Hydrogenation of oleic acid to 9-octadecen-1-ol with rhenium-tin catalyst

A new supported bimetallic catalyst, rhenium-tin, is able to reduce oleic acid to 9-octadecen-1-ol (cis andtrans isomers) with appreciable yield under mild hydrogenation conditions. This paper reports investigations on the effects of catalyst preparation methods, types of support, catalyst raw materials, mole ratio of the metals, activation and reaction conditions on the activity and selectivity of the catalyst. Catalyst derived from the combination of ammonium perrhenate and stannic chloride on alumina gave the best performance, and the presence of tin in the catalyst is essential for the preservation of the olefinic bond of the oleic acid during hydrogenation.     

Hydrogenation of 9-octadecenoic acid by Ru−Sn−Al2O3 catalysts: Effects of catalyst preparation method

Evaluation of the method of preparation and the sequence of metal incorporation onto the catalyst showed that they had profound effects on the catalytic behavior of Ru−Sn−Al₂O₃ catalysts used in the selective hydrogenation of oleic acid to 9-octadecen-1-ol. When Ru was loaded first onto the support and then followed by Sn, the catalyst had lower activity but greater ability to preserve the unsaturated bond. On the other hand, when the sequence of loading was reversed, the behavior of the catalyst changed correspondingly, i.e., the catalyst showed higher activity but poorer ability to protect the unsaturated bond. The metal particles incorporatedvia the sol-gel method were finely and evenly distributed on the support. As such, they were more readily shielded by the second metal particles that were subsequently incorporatedvia the impregnation process. When both metals were loadedvia the sol-gel process, the best result was obtained with superior performance in activity, as well as selectivity in the preservation of double bond.     

Selective hydrogenation of oleic acid to fatty alcohols using Rh-Sn-B/TiO2 catalysts: Influence of Sn content

The influence of the catalyst Sn content on the production of fatty alcohol from oleic acid by selective hydrogenation was studied using Rh-Sn-B catalysts supported on TiO₂. The crystal phase of the support was analyzed by X-ray diffraction (XRD), the reduction state of the metal phase by temperature-programmed reduction (TPR), and the electronic state of surface species by X-ray photoelectron spectroscopy (XPS). The metal activity was evaluated by the dehydrogenation of cyclohexane. It was found that the increase in Sn content leads to a proportional drop in the catalytic activity, which could be related to a metallic interaction between Rh and Sn, as shown by TPR. Oxide and metallic Sn, as well as Rh⁰ and Rh³⁺, were found by XPS on the catalyst surface. Metallic Rh was, however, found in higher concentration than oxidized Rh in all cases. The yield to fatty alcohols increased with Sn content, and its maximum value for oleyl and stearyl alcohol was 96%. Furthermore, a higher yield (88.3%) was obtained out of unsaturated fatty alcohol (oleyl alcohol), which has proved to be more valuable than saturated alcohol. This was attributed to an adequate Rh/Sn ratio, which modulates the hydrogenating activity of Rh and makes the metal function more selective for hydrogenation of the carbonyl group. The influence of the support on the catalyst performance decreases as the Sn content increases. The support has a practically negligible influence on the catalyst activity for 4–5 wt.% of Sn content.     

环戊二烯选择加氢制环戊烯

用Pd催化剂在固定床反应器中进行了环戊二烯选择加氢制备环戊烯研究;确定了第一段加氢催化剂采用Pd含量为0．5（wt）％载体为γ-Al2O3催化剂,第二段加氢催化剂为钯含量为0．3（wt）％载体为γ-Al2O3催化剂。第一段氢烃摩尔比为2—3,反应压力为1．2MPa,空速2～4h～,温度55—60℃,第二段氢烃摩尔比为3．5～4,温度80～85℃时,环戊二烯的转化率达99．5％,环戊烯的选择性在90％以上。     

1,2-环氧丁烷选择性加氢制正丁醇

考察了金属催化剂与负载催化剂对1,2-环氧丁烷的选择加氢活性。结果表明,以中性或弱碱性的硅胶为载体、钴为加氢活性金属和氧化镁为助剂的负载型催化剂具有良好选择性加氢效果,1,2-环氧丁烷加氢后转化率达到92.37%,正丁醇选择性为89.29%,仲丁醇选择性为3.19%,正丁烷选择性为1.5%,醇醚等副产物的选择性为5.32%。     

二氯乙酸选择性加氢脱氯制备高纯氯乙酸

以Pd/C为催化剂,通过固定床反应器对含氯乙酸、二氯乙酸以及乙酸的氯化液进行选择性催化加氢脱氯研究,使氯化液中的大部分或全部二氯乙酸转化为一氯乙酸或乙酸。考察催化剂制备条件对催化性能的影响,结果表明,在Pd负载质量分数0.9%、浸渍液浓度4.5 g·L-1和浸渍温度20℃条件下制备的催化剂,催化活性和产物选择性最佳,运行时间超过1 500 h活性未出现明显衰减。     

四丁基溴化铵催化合成2-甲基-2-苯基丙醇

在相转移催化剂四丁基溴化铵存在下,以氯代叔丁基苯和氢氧化钠为原料合成2-甲基-2-苯基丙醇。分别研究了反应温度、反应时间、氢氧化钠浓度、催化剂用量等条件对合成反应的影响,优化了工艺条件:反应温度70℃,反应时间4 h,氢氧化钠浓度20%(m/m),催化剂用量3%(n/n,以氯代叔丁基苯计),收率68.7%。     

制备条件对肉桂醛选择加氢Co-Fe/硅藻土催化剂的影响

对肉桂醛选择加氢制肉桂醇的Co-Fe/硅藻土催化剂的制备条件进行了研究,并对超声波作用下制备的催化剂的催化性能优化进行了探讨。通过催化反应评价和SEM、XRD及正电子寿命谱的测定等表征,结果表明,焙烧温度和还原温度对Co-Fe/硅藻土催化剂的催化性能影响较大,不但可改变催化剂的晶体结构,也能对载体及载体与催化剂的作用产生影响。最佳焙烧温度为673 K,还原温度为723 K。制备过程中引入超声技术,使催化剂的晶形细化并在载体上更好铺展,有利于改善和提高催化性能。     

Chemical conversion of 9-tetradecen-1-ol acetates to 3,13-octadecadien-1-ol acetates,sex attractants for male clearwing moths (Lepidoptera: Sesiidae)

Males of many species of clearwing moths are attracted by one of the geometrical isomers of 3,13-octadecadien-1-ol acetate or by a mixture of isomers. The synthesis of (E,Z)-, (E,E)-, and (Z,E)-3,13-octadecadien-1-ol acetate is described starting with the (Z)- and (E)-9-tetraceden-1-ol acetates, which are commercially obtainable.     

YN-1型催化剂在裂解汽油C_9~+选择加氢装置的工业应用

介绍了YN-1型镍系催化剂在新疆独山子天利实业总公司裂解汽油C+9馏分选择加氢装置的工业应用。结果表明,YN-1型镍系催化剂用于胶质含量100 mg·(100m L)-1和溴价95 g Br·(100g)-1的C+9馏分原料选择加氢,能够适应超过90℃的反应温升,并表现出低温活性高、稳定性好和容胶量大的优点。     

多不饱和脂肪酸及其酯的选择性加氢研究进展

尽管部分加氢是提高多不饱和脂肪酸及其酯性能的一种有效方式,但加氢过程中反式异构体的生成会影响油脂的品质,因此,对油脂加氢反应中如何减少反式异构体生成的研究具有一定的意义。首先,介绍了多不饱和脂肪酸及其酯加氢机理及反式异构体生成的原理。然后,综述了加氢方式、加氢催化剂(包括活性组分、助剂、载体及催化剂制备方法)对反式异构体生成影响的研究新进展。最后,对影响反式异构体生成的规律进行总结,进而提出了多不饱和脂肪酸及其酯加氢过程中以减少反式异构体生成为目的的措施。     

Preparation of Ni/SiO2 catalyst in ionic liquids for hydrogenation

A series of silica supported nickel catalysts were prepared from nickel nitrate and tetraethyl orthosilicate by the sol-gel method with the imidazolium type ionic liquids as solvents. The catalysts were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Their catalytic performances for the selective hydrogenation of cinnamaldehyde to hydrocinnamaldehyde were investigated. The results show that the Ni/SiO₂ catalyst prepared with 1-(2-hydroxyethyl)-3-methylimidazole tetrafluoroborate ionic liquid as solvent exhibits the highest catalytic activity for the reaction. Under the optimal conditions of catalyst dosage (based on the mass of cinnamaldehyde used) 10%, reaction pressure 2 MPa, temperature 373 K and reaction time 2 h, the conversion of cinnamaldehyde and the selectivity to hydrocinnamaldehyde can reach 97.6% and 98.8%, respectively. __________ Translated from Petrochemical Technology, 2007, 36(1): 9–14 [译自:石油化工]     

Kinetics of catalytic esterification of propan-1-ol with propanoic acid using cation-exchange resin

The kinetics of liquid phase esterification of propan-1-ol with propanoic acid catalysed by Dowex-50W cation-exchange resin in the H⁺ form have been studied in a batch reactor. The effects of catalyst concentrations, mol ratios and temperatures on the conversion were studied. An empirical correlation relating the specific reaction rate constant in terms of these variables has been developed, and a mechanism proposed on the lines of the Langmuir-Hinshelwood model. The effect of different catalysts on the conversion is compared.     

1,4-丁炔二醇选择性加氢催化剂：Pd/ZrO2及其碱金属改性

本文以Zr(OH)4焙烧所得ZrO2为载体,采用等体积浸渍法制备了负载型Pd/ZrO2和碱金属改性的Pd/M/ZrO2催化剂,通过BET、XRD、CO2-TPD、XPS和TEM对催化剂结构和性质进行了表征,并对其在1,4-丁炔二醇（BYD）选择性加氢制1,4-丁烯二醇（BED）反应中的活性、选择性和稳定性进行了研究,考察了反应气氛、碱金属改性等对其活性和稳定性的影响。结果表明1.0% Pd/ZrO2在50 ℃,2.40 MPa H2下,能够催化1,4-丁炔二醇选择性加氢生成1,4-丁烯二醇,有较高的催化活性〔0.048 molBYD/(gPd·s)〕,在BYD完全转化的条件下,BED选择性为91.2%。反应体系中引入氨,能够显著抑制催化剂加氢活性,提高BED选择性。在BYD接近完全转化时,BED选择性可达95.6%。向ZrO2载体中引入少量的碱金属（Li、Na、K、Rb、Cs）能够提高BED选择性,其中Rb的影响最为显著,BED选择性可达94.1%。     

Selective hydrogenation of ethyl phenylacetate to 2-phenylethanol: a convenient catalyst preparation method

A ruthenium-tin-alumina catalyst, prepared by a combination of kneading and impregnation methods, which we have named the combination method, was able to selectively hydrogenate ethyl phenylacetate to 2-phenylethanol; tin oxide was used as a chloride-free tin source. For this combination catalyst, the optimum atomic ratio for Ru: Sn was found to be 1 4. X-ray diffraction measurements showed the presence of tin particles. It appeared that the number of the tin particles had a large effect on the hydrogenation of C=O groups. However, the catalyst prepared with ruthenium oxide had a low activity, possibly owing to the ruthenium metal or ruthenium-tin alloy, which was formed and which obstructed the reaction.     

凹凸棒土负载Pt催化剂的氯代硝基苯选择性加氢性能

以3 mol·L-1的HCl酸化凹凸棒土为载体,200℃还原制备负载型纳米Pt催化剂,并应用于氯代硝基苯选择加氢反应。在反应温度60℃和反应压力2.0 MPa条件下,催化剂显示出优异的加氢活性和选择性,在氯代硝基苯完全转化情况下,氯代苯胺选择性达100%,制备的催化剂具有很高的金属分散度,Pt纳米粒子粒径约2 nm,凹凸棒土载体对提高Pt分散度发挥了关键的作用,高分散纳米Pt粒子显著提高催化剂的加氢活性与氯代苯胺选择性,完全抑制了脱氯现象。     

The kinetics of the esterification reaction between castor oil and oleic acid

In this study, esterification of castor oil with oleic acid was investigated in view of the reaction kinetics under various conditions. Potassium hydroxide,p-toluenesulfonic acid and tin chloride (SnCl₂2H₂O) were used as catalysts. Reaction was carried out at 200°C, 225°C and 250° C by using equivalent proportions of the reactants. For tin chloride, experimental data fitted the second-order rate equation, while for the other catalysts the obtained data fitted the third-order rate equation.     

Co/TiO2-SiO2催化剂上肉桂醛选择性加氢制备肉桂醇

采用等体积浸渍法制备了系列Co/TiO₂-SiO₂催化剂,用于肉桂醛选择性加氢制备肉桂醇反应体系。系统考察了钴含量、焙烧温度、还原温度、稀土助剂等参数变化对钴催化剂选择性加氢性能的影响。结果表明,钴催化剂的活性和选择性与其表面钴的晶粒度有一定关系,较大尺寸的钴物种对肉桂醛加氢有利。当Co含量为15%、焙烧温度和还原温度均为823 K时,催化剂表现出良好的加氢性能。稀土助剂La和Ce的引入能改善Co /TiO₂-SiO₂催化剂表面活性组分钴的分散度,提高了钴催化剂的加氢性能。     

丙二烯磷酸选择加氢制丙烯磷酸催化剂

磷霉素是一种新型的广谱抗菌药,它的合成一般包括六步反应,其中由丙二烯磷酸制备丙烯磷酸是以Pd/C作为催化剂.笔者利用浸渍法制备了一系列活性组分质量分数不同的催化剂,结果发现活性组分负载量越高,催化剂的活性越好,因为组分质量分数高,金属在载体表面能够形成一定均匀大小的晶粒,影响到活性的大小;考察了不同的载体活性炭、MCM-41、γ-Al2O3和HZSM-5,结果发现活性炭作为载体的催化剂性能好,不同载体与活性组分形成的晶型不同,从而影响其加氢的活性;考察了钌和钯两种活性组分,结果发现钯比钌的性能好,可能是由于金属钌在载体活性炭上的分布较弥散,不能形成较大的晶粒,即以非晶态存在,活性低.     

负载型催化剂上丙烷选择氧化制丙烯酸的研究

制备了负载型氧化物催化剂AgyBi1-x-yV1-3xMo3xΦxO4/Al2O3,并用于丙烷选择氧化制丙烯酸反应。考察了反应温度、负载量、掺杂离子对催化剂反应性能的影响。研究发现,w(AgyBi1-x-yV1-3xMo3xΦxO4)=40%、y=0 01的负载型催化剂在400℃下反应时,丙烷转化率为20 2%,丙烯酸选择性为8 6%。同时,对非负载型催化剂AgyBi1-x-yV1-3xMo3xΦxO4进行了对比研究和表征,结果表明,负载Al2O3载体能改善催化剂的表面结构,提高催化剂的反应性能。