连续二氧化碳激光敏化氧化CF2HCL,CF2=CF2,CF2=CFCl,CHCl3,CHCl=CCl2和CH2=CH2

本文报道了连续二氧化碳激光敏化氧化CF_2HCl,CF_2==CF_2,CF_2==CFCL,CHCl_3,CHCl==CCl_2和CH_2==CH_2的反应,讨论了某些反应的机制。结果表明,激光敏化方法可以使不能直接吸收激光的反应物分子在气相中发生反应,并有可能产生卡宾。     

漫反射付立叶红外光谱法研究二氧化碳的催化甲烷化：Ⅰ.Ni／Al2O3体系…

用漫反射付立叶红外光谱法研究了二氧化碳甲烷化催化剂Ｎｉ／Ａｌ２Ｏ３体系的表面物种及催化反应过程。结果表明：二氧化碳难以直接在催化剂表面发生吸烩，而是通过与其它反应物的作用生成含氧酸根类表面吸附物种，并以此为主要中间物进行下一步反应。     

三相界面电催化二氧化碳还原研究进展

电催化二氧化碳还原是能源化学及催化科学的研究重点与难点. 气-固-液三相界面模型作为物理化学中的基本概念, 近年来被越来越多地应用于电催化二氧化碳还原反应的研究, 其相比于传统固-液两相体系表现出了诸多优点. 本综述阐述了三相界面电催化二氧化碳还原研究进展, 对三相界面电催化体系进行分类及原理探究. 再具体到二氧化碳还原反应, 讨论其水下超亲气体系以及气体扩散层体系的结构特性及电催化性质, 并对包括反应物界面扩散及界面浸润性等影响因素进行了系统分析. 最后对当前研究存在的问题及今后电催化二氧化碳还原领域的发展方向进行了总结与展望.     

超临界二氧化碳介质中端炔C—H键与CO_2的羧化反应研究

建立了一个不使用有机溶剂的端炔C—H键羧化新体系:在Ag(I)/DBU(1,8-二氮杂二环十一碳-7-烯)催化体系中,通过超临界二氧化碳与端基炔的羧化反应,以较高产率得到了相应丙炔酸产物.在反应体系中,超临界二氧化碳既是反应物又是反应溶剂;助剂DBU起到了碱、亲核体和共催化剂的作用,并能够明显加快反应速率.筛选出的催化体系具有良好的催化反应活性和底物适应能力,能够实现液态、固态端基炔与超临界二氧化碳的直接羧化反应,为制备功能化丙炔酸类化合物提供了一个环境友好、简单、经济的合成路线.     

硝基甲苯的羧基化反应

近年来,对含有活性氢化合物的羧基化反应有不少报道,并有综述。其中所用的反应物,通常是含有强吸电子基团的化合物,所用的羧基化剂通常是活化了的二氧化碳衍生物,其中应用最广的是碱金属酚盐和二氧化碳作为羧基化剂,以它为羧化剂对脂肪族硝基化合物,氰基类化合物,酯类和酮类化合物能很方便地进行羧基化反应。文献报道的这类反应中的反应物的一个共同特点是强吸电子基团都是直接与含有活性氢的碳原子相连,而对于吸电子基团的效应通过苯环的传递而引起的含活性氢化合物(如邻一硝基甲苯等)的竣基化作用则很少研究。Battaccio等报道对一硝基甲苯在苯酚钠的存在下能与二氧化碳进行竣基化反应生成相应的对一硝基苯乙酸。尚未见邻一硝基甲苯和其它位取代的硝基甲苯的报道。我们以酚钠和二氧化碳为梭基化剂对邻一硝基甲苯的毅基化反应进行了研究。实验表明在所选择的条件下并不明显发生酚环上的敖基化作用。所得硝基苯乙酸,熔点均与文献值相符。     

漫反射付立叶红外光谱法研究二氧化碳的催化甲烷化

用漫反射付立叶红外光谱法（ＤＲＩＦＴ）研究了二氧化碳甲烷化催化剂Ｎｉ／Ａｌ２Ｏ３体系的表面物种及催化反应过程．结果表明：二氧化碳难以直接在催化剂表面发生吸附，而是通过与其它反应物的作用，生成含氧酸根类表面吸附物种，并以此为主要中间物进行下一步反应．含氧酸根类物种主要吸附于载体表面．一氧化碳不是反应的主要中间物，而仅作为一种副产物出现     

不同光照和水质条件下过氧乙酸催化氧化亚硫酸盐的本征反应动力学

亚硫酸盐的氧化是湿法烟气脱硫工艺中的重要过程．分别利用透光和不透光的间歇式反应装置,先后以高纯水和蒸馏水为反应介质,研究了4种条件下过氧乙酸催化氧化亚硫酸盐的本征反应动力学,得到了各反应物的分级数和表观活化能．结果表明,光照和水质条件对反应物的分级数和表观活化能没有明显影响,但改变了反应速率常数．对本征反应的机理进行了推断,结果与实验现象有较好的吻合．     

二氧化碳与低碳经济发展

由于二氧化碳无色无味,又存在于大气中,因此它在植物生长中的重要性被人类忽略了。其实二氧化碳是光合作用的反应物,是植物生长的重要原料;又是一种新型绿色肥料。人类应该着力开发以二氧化碳为原料的新型肥料发展低碳经济。     

粒度对多相反应动力学参数的影响

以纳米氧化锌与硫酸氢钠溶液为反应体系, 研究反应物粒度对动力学参数的影响规律. 讨论了表观活化能降低的原因. 结果表明：当反应物粒径、反应温度和搅拌速率一定时, 纳米氧化锌与硫酸氢钠溶液的反应速率仅与反应物的浓度有关；反应物粒度对多相反应的反应级数、速率常数、表观活化能和指前因子均有较大的影响；随着反应物粒径的减小, 表观活化能和指前因子减小, 而反应级数和速率常数增大, 并且速率常数和表观活化能与反应物粒径的倒数呈线性关系；反应物粒度是通过摩尔表面积、摩尔表面能和摩尔表面熵三个方面影响多相反应的动力学参数的.     

梳型接枝共聚物的合成 (Ⅲ)氯代乙酸 (降冰片烯基) 甲酯的制备

从双环戊二烯与烯丙醇进行Diels-Alder反应合成了5-羟甲基2-降冰片烯2,后者在N.N-二甲基苯胺存在下与a-氯代乙酰氯反应,首次合成出了氯乙酸降冰片烯甲酯2,考察了反应条件 (温度、反应物摩尔比等) 对各步反应收率的影响.并对各步反应产物结构进行表征.     

Design of effective zeolite catalysts for the complete hydrogenation of CO2

Ab initio molecular orbital calculations have been applied to the study of the three-stage zeolite-catalyzed hydrogenation of CO2 to methanol. The results present strong evidence that appropriate chemical modifications to ZSM-5 can lead to significantly lower energy barriers for the three component reactions, that is, hydrogenation of CO2, HCO2H, and CH2O. Zeolites incorporating either Na+ or Ge are more effective catalysts than conventional acidic zeolites for the hydrogenation of CO2 to give HCO2H, but amine-based zeolites do not lead to significantly lower barriers for any of the three hydrogenation reactions. However, we predict that when all three features, namely, Na+, N, and Ge, are incorporated in the zeolite, there is a dramatic improvement in catalytic activity for all three reactions.     

PRODUCTION OF LIGHT ALKENES FROM CO AND/OR CO_2 HYDROGENATION OVER K-Fe-MnO/SILICALITE-2 CATALYST

High selectivity to light alkenes can be achieved from CO and CO_2hydrogenation over K-Fe-MnO/Si-2 catalyst.The alkene selectivity isinsensitive to reaction temperature for CO hydrogenation,while apparentlyincreases for CO_2 hydrogenation with raising reaction temperature.An increasein alkene selectivity is observed for both CO and CO_2 hydrogenation with GHSVrising,While a decrease with the elevation of reaction pressure for both CO/H_2and CO_2/H_2 reaction.A two-step mechanism is suggested forCO_2 hydrogenation to form hydrocarbons,by which the variations incontributions of CO and HC as products of CO_2/H_2 reaction with change ofreaction temperature,GHSV and pressure are explained.Moreover,thecatalyst is favorable for selective production of light olefins,which can alsoconcern the slightly secondary reactions of light olefins to some extent.     

HYDROGENATION OF CO_2 OVER ULTRAFINECuO-ZnO-SiO_2 CATALYST-REACTION CONDITIONS AND MECHANISM

IntroductionAsoncofthemostabundantandcheapestcarbonsourccs,Co2u,ithsteadilyincreasingconcentrationintheatmospherenotonlyleadstothelossofcarbonsource,butalsocausesgrccnhouseeffects.Recently,Co2wastestedasafecdstockformcthanolproductionovcrdiffcrentcatalystsclse.'hcrell'21,butmostofthesecatalystswerebasedonthecombinationofcoppcrandzincandpreparedbycoprecipitation,ioncxchangcor'l3'4]Accordingtoextensivestudiesaboutsupports,SiO2wasoncoftheimpregnationl3'4]Accordingtoextensivestudiesaboutsupport…     

CO2／H2和（CO／CO2）＋H2低压合成甲醇催化过程的本质

通过在Ｃｕ／ＺｎＯ／Ａｌ２Ｏ３催化剂上ＣＯ２＋Ｈ２，ＣＯ＋Ｈ２和（ＣＯ／ＣＯ２）＋Ｈ２催化反应动力学研究对合成甲醇动力学和反应机理进行了细致分析，提出合成甲醇的反应机理，解释了在（ＣＯ／ＣＯ２）＋Ｈ２合成甲醇过程中少量ＣＯ２的作用及合成甲醇的直接碳源。     

合成气制低碳烯烃K－Fe－MnO／MgO催化剂的研究Ⅰ．MnO助剂的作用

采用ＣＯ加氢反应、ＣＯ－ＴＰＤ、ＣＯ／Ｈ＿２－ＴＰＳＲ及Ｃ＿２Ｈ＿４／Ｈ＿２－ＴＰＳＲ等手段，研究合成气制低碳烯烃反应Ｋ－Ｆｅ－ＭｎＯ／ＭｇＯ催化剂中ＭｎＯ的助剂作用。结果表明ＭｎＯ能大幅度提高低碳烯烃的选择性，尤其是乙烯的选择性；ＭｎＯ能抑制催化剂表面的乙烯加氢，因而有利于提高低碳烯烃的选择性及烯／烷的比值。     

First-Principles Microkinetic Study of Methanol Synthesis on Cu(221) and ZnCu(221) Surfaces

First-principle based microkinetic simulations are performed to investigate methanol synthesis from CO and CO₂ on Cu(221) and CuZn(221) surfaces. It is found that regardless of surface structure, the carbon consumption rate follows the order:CO hydrogenation > CO/CO₂ hydrogenation > CO₂ hydrogenation. The superior CO hydrogenation activity mainly arises from the lower barriers of elementary reactions than CO₂ hydrogenation. Compared to Cu(221), the introduction of Zn greatly lowers the activity of methanol synthesis, in particularly for CO hydrogenation. For a mixed CO/CO₂ hydrogenation, CO acts as the carbon source on Cu(221) while both CO and CO₂ contribute to carbon conversion on CuZn(221). The degree of rate control studies show that the key steps that determine the reaction activity of CO/CO₂ hydrogenation are HCO and HCOO hydrogenation on Cu(221), instead of HCOOH hydrogenation on CuZn(221). The present work highlights the effect of the Zn doping and feed gas composition on methanol synthesis.     

EFFECTS OF BINDERS ON THE PRODUCTION OF LIGHT ALKENES FROM SYNGAS OVER K-Fe-MnO/SILICALITE-2 CATALYST Ⅱ. MODIFICATION EFFECT OF Al_2O_3 BINDER ON CO HYDROGENATION

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CO hydrogenation on stepped Cu and CuZn alloy surfaces: Competition between methanol synthesis and methanation pathways

Comprehensive fundamental understanding of CO hydrogenation reactions over Cu and ZnCu alloy surfaces is of great importance. Herein, we report a comparative DFT calculation study of elementary surface reaction network of CO hydrogenation reactions on stepped Cu(211), Cu(611), ZnCu(211) and ZnCu(611) surfaces. On ZnCu(211) and ZnCu(611) surfaces, the energetic favorable reaction path of CO hydrogenation reaction follows CO* → HCO* → H₂CO* → H₃CO* → CH₃OH* → CH₃OH with H₃CO* hydrogenation as the rate-limiting step and proceeds more facilely on ZnCu(611) surface than on ZnCu(211) surface. On Cu(211) and Cu(611) surfaces, the energetic favorable reaction path of CO hydrogenation reaction follows CO* → HCO* → HCOH* → H₂COH* → H₃COH* → CH₃* → CH₄* → CH₄ with H₂COH* hydrogenation as the rate-limiting step and proceeds more facilely on Cu(611) than on Cu(211). The key difference of CO hydrogenation reaction on ZnCu alloy surface and Cu is that the resulting CH₃OH* species desorbs to produce CH₃OH on ZnCu alloy but undergoes H*-assisted decomposition to CH₃* and eventually to CH₄ on Cu surface. These results successfully unveil elementary surface reaction networks and structure sensitivity of Cu and ZnCu alloy-catalyzed CO hydrogenation reactions.     

EFFECTS OF BINDERS ON THE PRODUCTION OF LIGHT ALKENES FROM SYNGAS OVER K-Fe-MnO/SILICALITE-2 CATALYST Ⅰ. EFFECT OF VARIOUS BINDERS ON CO HYDROGENATION

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EFFECTS OF BINDERS ON THE PRODUCTION OF LIGHT ALKENES FROM SYNGAS OVER K-Fe-MnO/SILICALITE-2 CATALYST I. EFFECT OF VARIOUS BINDERS ON CO HYDROGENATION

The performance of the K-Fe-MnO/Si-2 catalyst for the production of light olefins via Co hydrogenation changes obviously with the addition of binders. The results of CO hydrogenation. TPR, Mossbauer spectra CI0TPF, CO/H2-TPSR and C2H4/H2-TPSR are employed to investigate the effects of various binders on the physical-chemical states and catalytic behaviors of K-Fe-MnO/Si-2 catalyst to produce light olefins via syngas, TiO2 can promote the reduction of Fe and strengthen the adsorption of CO resulting in raising olefin selectivity. Other binders such as Al2O3, SiO2, MgO, once added into the catalyst, may cause formation of inorganic salts between FeO and Binders leading to a decrease of Fe reduction and a loss of olefin selectivity for CO hydrogenation. Especially, For K-Fe-MnO/Si-2 catalyst with Al2O3 binder directly, the strong secondary reactions of ethylene during CO hydrogenation cause a very poor light olefin selectivity, which will be improved greatly by modifying Al2O3.