与催化剂包效率因子间的关联式:η包=0.0573L+0.4979;研究了催化精馏水解乙酸甲酯的影响因素,得出乙酸甲酯在反应段底部进料,水从反应段顶部进料为最佳进料状态。

关键词：催化水解乙酸甲酯催化剂包有效因子计算

Foam/fiber-structured catalysts: non-dip-coating fabrication strategy and applications in heterogeneous catalysis

在线全文

学校读者我要写书评

暂无评论

Science Bulletin 2016年第10期61卷 745-748页

作者： Guofeng Zhao Ye Liu Yong Lu Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular Engineering East China Normal University

Development and use of the structured catalysts and reactors(SCRs)is a promising strategy to overcome the major drawbacks encountered in the traditional packed-bed reactor due to improved hydrodynamics in the combination with enhanced heat/mass transfer,thus being a hot topic in the heterogeneous catalysis.One of the most typical SCRs is the ceramic honeycomb catalyst extensively applied in the control of automotive emissions and the reduction of nitrogen oxides from power stations.Such

关键词：催化剂包多相催化涂层制备应用纤维结构强化传热传质填充床反应器浸渍