酯交换法合成碳酸二苯酯用氧化铅－氧化锌催化剂的研究

 制备了一种用于苯酚与碳酸二甲酯酯交换合成碳酸二苯酯的新型氧化铅－氧化锌多相催化剂．研究了制备方法、焙烧温度、不同母体和母体配比对催化剂催化性能的影响．应用XRD，TPR和原子吸收光谱对催化剂结构进行了表征，发现Pb3O4是主活性物相，ZnO为助催化剂，并以非晶态或微晶态存在于催化剂体系中．当焙烧温度为500℃，n（Pb）／n（Zn）≈2时，催化剂的活性最高，碳酸二苯酯产率可达45．6％．考察了催化剂的重复使用效果，并对失活原因进行了探讨．     

Preparation of Layer Structure-Controlled Ru-Sn-Al2O3 Catalysts and Their Reactivity

In order to achieve functional group selective hydrogenation, the layer structure of Ru-Sn-Al2O3 catalysts was controlled by using sol-gel, powder impregnation and combined sol-gel impregnation methods. The properties of the catalysts and effectiveness in hydrogenation of dimethyl terephthalate were examined. The surface Sn contents of the catalysts characterized by X-ray photoelectron spectroscopy depended on the preparation method, in spite of almost the same bulk Ru and Sn compositions measured by X-ray fluorescence analyses. TPR and CO adsorption of the catalysts also depended on the preparation method. With regard to the conversion rate of dimethyl terephthalate and the rate of product conversion from methyl 4-hydroxy methylbenzoate to p-xylene via methyl p-toluate, Ru impregnation catalysts had higher rates than the other catalysts.     

Novel type of heterogenized CuCl2 catalytic systems for oxidative carbonylation of methanol

A novel type of heterogenized CuCl₂ catalysts was designed for the oxidative carbonylation of methanol to dimethyl carbonate (DMC) taking account of the plausible reaction mechanism and intermediates. To prevent severe corrosion of the reaction equipment materials due to Cl^– while keeping the catalytic activity of the homogeneous CuCl₂ catalyst, we adopted, as supports (or ligands) of CuCl₂, four polymers, bearing a 2,2-bipyridine (bpy) or pyridine (py) unit, namely, poly(2,2-bipyridine-5,5-diyl) (Pbpy), poly(pyridine-2,5-diyl) (Ppy), poly(N,N-bisphenylene-2,2-bipyridine-4,4-dicarboxylic amide) (Bpya), and poly(4-methyl-4-vinyl-2,2-bipyridine) (Pvbpy), together with one chelate compound, 8-quinolinol. The catalytic activity, stability of heterogenized CuCl₂ and their corrosivities to stainless steels were examined in the liquid-phase reaction of the oxidative carbonylation of methanol. These polymer-supported catalysts showed considerable catalytic activity and stability for the DMC synthesis. In particular, the Pbpy-CuCl₂ and Ppy-CuCl₂ catalysts exhibited high DMC yields and selectivity comparable to those of the homogeneous CuCl₂ catalyst. This high activity appears to be associated with the presence of the -conjugated system in the polymers, which affect the redox reactions of Cu involved in the catalytic reaction. All of the polymer-supported CuCl₂ catalysts could be easily recycled after filtration, and the initial catalytic activity was maintained after three times of use. The corrosive characters of the catalysts were closely related to CuCl₂ leaching from the supports, which reflects the ability of supports to coordinate Cu. These experimental results suggest that both the electronic structure and the coordination ability of the polymer supports are key factors for the development of an effective catalytic system.     

共沉淀浸渍法制备由合成气直接合成二甲醚的Cu-Mn催化剂

采用共沉淀浸渍法,制备了直接合成二甲醚的Cu-Mn-Zn催化剂,通过对组成成分及其配比的研究,发现Cu含量一定的条件下,n(Zn)/n(Mn)摩尔比对催化剂性能有较大的影响,当n(Zn)/n(Mn)=1/3～1/2时,催化剂对CO的转化率和对二甲醚的选择性达到最佳,分别为53.6%和63.5%；如锰添加比例过大,对催化剂催化合成二甲醚有微弱抑制；添加锌比例过大,会大大降低CO的转化率。载体Y分子筛的含量对催化剂性能也有影响,用量过大将降低催化剂的活性和对二甲醚的选择性,当其含量为33%时,催化剂上CO转化率和选择性可分别达到66%和68%,且催化剂活性随分子筛含量减少不再有明显的变化。     

氟烷基化C_(60)与四（N，N-二甲基）氨基乙烯电荷转移复合物磁性的EPR研究

变温ERP研究揭示氟烷基化富勒烯C_(60)(R_f)_n与四(N,N-二甲基)氨基乙烯 (TDAE)间稳定的电荷转移络合物TDAE-C_(60)(R_f)_n的居里温度高达190K[R_f = C_3F_7，H（CF_2）_4]。而非氟烷基化络合物TDAE-C_(60)的相应值仅为16.1K。 这种铁磁性可能是络合物分子中氟烷基化富勒烯多价阴离子基在相应居里温度下具 有某种有序排列的缘故。     

Zur Synthese von fungizid wirksamen Isocamphanderivaten: Synthesen in der Isocamphanreihe, 34. Mitt.

Summary Some esters of isocamphenilanic acid (4) have been prepared and tested for their fungicidal and insecticidal activity. Esters of various acids with isocamphanyl ethylalcohol (5) have also been synthesized and included in the fungicidal/acaricidal/insecticidal screening programme. All esters bear a geminal dimethyl group at C-3 of the bicyclus which is important because of its shielding effect.

     

Catalytic Oxidation of Dimethyl Ether to Dimethoxymethane over Cs Modified HaPW12O40/SiO2 Catalysts

The attractive utilization route for one-step catalytic oxidation of dimethyl ether to dimethoxymethane was successfully carried out over the H3PW12O40（40%）/SiO2 catalyst, modified by Cs, K, Ni, and V. The Cs modification of H3PW12O40（40%）/SiO2 gave the most promising result of 20% dimethyl ether conversion and 34.8% dimethoxymethane selectivity. Dimethoxymethane could be synthe- sized via methoxy groups decomposed from dimethyl ether through the synergistic effect between the acid sites and the redox sites of Cs modified H3PW12O40（40%）/SiO2.     

2-氨基-4, 6-二甲基嘧啶与锌盐配合物的制备及生成焓测定

Thepyrimidinesasaclassareknowntopossessextraordinarybiologicalpropertiesthataregenerallydistinguishedqualitativelybytheirapplicationsinpesticide,herbicide,bactericide,andmedicineinter-mediates犤1犦.Asurveyoftheseapplicationsandanum-beroftherelatedvariationsthataredevelopedrecent-ly,suchastheextraordinaryeffectiveherbicideofsulfonylsulfourea,revealsthebroadbiologicalimpor-tancejustbecauseofthewideoccurrenceofpyrimi-dinesringsystemsinthesemolecules犤2犦.Ithasbeenshownthatthemedicineintermediates…     

高稳定性CaO-ZrO2固体碱催化剂的表征和催化性能

用共沉淀法经高温焙烧制备了CaO摩尔分数从10%至50%的CaO-ZrO₂系列催化剂, 将其应用于碳酸丙烯酯和甲醇酯交换合成碳酸二甲酯过程, 并通过XRD, FT-IR, BET, ICP, CO₂-TPD, XPS等表征手段研究了催化剂的物性及其催化性能随组成变化的的规律. 结果表明, 当CaO摩尔分数高于30%时, 表面出现游离的CaO, 虽然具有强碱性和高活性, 但是稳定性差; 而当CaO摩尔分数低于30%时, Ca^2＋进入ZrO₂晶格, CaO与ZrO₂形成连续固溶体, 并且随着CaO含量的增加, 晶格氧的电荷密度增加, 催化剂的碱性增强, 使得CaO-ZrO₂催化剂在碳酸丙烯酯和甲醇酯交换合成碳酸二甲酯过程中获得了高活性和高稳定性.     

气相色谱法测定阳离子表面活性剂合成体系中脂肪烷基二甲基叔胺

选用HP-NINOWax毛细管色谱柱及氢火焰离子化检测器（FID），采用程序升温，建立了4种脂肪烷基二甲基叔胺的分析方法。结果表明，4种脂肪烷基二甲基叔胺质量浓度在0.005~1.0 g/L范围内，其峰面积与质量浓度有良好的线性关系，相关系数（R²）在0.9996以上。检出限（LODs，信噪比为3）在0.001~0.002 g/L之间，定量限（LOQs，信噪比为10）在0.003~0.005 g/L之间，回收率在90%~130%之间，相对标准偏差为1.3%~6.9%（n=6）。方法的线性范围宽、回收率高、选择性好，可用于叔胺的产品质量分析及生产过程控制分析。利用该方法对阳离子表面活性剂合成反应中十六烷基二甲基叔胺进行监测，结果很好地符合双分子亲核取代反应。该方法比滴定分析法更快速、精确，与液相色谱法相比，不需要进行柱前衍生或者使用色谱-质谱联用仪器。