超细非晶态NiCoB合金催化剂的制备及其对大豆油加氢活性研究

对大豆油、菜籽油等植物油的选择性加氢和深加工己成为加氢领域需要迫切解决的问题,新型催化剂的研发是油脂氢化的关键。     

植物油中脂肪酸不同定量方法的比较分析

比较峰面积归一化法与标准曲线法两种方法分析植物油中脂肪酸百分比含量的差异。利用气相色谱-质谱联用仪(GC-MS)检测10种市售食用植物油中的8种主要脂肪酸,峰面积归一化法和标准曲线法计算脂肪酸的百分比含量。结果表明,标准曲线法与峰面积归一化法相比,肉豆蔻酸、棕榈酸、十七烷酸、硬脂酸和棕榈油酸所占的百分比升高,而油酸、亚油酸和亚麻酸比例降低;饱和脂肪酸比例升高,不饱和脂肪酸百分比降低。利用峰面积归一化法计算植物油中脂肪酸百分比时,降低了饱和脂肪酸比例,升高了不饱和脂肪酸比例,可能对健康有潜在的不利影响。建议使用标准曲线法计算不同植物油中脂肪酸的百分比。     

铂催化α-酮酸酯不对称氢化反应的研究进展

铂催化α-酮酸酯不对称氢化反应是合成手性α-羟基酯的重要方法之一.综述了近年来铂催化α-酮酸酯不对称氢化多相反应的研究进展,重点讨论了修饰型铂催化剂、负载型铂催化剂、纳米簇和胶体铂催化剂等不同种类铂催化剂对不对称氢化反应的影响,并对可能的反应机理进行了讨论.     

油脂选择性氢化的进展

一、油脂氢化的意义及氢化反应机理 1.油脂氢化的意义油脂是人体三大营养要素之一,也是某些精细化工产品的原料。按联合国统计,1979年全世界总计生产起酥油287万吨、人造奶油704万吨,而该年总计食用植物油产量为3010万吨,故氢化油占总食用植物油的28％。在国     

油脂氢化

本文在简要介绍油脂组成和结构的基础上说明了油脂氢化的目的与要求。着重叙述了油脂氢化反应的机理、“油脂氢化选择性”的概念的发展、以及各种氢化反应条件对油脂氢化速率及选择性的影响。进一步说明催化剂作用原理在于降低氢化反应的活化能。最后指出我国当前油脂氢化领域研究的一个热点是食用油氢化催化剂的研制,可望不久的将来即会有所突破。     

痕量动物油和植物油的区分检验研究

采用碱催化甲酯化的前处理方法,应用气相色谱-质谱联用技术对动物油和植物油的区分检验进行了研究。实验检出了6种主要脂肪酸:肉豆蔻酸、棕榈油酸、棕榈酸、亚油酸、油酸、硬脂酸。分析了动物油与植物油在成分及相对含量上的差异,并且找出了动物油和植物油在不饱和度上的差别。根据动物油与植物油的差异点,可以对动物油和植物油进行区分。     

改性Pd/C催化氢化蒎烯的研究

报道了Pd/C催化剂用于蒎烯氢化制蒎烷的研究结果 ,得到了氢化反应的适宜条件。重点考察了修饰剂对催化剂活性和选择性的影响。     

气相色谱法与麻油纯度试验法在芝麻油掺伪鉴定中的应用

用气相色谱法和麻油纯度试验法对芝麻油掺伪情况进行分析。用气相色谱法分析脂肪酸组成,测定植物油中的主要脂肪酸,来确定是何种油或掺入其它何种植物油;麻油纯度试验法用于定量。两者可结合起来使用。     

铱-氮膦配体催化剂在非官能化烯烃不对称氢化中的研究

非官能化烯烃的不对称氢化反应一直是烯烃加氢领域的难点。研究表明,铱-氮膦配体催化剂对此类反应具有很好的催化活性和选择性,因而受到国内外众多学者的关注。本文对近年来利用铱-氮膦配体催化剂对非官能化烯烃进行不对称氢化的研究进展进行了综述,介绍了不对称氢化的历程及背景,着重讨论了铱-氮膦配体催化剂的催化机理（Ir^Ⅲ-Ir^Ⅴ催化循环机理、Ir^Ⅰ-Ir^Ⅲ催化循环机理）、铱催化剂的组成以及催化性能的比较,并对铱催化剂在不对称氢化中的发展前景作了展望。     

含氨基酸侧链的有机硅高分子催化剂（ⅩⅧ）：—聚γ—（甘—谷氨酰胺基）丙基硅氧烷钯催化剂的合成及加氢活性

合成了不同N／Pd摩尔比的聚γ-（甘－谷氨酰胺基）丙基硅氧烷钯催化剂，表征了它们的结构，加氢实验表明，这种催化剂有很高的催化活性，对环戊二烯氢化分两步完成，对1，5－己二烯氢化则同时进行，讨论了溶剂、N／Pd摩尔比对催化剂活性的影响。     

Raney镍催化松香加氢反应的机理

催化加氢;反应机理;氢化松香;Raney镍催化松香加氢反应的机理     

Silver and palladium nanoparticles-containing products of the low-temperature wave conversion of an energetic material: Catalytic activity in piperylene hydrogenation

The hydrogenation of 1,3-pentadiene into pentenes over the commercial 0.5% Pd/Al₂O₃ catalyst and over a new catalyst containing 1.0% Pd and 3.7% Ag (μ-catalyst) has been investigated. The new catalyst has been prepared via the flameless wave conversion of cyclotrimethylenetrinitramine in a porous composite. The catalytic properties of the new composite in the hydrogenation reaction depend on the hydrogen/1,3-pentadiene ratio and on the catalyst activation temperature. The reaction conditions for selective 1,3-pentadiene hydrogenation have been optimized. The pentenes yield as a function of temperature passes through a maximum at any H₂/C₅H₈ ratio between 1 and 2. The 2-pentene/1-pentene ratio in the reaction products increases as the temperature is raised.     

（RCp）2TiCl2—Pr^iMgBr存在下二苯乙炔的选择性加氢

最近我们发现了在催化量(RCp)_2TjCl_2-Pr~iMgBr存在和常温常压下二苯乙炔的加氢反应。该反应以H_2为还原剂,经顺、反式二苯乙烯可定量地得到二苯乙烷。它比以格氏试剂为还原剂的钛氢化反应更具优越性。     

Mild Hydrogenation of Amides to Amines over a Platinum‐Vanadium Bimetallic Catalyst

Hydrogenation of amides to amines is an important reaction, but the need for high temperatures and H₂ pressures is a problem. Catalysts that are effective under mild reaction conditions, that is, lower than 30 bar H₂ and 70 °C, have not yet been reported. Here, the mild hydrogenation of amides was achieved for the first time by using a Pt‐V bimetallic catalyst. Amide hydrogenation, at either 1 bar H₂ at 70 °C or 5 bar H₂ at room temperature was achieved using the bimetallic catalyst. The mild reaction conditions enable highly selective hydrogenation of various amides to the corresponding amines, while inhibiting arene hydrogenation. Catalyst characterization showed that the origin of the catalytic activity for the bimetallic catalyst is the oxophilic V‐decorated Pt nanoparticles, which are 2 nm in diameter.     

非晶态超微粒子镍合金催化剂的研究──Ⅱ．Ni－B催化剂对苯加氢反应动力学的研究

非晶态超微粒子镍合金催化剂的研究──Ⅱ．Ｎｉ－Ｂ催化剂对苯加氢反应动力学的研究李同信，张秀峰，李合秋（中国科学院大连化学物理研究所，大连１１６０２３）靳常德，蒋育林，崔建彤，王大庆（大连理工大学化工学院，大连１１６０１１）关键词非晶态超微粒子，镍基合...     

Selective hydrogenation of cinnamaldehyde over carbon nanotube supported pd-ru catalyst

Summary Carbon nanotube supported Pd, Ru and Pd-Ru catalysts have been prepared and tested with the hydrogenation of cinnamaldehyde as a probe reaction. It has been found that the cinnamaldehyde conversion and the selectivity towards the hydrogenation of C=O bond over Pd-Ru/PCNT catalyst could reach 56.6% and 79.1%, respectively, at 120^oC and 5.0 MPa, which is better than Pd/PCNT and Ru/PCNT catalysts under the same reaction conditions. It is assumed that the better performance of Pd-Ru/PCNT catalyst for cinnamaldehyde hydrogenation may be due to the synergic effect of Pd and Ru metals or the promoting effect of Ru metal.     

SELECTIVE HYDROGENATION OF MALEIC ANHYDRIDE TO |?-BUTYROLACTONE USING HOMOGENEOUS Ru/PPh3 CATALYST SYSTEM

The hydrogenation of maleic anhydride (MA) using various homogeneous transition metal complex catalysts has been studied. It is revealed that RuCl3.3H2O is the most active catalyst and triphenylphosphineis the optimum ligand for the preparation of butyrolactone. The effects of catalyst concentration, mole ratio of triphenylphosphine to Ru, temperature and hydrogen pressure on the hydrogenation have been investigated. By changing reaction conditions, -butyolactone could be produced selectively. A possible reaction mechanism is proposed.     

水溶性钯配合物催化柠檬醛的选择加氢反应研究 Ⅰ.反应条件的影响

研究了在水／有机物两相体系中水溶性钯－膦配合物催化柠檬醛的加氢反应．考察了反应温度、氢气压力、底物和催化剂浓度、反应时间、水相ｐＨ值等对该反应的影响，并与几种柠檬醛衍生物的加氢结果进行了比较．发现仅用蒸馏水作水相，则主要产物是二氢香茅醛（＞９３％）；而水相中加入Ｎａ２ＣＯ３后，则主要产物为香茅醛（９７％），且加氢速度比同样条件下使用Ｐｄ／Ｃ催化剂快得多．     

Kinetics of the liquid-phase catalytic hydrogenation of chlorine-containing aromatic nitro compounds in the presence of pyridine

We have analyzed experimental kinetic data for nitro compound consumption, for the formation of the corresponding amino product, and for the accumulation of intermediate products and by-products in the hydrogenation of chlorine-containing aromatic nitro compounds. The reaction has been carried out under static conditions over a platinum catalyst on a porous support in the presence of pyridine. The effect of the admixture on different hydrogenation steps of a chlorine-containing aromatic nitro compound has been quantitatively interpreted.     

NMR imaging of the distribution of the liquid phase in a catalyst pellet during alpha-methylstyrene evaporation accompanied by its vapor-phase hydrogenation

This communication reports the first application of NMR imaging to study the progress of a multiphase heterogeneous catalytic reaction in situ. Various stationary regimes of alpha-methylstyrene (AMS) hydrogenation on a single Pt/gamma-Al2O3 catalyst pellet have been investigated. The two-dimensional maps of the liquid-phase distribution within the pellet have been obtained in the course of the catalytic reaction, with the pellet temperature rising up to 185 degrees C. The large liquid-phase concentration gradients have been shown to exist under conditions of liquid AMS evaporation accompanied by its vapor-phase hydrogenation. It has been demonstrated that despite a substantial broadening of the NMR lines of liquids permeating porous solids the quantification of the relative amounts of AMS and the major reaction product cumene with spatial resolution across the pellet is feasible.