低温加氢催化剂的设计: 理论与实践

简要总结了我们在C=C及C=O双键低温加氢双金属催化剂方面的最新研究成果. 首先, 我们以环己烯加氢为探针反应, 证明了平行使用多种研究手段的重要性, 包括单晶表面的基础研究与DFT计算, 多晶表面的合成与表征, 负载型催化剂的制备与性能测试等. 其次, 总结了双金属催化剂在其他加氢反应, 如丙烯醛C=O双键的选择性加氢, 苯的低温加氢, 以及乙炔的选择性加氢等反应中的应用. 最后, 讨论了利用金属碳化物代替贵金属Pt以减少双金属催化剂中Pt用量的可能性.     

金属—半导体氧化物催化剂

本文重点研究了TiO2、ZnO、SnO2等半导体氧化物以及以此为担体的担载型金属－半导体组合催化材料；采用电导、TPD、TPSR等方法考察了这类材料和典型的电子受体和电子给体反应分子间的电子和物种和交换，并研究了金属－半导体组合界面上的电子传递特性。根据测试结果及催化反应的例证说明，在金属－半导体氧化物组合材料中金属可以活化反应分子，沟通电荷物种的交换渠道，而氧化物类似于“电子储库”。二者协同作用使组合体系具有良好的氧化还原化学感应和催化作用。     

SO^2—4／ZrO2超强酸制备方法的改进

用ＢＥＴ、ＸＲＤ、流动指法剂法、化学分析、低温正丁烷异构化反应等手段研究了制备条件对ＺｒＯ２前驱体和ＳＯ＾２－４／ＺｒＯ２超强酸性能的影响。实验结果表明，采用不同的制备条件，ＺｒＯ２前驱体的比表面可相差１．８倍，ＳＯ＾２－４／ＺｒＯ２的酸强度相差约１０００倍，ＳＯ＾２－４／ＺｒＯ２的正丁烷异构化反应活性相差约３００倍，ＺｒＯ２最高比表面可达２４５ｍ＾２／ｇ，ＳＯ＾２－４／ＺｒＯ２酸强度为Ｈ０≤－１     

氧化锌微晶的制备和形貌控制

本文在溶液体系中合成了多种形貌的氧化锌(ZnO)微晶。所得花状、雪花状、棒状、多刺球状和棱柱状氧化锌微晶用粉末X射线衍射(XRD)和扫描电镜(SEM)进行了鉴定和表征,考察了反应条件如溶剂、温度及pH值对ZnO微粒尺寸和形貌的影响,初步探讨了不同形貌ZnO微粒的生长机理。该文对制备形貌可控的氧化物具有一定的指导意义。     

(±)-3-正丁基-4-甲氧基苯酞的合成

以3-羟基苯甲酸为原料,通过中间体(±)-3-羟基-4-甲氧基苯酞合成了(±)-3-正丁基-4-甲氧基苯酞(?)。     

SDS/n－C5H11OH/n－C7H16/H2O体系中W/O－BI微乳液界面电性质

In the system of SDS/n-C5H11OH/n-C7H16/H2O with the weight ratio of SDS/n-C5H11OH/H2O system at5.0/47.5/47.5, the upper phase of the system was W/O microemulsion, and the lower phase was the bicontinuous microemulsion. When the n-heptane content was less than 1%, with the increase of the n-heptane content, the capacitance (Co, Cod) in the upper phase (W/O) dropped, the capacitance (CB1, CBld) in the lower phase (BI) raised. At the same time, the W/O-BI inteffacial potential (ΔE), capacitance (Ci), and charge-transfer current (ict) decreased.After the n-heptane content reached 1%, with the increase of the n-heptane content, ΔE, Ci and ict demonstrated no significant change.     

Cu-Ce/γ-Al2O3对硬脂酸催化水热脱氧产生烷烃的效果

利用等体积浸渍法制备Cu-Ce/γ-Al₂O₃催化剂，并在无H₂存在的条件下对硬脂酸进行催化水热液化。对催化剂进行BET比表面积分析和X射线衍射（XRD）分析可知，Cu-Ce/γ-Al₂O₃催化剂中存在CuO和CeO₂两种晶型，在300℃条件下水热反应12 h后具有更好的热稳定性。通过对硬脂酸进行水热液化实验和对生物油进行气相色谱-质谱（GC-MS）分析发现，加入Cu-Ce/γ-Al₂O₃催化剂能够获得最高的硬脂酸转化率（94.71%）和总烃产率（81.41%），水热液化脱氧效果最好。分析正烷烃的产率，结果发现硬脂酸在高温水热条件下主要发生脱羧反应。Cu-Ce/γ-Al₂O₃催化剂的加入能够同时促进反应过程中脱羧反应、加氢脱氧反应和裂化反应。此外，Cu-Ce/γ-Al₂O₃还能够促进羰基基团的脱除，有效减少产物中的醛和酮类物质。     

Synthesis of 2-Aminochromene Derivatives Catalyzed by KF／Al2O3

A series of 2-aminochromene derivatives including 2-amino-ben-zo[ h ] chromene, 2-amino-benzo [ f ] chromene and 2-amino-pyrano [3,2-h ]quinolin derivatives was synthesized from aryl-aldehyde, malononitrile or ethyl cyanoacetate and 1-naphthol or 2-naphthoi or 8-hydroxyquinoline in refluxing ethyl alcohol cat-alyzed by KF-Al2O3. The structures were confirmed by X-ray analysis.     

Michael-Addition Reaction of Malononitrile with α,β-Unsaturated Cycloketones Catalyzed by KF／Al2O3

A series of KF/Al2O3 catalyzed Michael-addition reactions between malononitrile and α,β-unsaturated cycloketones in DMF solution were studied. At room temperature, 2-cyano-3-aryl-3-(1,2,3,4-tetrahydronaphthalen-1-one-2-yl) propionitrile derivatives were synthesized by the reaction between 2-arylmethylidene-1,2,3,4-tetra-hydronaphthalen-1-one and malononitrile. However, if the temperature was increased to 80℃, 2-amino-3-cyano-4-aryl-4H-benzo[h]chromene derivatives were obtained in high yields. When the α,β-unsaturated ketones were replaced by 2,6-biarylmethylidenecyclohexanone or 2,5-biarylmethylidenecyclopentanone, another series of 2-amino-3-cyano-4H-pyran derivatives was isolated successfully. The structures of the products were confirmed by X-ray diffraction analysis.