国内油脂加氢催化剂现状及发展趋势

叙述了国内油脂加氢催化剂的研究现状,包括催化剂的制备方法和在油脂加氢方面的应用,指出油脂氢化催化剂的发展趋势是向超细及非晶态催化剂发展。     

非晶态合金催化剂的制备及其用于油脂加氢反应的研究

简述了国内油脂加氢催化剂的现状,介绍了化学还原法制备非晶态合金催化剂,及其在油脂加氢反应中的应用研究,指出了非晶态合金催化剂应用于油脂加氢反应的研究趋势.     

食用油脂加氢催化剂研究进展

对食用油脂加氢催化剂的研究现状进行了综述,并介绍了新型催化剂及催化工艺在食用油脂催化加氢上应用的优缺点。强调由单元体金属向多元体金属;多相催化剂向均相催化剂过渡是该类食用油脂氢化催化剂的发展趋势。     

油脂催化加氢催化剂的研究进展

介绍了国内外油脂加氢催化剂的研究状况及金属镍的催化原理、影响催化剂活性的因素、催化剂载体、催化剂中毒、催化剂制备方法、催化反应条件的控制等，指出开展油脂加氢催化剂研究的重要意义。     

CIM-6单元镍油脂氢化催化剂的研制

在用H2 冷等离子体处理常规Cu -Ni二元油脂加氢催化剂 ,发现一种新的、有用的催化剂表面结构和研制开发成功CIMCu -Ni二元油脂加氢催化剂及其相关技术的基础上 ,研制成了CIM - 6单元镍油脂加氢催化剂。实验结果表明 :1 CIM - 6催化剂用于豆油加氢制食用氢化油 ,其活性 (以催化剂的时空转化率计 )是SP - 7催化剂 (美国EngelhardCo.)的 4 5倍 ;用于菜油加氢制食用氢化油 ,其活性是SP - 7的 7 3倍。 2 CIM - 6的抗硫能力 (n(S) =3× 10 - 6 )是SP - 7的1 6倍。 3 CIM - 6的选择性比SP - 7略好     

加氢催化剂的制备及其再生技术研究

介绍了生产饱和天然油脂脂肪酸甲酯所用加氢催化剂的制备及再生技术。     

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。     

油脂加氢催化剂研究现状及发展趋势

本文介绍了油脂加氢催化剂的研究现状，指出氢化催化剂的发展趋势是由单元体金属向多元体金属、由贵金属向贱金属、由多相催化剂向均相催化剂过渡。     

共沉淀法制备镍基催化剂及其在油脂氢化工艺中的应用

本文研究了由共沉淀法制备的镍基催化剂对大豆色拉油的加氢反应,并考察了反应温度、压力、时间和催化剂用量等工艺条件在油脂氢化中的影响。     

油脂催化加氢转化制备第二代生物柴油研究进展

生物柴油是一种清洁的可再生能源，是应对温室效应、环境污染、能源短缺等问题最有潜力的发展方向之一。第二代生物柴油是油脂与氢气(H₂)进行加氢转化反应制得的与传统石化柴油组成类似的烃类混合物，除具有绿色环保、十六烷值高、可再生等优点外，还具有低温流动性好、含氧量低、稳定性高、热值高等特点，可与石化柴油无比例限制地混合使用。系统总结了近年来油脂催化加氢转化制备第二代生物柴油方面的研究进展，包括加氢转化机理、催化剂活性相、催化剂载体和加氢转化工艺四个方面，着重介绍高效加氢转化催化剂的设计和开发。此外，还分析了油脂催化加氢转化制备第二代生物柴油领域所面临的机遇和挑战，并对未来的发展方向进行了展望。     

Aspekte bei der Hydrierung von Fetten und Fettsäuren

Aspects of Hydrogenation of Fats and Fatty Acids Hydrogenation of fat products is of great significance, both for human and animal nutrition as well as for technical purposes. In the area of nutrition, adequate food for the increasing world population is unthinkable without utilization of all fat resources, that can be made available as food fats only after catalytic hydrogenation. In the area of technical use, a similar development is observed owing to shortage of mineral oils. Thus, fatty alcohols derived from vegetable oils and waxes can already compete in price with fully synthetic fatty alcohols derived from mineral oils. In the past 70 years of hydrogenation of fats till the present time, catalysts based on nickel have been most commonly used. In addition, small proportions of catalysts based on copper and noble metals have also been used. Homogenous catalysts have been used very recently. The present communication deals primarily with the hydrogenation of neutral fats and fatty acids using nickel catalysts. The aspects of selectivity and isomerization in the partial hydrogenation of neutral fats are discussed. In the hydrogenation of fatty acids and their derivatives, emphasis is laid on other factors, such as activity, poisoning and acid resistance of the catalyst. These factors are discussed.     

Manufacture of fatty alcohols based on natural fats and oils

The present worldwide capacity of fatty alcohols is ca. 1.0 million metric tons per year. About 60% of this capacity is based on petrochemical feedstocks, 40% on natural fats and oils. Three basic dominating commercial-scale processes are used to manufacture fatty alcohols: the Ziegler process and the Oxo synthesis starting from petrochemical feedstocks, and the high-pressure hydrogenation of natural fatty acids and esters. Basically, the high-pressure hydrogenation can be used with triglycerides, fatty acids or fatty acid esters as feedstock. The direct hydrogenation of fats and oils has not been developed to a commercial-scale process, mainly because it was not possible to prevent decomposition of the valuable byproduct glycerol. Conversion of fatty acids into fatty alcohols by catalytic hydrogenation without preesterification requires corrosion-resistant materials of construction and acid-resistant catalysts. Required reaction temperatures are higher, resulting in a higher hydrocarbon content. The majority of fatty alcohol plants based on natural fats and oils use methyl esters as feedstock. These can be made either by esterification of fatty acids or by-transesterification of triglycerides. For catalytic high-pressure hydrogenation of methyl esters to fatty alcohols, several process options have been developed. The bawic distinguishing feature is the catalyst application either in a fixed bed arrangement or suspended in the methyl ester feed.     

Hydrogenation of Edible oils

The supply and demand of edible oils and fats is briefly reviewed, and certain trends, relevant for the application of fat modification techniques, are noted. The effect of hydrogenation conditions on a number of selectivity aspects in hydrogenation with nickel catalysts is explained in terms of mass transport effects for hydrogen and triglycerides. The effect of selectivity on stability and melting behavior is also discussed. The limitations of the existing hydrogenation process with nickel are pointed out, and possible extensions by use of other catalysts, such as sulphur poisoned nickel, copper, and chromium complexes, are mentioned. Some technological aspects of the process are briefly reviewed.     

Hydrogenation of fatty acids

Catalytic hydrogenation is a vital process for both the edible fats and oil and the industrial fatty chemical industries. The similarities and differences between the fat and oil and fatty acid hydrogenations in equipment, processing conditions, and catalysts employed are of some importance since both are used in the various operations. Generally, the catalytic hydrogenation of fatty acids is carried out in corrosion-resistant equipment (316SS), whereas for fats and oils while 316SS is desirable, 304SS or even black iron surffice. The speed of hydrogenation varies radically with the content of impurities in both fat and oil and fatty acid feedstocks. Especially detrimental for both hydrogenations are soap and sulfur contaminants, proteinaceous materials left in the oils from poor refining, etc. Fatty acids from vegetable oil soapstocks are especially difficult to hydrogenate. Soybean-acidulated soapstock must usually be double-distilled for good results; cottonseed soapstocks frequently triple-distilled in order that they can be hydrogenated below iodine values of 1. Fatty acid hydrogenation effectiveness is measured by achieveing a low iodine value as fast and as economically as possible. Variables that influence hydrogenation effectiveness are reactor design, hydrogen purity, feedstock quality, catalyst activity and operating conditions.     

Computation of nickel catalyst activity in the hydrogenation of triacylglycerol oils

The development of a new method for a faster and more accurate computation of the nickel catalyst activity was studied. This catalyst is used in partial catalytic hydrogenation of vegetable oils for production of edible fats. In order to index the activity, a computer program, CATACT, was developed using FORTRAN language. This program uses 3 easily determined experimental values as input data (refractive index at 60 C, catalyst concentration and hydrogenation time). Output data are catalyst activity indexes either in word or numerical form. The hydrogenation data were gathered from a laboratory reactor under laboratory conditions. Using these data, we computed the activity of Ni catalysts which have been reused in oil hydrogenation under industrial conditions. The classical method of determining such activity by evaluating the melting point is, in view of the very low activity of such catalysts, inadequate to provide sufficient information for easy interpretation.     

Mehrmalige Verwendung von Nickel-Katalysator im Fischöl-Hydrierungsprozeß

Repeated Use of Nickel Catalysts in the Process of Hydrogenation of Fish Oils The use of nickel catalysts in the industrial hydrogenation of fats and oils is made by two different methods. In some plants nickel catalyst is used only once, taking care that as far as possible least amounts of catalyst are used. In other plants, the filtered catalyst is reused. With the example of hydrogenation of fish oil the technical as well as economical advantages and disadvantages of the individual techniques of hydrogenation are investigated. Optimization of the cycle involving reuse of the catalyst can be of economic advantage, as compared to a single use of the catalyst. It was also found that products having a better consistency (harder fats) are obtained by reuse of the filtered catalyst mass. A further advantage of this technique is a better reproducibility of the product properties.     

Low trans hydrogenation of edible oils

Hydrogenation of edible oils is an important process in the food industry to produce fats and oils with desirable melting properties and an improved shelf life. However, beside the desired hydrogenation reaction trans fatty acids are formed as well. As several studies indicate a negative health effect of trans fatty acids, consumer demands will urge the food producers to lower the content of trans fatty acids in their products. This article describes the option to reduce the trans levels in the hydrogenation of an edible oil by changing process conditions and by applying alternative low trans heterogeneous catalysts.