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1.
J. A. Monick 《Journal of the American Oil Chemists' Society》1979,56(11):853A-860A
“Fatty” or higher alcohols are mostly C11 to C20 monohydric compounds. In probably no other homologous aliphatic series is the current balance between natural and synthetic
products so vividly evident. Natural sources, such as plant or animal esters (waxes), can be made to yield straight chain
(normal) alcohols with a terminal (primary) hydroxyl, along with varying degrees of unsaturation. In the past, socalled fatty
alcohols were prepared commercially by three general processes from fatty acids or methyl esters, occasionally triglycerides.
Fatty acids add hydrogen in the carboxyl group to form fatty alcohols when treated with hydrogen under high pressure and suitable
metal catalysts. By a similar reaction, fatty alcohols are prepared by the hydrogenation of glycerides or methyl esters. Fatty
alcohols are also prepared by the sodium reduction of esters of fatty acids in a lower molecular weight alcohol. The sodium
reduction method was ordinarily too expensive; it was displaced early by the other methods; finally most unsaturated alcohols
made by this route were largely replaced. Methyl ester reduction continues to provide perhaps 20% of the saturated fatty alcohols,
and selective hydrogenation with the use of special catalysts such as copper or cadmium oxides was developed for the production
of oleyl alcohol. Synthetic or petroleum technology for long chain alcohols include the Ziegler process, useful for straight
chain, even-numbered saturated products. A second is the carbonylation and reduction of olefins affording medium or highly
branched chain alcohols. Paraffin oxidation affords mixed primary alcohols. Fatty alcohols undergo the usual reactions of
alcohols. They may be reacted with ethylene oxide to yield a series of polymeric polyoxyethylene alcohols or with acetylene
under pressure to yield vinyl ethers or with vinyl acetate to give vinyl ethers. 相似文献
2.
Selective hydrogenation of fatty acids and methyl esters of fatty acids to obtain fatty alcohols–a review
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María A Sánchez Gerardo C Torres Vanina A Mazzieri Carlos L Pieck 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2017,92(1):27-42
In this paper, a review is presented of the evolution of different catalytic systems and operating conditions used in the selective hydrogenation of acids and esters of fatty acids to obtain fatty alcohols, which have broad industrial applications in the oleochemical industry. In addition, the current status of the different technologies used industrially (Lurgi, Davy and Henkel) for obtaining fatty alcohols, as well as major global sources of raw materials for the oleochemical industry are put forward. Finally, the reaction mechanisms of the selective hydrogenation process of oleic acid and methyl oleate to obtain the corresponding unsaturated alcohol as well as the new catalysts proposed by researchers are described. © 2016 Society of Chemical Industry 相似文献
3.
Copper oleate and cadmium oleate catalysts have been replaced by other metal compounds. Silver was the only metal which could
be substituted for copper in the ratio range studied. Using nickel oleate, the degree of saturation of the double bond decreased
with increasing cadmium oleate concentration. No comparable substitute was found for Cd. The composition of the final components
is influenced by the use of a paraffinic solvent, which also has an effect on the saturation of the double bond. An explanation
is given for the behavior of the catalyst when the reaction is not selective and is carried out in a paraffinic solvent. The
catalytic system Ag/Cd soaps was also studied kinetically and analytically. The results show that the mechanism of the reaction
using silver soap is identical with the one using copper soap. 相似文献
4.
Aeromonas hydrophila N‐6, isolated from a soil sample, converted vegetable oils to several rare unsaturated fatty acids and alcohols accumulated inside the cells as a wax ester form. A. hydrophila N‐6 effectively decreased fatty acid chain lengths, and converted rapeseed, safflower and linseed oils into 7‐16:1 and 5‐14:1 fatty acids, 7,10‐16:2 and 5,8‐14:2 fatty acids, and 7,10,13‐16:3 fatty acids, respectively. Furthermore, A. hydrophila N‐6 reduced the resulting fatty acids to rare unsaturated fatty alcohols, such as 7‐16:1, 5‐14:1, 9,12‐18:2, 7,10‐16:2, 9,12,15‐18:3 and 7,10,13‐16:3. Such unsaturated fatty acids and alcohols are rarely found in natural oils. Because decreasing fatty acid carbon chain lengths from the carboxyl end and reducing unsaturated fatty acids to unsaturated fatty alcohols in industrially applicable scale are both difficult reactions to accomplish by chemical means, we suggest that A. hydrophila N‐6 may facilitate the introduction of new bioprocesses for producing rare unsaturated fatty acids and alcohols, especially fatty alcohols with more than two double bonds. 相似文献
5.
6.
A. Gangadhar R. Subbarao G. Lakshminarayana 《Journal of the American Oil Chemists' Society》1984,61(7):1239-1241
Hydroxylamine has been recently found to react with ethyl acetate to generate diimide in situ. This reaction was used to reduce
10-undecenoic, oleic, linoleic, stearolic, concentrates of ricinoleic, cyclopentene and cyclopropene fatty acids (FA), dehydrated
castor oil FA, 10-undecen-1-ol, oleyl alcohol and castor fatty alcohols. Unsaturated FA and their corresponding alcohols reacted
in a similar manner. Terminally unsaturated, cyclopropene and cyclopentene FA were more reactive than oleic acid, which, in
turn, was more reactive than hydroxymonoenoic acids. Conjugated dienoic FA reduced faster than nonconjugated dienoic acids.
Partial hydrogenation using this reagent is particularly advantageous in determining geometry and the position of double bonds
in the polyunsaturated FA, as it can be carried out in the absence of oxygen or oxidizing agents unlike hydrazine reductions. 相似文献
7.
Frank Th. van de Scheur Guido U-A Sai Alfred Bliek Leendert H. Staal 《Journal of the American Oil Chemists' Society》1995,72(9):1027-1031
In the synthesis of fatty alcohols by hydrogenolysis of fatty acid methyl esters, small amounts of free fatty acids in the
feed negatively affect the reactivity of copper-silica based catalysts. The effect of the acid was investigated in relation
to the production of water, the nature of the inhibiting species, and the degree of reduction of the catalyst. Inhibition
is reversible and not due to catalyst deactivation. Water is not the inhibiting species. Furthermore, formation of copper
and zinc soaps was excluded. Lauric acid in the methyl ester feed reacts preferentially, but at a lower rate than the ester.
Inhibition most likely stems from a preferential adsorption of the acid at the active sites of the catalyst. The consequences
for practical applications are discussed. 相似文献
8.
Helmut Klimmek 《Journal of the American Oil Chemists' Society》1984,61(2):200-204
The effect of various impurities which reduce the activity of nickel catalysts during fatty acid hydrogenation has been studied.
It is here proposed to divide the compounds which negatively influence the nickel-based fatty acid hydrogenation process into
three categories, namely, catalyst poisons, inhibitors and deactivators, each group acting according to a different mechanis.
The deleterious effect of typical catalyst poisons, such as S, N, P or Cl, is more or less independent of the chemical nature
of the individual organic compounds containing these elements. There is good correlation between these element contents and
the required nickel catalyst loading level. Other typical impurities present in technical fatty acids, such as oxidized fatty
acids, soaps and water, also diminish the catalyst activity considerably. A number of experiments were designed to study the
influence of various pretreatments of fatty acids on the catalyst loading levels needed for hydrogenation. In view of the
high cost of nickel catalysts, considerable savings can be obtained by pretreatment of fatty acids prior to hydrogenation.
Such pretreatment steps may include sulfuric acid washing, application of spent catalysts, and/or distillation. The most economical
method will depend on local circumstances. 相似文献
9.
Federica Zaccheria Nicoletta Ravasio Carine E. Chan-Thaw Nicola Scotti Paolo Bondioli 《Topics in Catalysis》2012,55(7-10):631-636
An efficient copper catalyst for the one-pot one-step hydrogenation?+?esterification of unsaturated free fatty acids is described. The high selectivity in hydrogenation promoted by copper, combined with the high activity in esterification observed with solid mixed oxides allows one to directly obtain stabilized methyl esters. 相似文献
10.
Fatty methyl ester hydrogenation to fatty alcohol part I: Correlation between catalyst properties and activity/selectivity 总被引:1,自引:3,他引:1
Ross D. Rieke Deepak S. Thakur Brian D. Roberts Geoffrey T. White 《Journal of the American Oil Chemists' Society》1997,74(4):333-339
Fatty alcohols, derived from natural sources, are commercially produced by hydrogenation of fatty acids or methyl esters in
slurry-phase or fixed-bed reactors. One slurry-phase hydrogenation of methyl ester process flows methyl esters and powdered
copper chromite catalyst into tubular reactors under high hydrogen pressure and elevated temperature. In the present investigation,
slurry-phase hydrogenations of C12 methyl ester were carried out in semi-batch reactions at nonoptimal conditions (i.e., low hydrogen pressure and elevated
temperature). These conditions were used to accentuate the host of side reactions that occur during the hydrogenation. Some
14 side reaction routes are outlined. As an extension of this study, copper chromite catalyst was produced under a number
of varying calcination temperatures. Differences in catalytic activity and selectivity were determined by closely following
side reaction products. Both activity and selectivity correlate well with the crystallinity of the copper chromite surface;
they increase with decreasing crystallinity. The ability to follow the wide variety of side reactions may well provide an
additional tool for the optimized design of hydrogenation catalysts. 相似文献
11.
E. H. Pryde 《Journal of the American Oil Chemists' Society》1984,61(2):419-425
When hydroformylation of unsaturated fatty materials is done with rhodium-triphenyl phosphine (or phosphite) catalysts, a
number of advantages become apparent compared to cobalt carbonyl-catalyzed reactions. With rhodium, the reaction can be carried
out (a) at pressures as low as 200 psi, (b) at each double bond location in a polyunsaturated fatty acid, and (c) in high
yield and conversion. Solubilized catalyst can be recovered from distillation residue and readsorbed on spent catalyst support
by thermal treatment in a rotary kiln. The reconstituted catalyst is more active than the original catalyst and can be recycled
indefinitely at a relatively low cost. Recently developed supports for “homogeneous” catalysis may make catalyst recovery
even more effective. Acetalation, oxidation with air to polycarboxylic acids and catalytic hydrogenation to hydroxymethyl
compounds can be done easily and in high yield on mono-, di- and triformyl derivatives alike. Other reactions investigated
for monoformyl fatty esters include reductive amination to form aminomethyl derivatives and Tollen’s condensation with formaldehyde
to form geminal,bis-hydroxymethyl compounds. although the Northern Center has carried out some basic investigations on the hydroformylation reaction
and on the chemistry of the hydroformylated products, there is a great deal more that can be done with regard to synthesis
of new compounds and development of new applications. 相似文献
12.
Manufacture of fatty alcohols based on natural fats and oils 总被引:1,自引:0,他引:1
Udo R. Kreutzer 《Journal of the American Oil Chemists' Society》1984,61(2):343-348
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. 相似文献
13.
Frits van der Klis Marinus H. van den Hoorn Rolf Blaauw Jacco van Haveren Daan S. van Es 《European Journal of Lipid Science and Technology》2011,113(5):562-571
Long‐chain internal olefins were prepared by silver(II)‐catalyzed oxidative decarboxylation of unsaturated fatty acids by sodium peroxydisulfate. Similar to saturated carboxylic acids, 1‐alkenes were the major decarboxylation product in the additional presence of copper(II), whereas in the absence of copper(II) alkanes were predominantly formed. In both cases, the internal unsaturation of the fatty acids remained largely intact, although the moderate yields indicated that side reactions occurred to a significant extent. The simple procedure makes this multistep one‐pot reaction useful for the synthesis of a variety of internally unsaturated hydrocarbons. The purified products, almost all of which are prepared for the first time, may serve as reference compounds for studies on the heterogeneously catalyzed decarboxylation of triglycerides and fatty acids in the absence of hydrogen. Practical applications: The products of the chemistry described in this contribution, i.e., unsaturated long‐chain hydrocarbons, provide bio‐based building blocks for further chemical modification toward products which may be applied as (bio)fuels, lubricants, solvents, and polymeric materials. 相似文献
14.
W. Zschau 《European Journal of Lipid Science and Technology》1979,81(8):303-310
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. 相似文献
15.
The hydrogenation of trans,4-phenyl,3-buten,2-one (benzalacetone) and trans,3-phenyl, propenal (cinnamaldehyde) was carried out on Au supported on iron oxides catalysts. Commercial goethite (FeOOH), maghemite (γFe2O3) and hematite (αFe2O3) were used as supports. The catalytic activity of Au/Fe2O3 reference catalyst, supplied by the World Gold Council, was also investigated. Gold catalysts and the parent supports were characterized by BET, X-ray diffraction (XRD), temperature programmed reduction (TPR), temperature programmed desorption of ammonia (NH3-TPD) and high resolution transmission electron microscopy (HRTEM).Among the catalysts investigated Au supported on FeOOH shows the highest activity and selectivity to UA in the hydrogenation of unsaturated carbonyl compounds whereas Au supported on αFe2O3 are the less active and selective catalysts.The catalytic activity and selectivity to unsaturated alcohols (UA) in the hydrogenation of benzalacetone and cinnamaldehyde are less influenced by the morphology of gold particles and are mainly influenced by the nature of the support.A correlation between the reducibility of the catalysts and the activity and selectivity to UA has been found. Increasing the reducibility of the catalysts both the activity and selectivity to UA increase. These results let us to argue that active and selective sites are formed by negative gold particles formed through the electron transfer from the reduced support to the metal. 相似文献
16.
17.
Production of fatty alcohols from fatty acids 总被引:3,自引:0,他引:3
Detergent-range alcohols from natural feedstock can be produced by high pressure hydrogenation of either methyl esters or
fatty acids. The increasing quantities of fats and oils on the world market secure a reliable and economically priced material.
Although fatty acid is an abundant worldwide commodity, most alcohol producers hydrogenate methyl esters, because direct hydrogenation
of fatty acids is difficult as the catalyst is sensitive to acid attack. The process described here makes it possible to hydrogenate
fatty acids directly to alcohols of high quality without prior esterification. The reaction takes place in the liquid phase
over a fine-grained copper chromite slurry in a single reactor vessel. A special reactor design with an optimum arragement
of the feeding nozzles causing an appropriate circulation of the reacting components inside the reactor facilitates the rapid
“in situ” esterification reaction. This minimizes the free fatty acid concentration in the reactor to nearly zero. This results
in a low consumption of catalyst. The most important advantages of the process are: direct feed of fatty acids of various
origins, use of reasonably priced raw materials such as soapstock fatty acids and lower grade tallow acids, no process steps
with methanol, and excellent economics. The process is industrially proven. 相似文献
18.
The kinetics and mechanism of the Cu and Cd-soap-catalyzed hydrogenation of oleic acid have been studied. The reaction is
first order in Cd and H2, and also first order in Cu if the double bond is completely preserved during reduction of the carboxyl group to the hydroxyl
group. It will deviate from this order if the selectivity is lower owing to an increased Cu concentration. The reaction rate-determining
step is independent of the Cd concentration. Its activation energy, of 13.4 kcal/mole, corresponds to that of the chemisorption
of hydrogen on Cu. Unsaturated and saturated fatty acids of the same chain length have the same reaction rate. A decrease
of the chain length causes a decrease in the reaction rate and in the final degree of conversion. Water and low molecular
weight acids have an inhibitory effect on the reaction. A reaction mechanism is proposed which is based on the assumption
that cadmium oleate plays a double role: it stabilizes the copper sol and is intermediate for the hydrogenation. 相似文献
19.
Richard R. Egan Gary W. Earl Jeannene Ackerman 《Journal of the American Oil Chemists' Society》1984,61(2):324-329
A number of unsaturated fatty alcohols are known, but only those of the C16 and C18 chain lengths are of much importance. In particular, oleyl alcohol., 9,10-octadecenol-1, is by far the most important. A
variety of grades of oleyl alcohols is produced and used in the USA ranging from high purity material having iodine values
(IV) of 90–95 to those having IV of 45–55, with the other components being primarily cetyl (hexadecanol-1) and stearyl (octadecanol-1)
alcohols. This paper takes a brief look at the various grades of unsaturated alcohols used in the USA, methods of preparation,
and the change in physical and chemical properties as the octadecanol-1 content and IV decline. Uses of these alcohols industrially
and in cosmetic and pharmaceutical preparations are also discussed. Unsaturated alcohols are useful chemical intermediates
since they have two reactive sites, the hydroxyl group and the carbon-carbon double bond. Particular attention is paid to
the properties, uses and potential uses of some of their sulfates, ether sulfates, ethylene oxide adducts and ethylene/propylene
oxide adducts as detergents and emulsifiers for ultimate use in cosmetics and light-duty and heavy-duty systems. Current estimated
consumption of unsaturated alcohols in the USA is discussed. 相似文献
20.
R. O. Feuge E. A. Kraemer A. E. Bailey 《Journal of the American Oil Chemists' Society》1945,22(8):202-207
Summary 1. An investigation has been made of the esterification of glycerol and peanut oil fatty acids under reduced pressure, with
and without the assistance of various metal chlorides and oxides as catalysts.
2. The uncatalyzed reaction is bimolecular in character but proceeds in two successive stages, of which the latter has the
lower velocity constant. Velocity constants have been determined for the initial and final stages of the reaction, at intervals
between 166° and 241° C. The calculated heats of activation for the initial and final stages of the reaction are respectively
12,300 and 10,800 calories per mole. The free fatty acid concentration corresponding to the termination of the first stage
decreases progressively as the temperature of the reaction is increased.
3. Of a wide variety of metal oxides and chlorides tested, zinc and tin chlorides were outstanding in catalytic activity.
The reaction, when catalyzed with these materials, is complex and no longer simply bimolecular. It is believed that tin and
zinc chlorides react initially with free fatty acids and free glycerol to form metal soaps and chlorohydrins, and that esterification
proceeds through interaction of these two initial reaction products. Other metal chlorides, including the chlorides of aluminum,
antimony, mercury, nickel, magnesium, manganese, lead, iron, and cadmium, do not appear to be capable of reacting in this
manner, and are relatively poor catalysts. The oxides of tin and zinc are also deficient in catalytic activity, as is hydrochloric
acid.
4. The reaction proceeds at a reasonable speed, i.e., the FFA content of the product is reduced to about 3% in 6 hours, if
0.0008 mole of tin chloride per 100 g. of fatty acids is used as a catalyst at 175° C. or if a similar amount of zinc chloride
is used as a catalyst at 200° C. Equally rapid esterification is obtained without a catalyst only above 250° C. Esterification
is assisted by maintaining a vacuum upon the reaction vessel to remove water vapor from the reacting material as rapidly as
it is formed. A vacuum of about 20 mm. pressure of mercury is satisfactory.
5. If zinc or tin chloride catalysts are employed, the metals may be completely removed from the esterified oils by ordinary
alkali refining. These catalysts do not cause the oil to polymerize during the course of esterification, do not cause conjugation
in the oils, and are not detrimental to the color of the product.
One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S.
Department of Agriculture. 相似文献