The Dimerization of Oleic Acid with a Montmorillonite Catalyst II: GLC Analysis of the Monomer; the Structure of the Dimer; a Reaction Model

In the previous communication it was suggested that during the dimerization of oleic acid with montmorillonite catalyst a hydrogen transfer reaction takes place. This leads to a saturated fatty acid molecule and a dienoic acid molecule, which easily reacts to cyclic dimers and bicyclic trimers. In order to corroborate the hypothesis of this hydrogen transfer reaction, the monomer fraction, obtained after molecular distillation of the reaction product, is investigated mainly by GLC. It is shown that the monomer mixture consists almost exclusively of saturated fatty acids both of straight and branched structure, while no cyclic products are present in it. The intermediate formation of dienoic acids implies that the dimers and trimers are probably cyclic, which could be proved experimentally. On the basis of these results a reaction model is proposed.     

Addition of aromatic compounds to oleic acid catalyzed by heterogeneous acid catalysts

The addition of aromatic compounds to the double bond of oleic acid was studied using solid acid catalysts. For example, in the presence of an acid clay catalyst (bentonite), phenol reacted with oleic acid to yield 96% of an alkylphenol addition product. When toluene was used as the aromatic reactant, however, the yield of alkylbenzene addition product was less than 2%. In this instance, the major reactions observed were elaidinization and migration of the double bond of oleic acid. The addition of phenol to oleic acid in greater than 95% yield also was accomplished with the use of a sulfonic acid ion-exchange resin catalyst. This same catalyst also catalyzed the addition of toluene and benzene to oleic acid to yield 82% and 22%, respectively, of alkylbenzene-type addition products. In the latter instances, the major side product formed was γ-stearolactone. Capillary gas chromatographic (GC) analyses of the alkylbenzene addition products obtained showed them to be mixtures of positional isomers. The isomer distributions were subsequently determined by GC-mass spectrometry (MS). Visiting Scientist, Nippon Oil and Fat Co., Japan.     

Building of a sulfonyl‐group‐functionalized monomer whose polymer is able to catalyze biodiesel formation

A linear polymer containing sulfonyl groups was synthesized from a vinyl monomer to use its acid group as a catalyst of the esterification of oleic acid to form biodiesel. First, synthesis optimization of the monomer was carried out in an aqueous system. This molecule was obtained in an excellent yield, where the pH and reaction time were decisive factors in the synthesis performance. The vinyl monomer was then polymerized, and the catalytic activity of the sulfonic acid could be demonstrated in the esterification of oleic acid with short‐chain alcohols. The increase in the catalyst content resulted in a higher concentration of the carbonyl group activated, and this was followed by faster esterification kinetics. The highest yield (98 mol %) was reached after 20 min when a 10 mol‐% of catalyst was used. A larger size alcohol led to slower esterification kinetics because its ability as a nucleophile was decreased by steric impediment. The sulfonyl group in polymer 4 , an aryl sulfonic acid polymer, proved to be an acid almost as efficient as sulfuric acid, although the former worked in a heterogeneous system. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41957.     

Variables affecting the yield of normal oleic acid produced by the catalytic hydrogenation of cottonseed and peanut oils

Summary 1. The effects of the following factors have been investigated in the hydrogenation of cottonseed and peanut oils: temperature, concentration of catalyst, pressure of the hydrogen, degree of agitation, and nature of the nickel catalyst. 2. The formation of stearic acid was found to be repressed and the formation of “iso-oleic” acid simultaneously favored by increasing the temperature, increasing the catalyst concentration, decreasing the pressure, and decreasing the agitation. 3. The nature of the nickel catalyst, as influenced by its method of preparation, may have a large effect on the composition of the hydrogenated product. One of the nickel catalysts investigated formed excessive amounts of iso-oleic acid without being correspondingly selective. 4. In the hydrogenation of cottonseed oil, within a comparatively wide range of conditions, the production of total solid acids with a given catalyst is relatively constant, since the conditions leading to the formation of stearic and iso-oleic acid are mutually exclusive. Extremes in either direction, however, lead to the production of excessive amounts of total solid acids. 5. Peanut oil is a more suitable raw material than cottonseed oil for the production of normal oleic acid, because of its initially greater content of this constituent and its lesser content of linoleic acid. 6. On the assumption that a quantitative separation could be made of the liquid acids from the solid acid fraction (saturated and iso-oleic) of the hydrogenated products, leaving minor amounts of unhydrogenated linoleic acid as an impurity in the separated normal oleic acid, the following maximum yields of “impure normal oleic acid” could be obtained: from cottonseed oil, 56 per cent of oleic acid of 85 per cent purity, 53 per cent of oleic acid of 90 per cent purity, and 48 per cent of oleic acid of 95 per cent purity; and from peanut oil, 70 per cent of oleic acid of 85 per cent purity, 68 per cent of oleic acid of 90 per cent purity, and 66 per cent of oleic acid of 95 per cent purity. Presented before the American Oil Chemists’ Society, Houston, Texas, April 30 to May 1, 1942.     

Zusammensetzung und Anwendungen von Isostearinsäure

Composition and Application of Isostearic Acid The clay catalysed oligomerisation of unsaturated fatty acids yields C36 dimer fatty acids, C54 trimer fatty acids and C18 monomer fatty acids. Monomer fatty acids, which consists mainly of straight, branched, saturated and unsaturated fatty acids, can be distilled from the higher molecular weight products and after hydrogenation separated into solid stearic acid are mono- and polybranched C18 fatty acids whose branching points are mainly concentrated in the center of the molecule. Depending on the nature of the used raw materials and the degree of refinery, straight chain fatty acids, cyclic fatty acids, γ-lactones, unsaponifiable and even rosin acids are found as impurities. The low cloudpoint, comparable with oleic acid, as well as the excellent temperature- and oxidation stability gives isostearic acid and their derivatives excellent opportunities in applications as cosmetics, lubricants and plastics.     

Adsorption studies of fatty acids on montmorillonite‐based filler clay

Surface coating of montmorillonite‐based filler clay with stearic and oleic (9‐octadecenoic acid) acids was presented. Sedimentation measurements showed that the sedimentation rate and the sediment volume decreased sharply with the adsorbed amount of the acid up to a certain concentration and then became constant. The chemical analysis showed that the adsorbed amount of either acid by montmorillonite clay increased with the equilibrium concentration of the acid in the solution. The adsorption isotherm indicated the formation of a monolayer on the clay surface at a lower concentration of the acids followed by formation of multilayers of the acids on the clay surfaces at higher concentrations. XRD analysis indicated no intercalation of either acid in the lamella of the clay. We concluded the possibility of surface coating of montmorillonite clay with a monolayer of fatty acids that render the clay organophilic. The adsorption of either acid improved the dispersibility of the clay particles in organic or polymeric media. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2574–2580, 2002     

Characterization of products from clay catalyzed polymerization of tall oil fatty acids

Products obtained by acid clay catalyzed dimerization of oleic, elaidic, and tall oil fatty acids were characterized. The monomeric products (35% of total) consisted of stearic, octadecenoic (66%trans-), and mid chain monomethyl branched acids, both saturated and unsaturated. The polymeric products (65% of total) consisted of linear, alicyclic, aromatic, and polycyclic dimers. The tall oil fatty acid based dimer closely resembled oleic dimer in polycyclic character and linoleic dimer in aromatic and linear structures. Oleic dimers contained the highest linear structural content, while linoleic dimer contained the largest polycyclic content. Alicyclic structures were the principal components of all three products. The monocyclic dimer structures present consisted of six membered ring systems with linoleic and tall oil fatty acid dimers containing the highest aromatic contents. Presented at the National American Chemical Society Meeting, New York, August 1972.     

Estolide production with modified clay catalysts and process conditions

The 20% yields of estolides prepared from oleic acid and meadowfoam oil fatty acids are improved when the montmorillonite clay catalysts are modified to increase their activity. Changes we explored included acidifying the clay, treating to increase the surface area of clay to introduce new active sites, and decreasing the ionic character of the clay surface to enhance adsorption of the fatty acids. We also evaluated the use of higher levels of clay in the reactions. Clays treated with Fe³⁺ salts increase the estolide yield from 21 to 27%, a 28% increase. Clay catalysts were also treated with surface-active reagents. The most active were cationic surfactants, and montmorillonite clays treated with cetyltrimethylammonium chloride increased the estolide yield to 30%. Estolide yields could not be improved beyond 30% by increasing the amount of clay. However, nitrogen sparging increases the efficiency of stirring and increased the estolide yield to 35% estolide.     

Preparation of hydroxy acids by sulfation of oleic and linoleic acids

Summary Monohydroxystearic acids were prepared by sulfation and subsequent hydrolysis of oleic acid, and the effect of reaction conditions on yield was studied. Monohydroxystearic acids were obtained from commercial oleic acid in 72% yield and from pure oleic acid in 86% yield. Conditions for the best yields apparently gave increased amounts of isomeric hydroxy acids. Hydroxy acids prepared by the sulfation and subsequent hydrolysis of linoleic acid were converted to methyl esters, and purified by fractional distillation and low temperature crystallization. Experimental evidence indicates that sulfuric acid reacts with one double bond of linoleic acid to form isomeric monohydroxyoleic acids and with both double bonds to form dihydroxystearic acids. The by-products formed by the sulfation of linoleic acid include both ester-type polymers and additional polymeric material which cannot be converted to monomers by alkaline saponification. When commercial oleic acid is sulfated and subsequently hydrolyzed, the monohydroxystearic acid thus obtained presumably contains monohydroxyoleic acids and dihydroxystearic acids resulting from the linoleic acid present in the starting material. The formation of an unsaponifiable polymer during the sulfation of linoleic acid accounts in part for the lower yield of hydroxy acids obtained from commercial oleic acid, as compared with that of purified oleic acid. One of the laboratories of the Bureau of Agricultural and Industrial Ohemistry, Agricultural Research Administration, U. S. Department of Agriculture.     

单体酸混合物成分的GC-MS分析

研究了生产二聚酸时得到的副产品单体酸的化学组成的GC MS分析方法,样品首先用质量浓度为140g/L KOH M eOH进行甲酯化,然后用GC MS进行分析和鉴定,共鉴定出棕榈酸、肉豆蔻酸、10甲基月桂酸、12甲基十四烷酸、十八烯酸等13种物质,总脂肪酸的质量分数占76.71%,其中饱和酸占66.36%,不饱和酸占10.35%,其中直链酸占饱和脂肪酸的41.02%,支链酸即异构酸占饱和脂肪酸的58.98%。     

Esterification reaction of oleic acid with a fusel oil fraction for production of lubricating oil

In this study, the esterification of oleic acid with a fraction of fusel oil was investigated. The variables that affect ester yield, such as temperature, molar ratio of oleic acid to alcohol, and amount of catalyst, were determined. Powdered silica gel was chosen to remove water instead of granular silica gel, magnesium sulfate, or benzene. The behavior of amyl alcohols and the fusel oil fraction was compared. The esterification reaction was carried out under the reaction conditions selected as optimal, and the ester conversion of the reaction was 97.3%. The product mixture compressed products, excess reactants, catalyst, and desiccant. Oleate ester and oleic acid (2.7%) were obtained using the refinement steps of filtration, evaportation, washing with distilled water, and drying over sodium sulfate.     

油溶性表面活性剂甘油硼酸油酸酯的合成研究

以硼酸和油酸为原料采用直接酯化法合成水溶性的甘油硼酸酯,再在催化剂的作用下与油酸反应制得甘油硼酸油酸酷,设计出较佳的酸化条件：甘油硼酸酯与油酸摩尔比1：0．9,温度220℃,时间4h,催化剂甩量（脂肪酸质量分数）0．5％,酸转佬率98．5％。     

Polymerization of dehydrated castor acids using an acid earth catalyst

The atmospheric pressure polymerization of a commercial dehydrated castor oil fatty acid mixture, by using as catalyst the acid clay Filtrol 13, has been studied under different conditions of temperature, catalyst concentration, reaction time, and concentration of conjugated linoleic acid in the starting material. At 180C or above, extremely rapid polymerization of the conjugated fatty acids occurred (50% complete in about 4 min at 66% concentration). This was accompanied bytrans isomerization and some hydrogen transfer to form oleic (oriso-oleic) acids. The ratio of dimer/polymer in the product was approximately 2 to 2.5 and was only slightly affected by variation in the reaction conditions.     

Quantitative analysis of polymerized fatty acids using gel permeation chromatography

The acid clay catalyzed dimerization of tall oil fatty acids and oleic acid yields commercial products which are complex mixtures of monomers, dimers, trimers, and higher polymers of various structures. Analyses for monomer, dimer, and trimer concentrations are important to ensure good quality control and reproducible end use performance. Techniques for direct determination of monomer, dimer, and trimer acids by gel permeation chromatography are presented. The components are separated using Bio Beads SX-2 gel. Heptanoic acid is used as an internal standard. The standard deviations for determination of dimer, trimer, and monomer are 1.0, 0.4, and 0.2% respectively. Calibration was accomplished using dimer and trimer fractions isolated from a preparative scale chromatographic system. It is suggested that a measure of higher polymeric acids can be obtained by difference after correction for neutral materials.     

Synthesis of alkyl‐branched fatty acids

Alkyl‐branched fatty compounds are of interest for industrial products in the cosmetics and lubricant areas. In this review, clay‐ and zeolite‐catalyzed isomerizations of unsaturated fatty compounds, especially of oleic acid, are discussed. While clay‐catalyzed reactions give most complex mixtures of dimeric fatty acids and of monomeric so‐called “isostearic acid”, the zeolite‐catalyzed process yields preferentially an isomeric mixture of isostearic acids having the methyl branch on the 8–14 positions of the alkyl chain. Synthetically useful additions of alkyl radicals can only be performed on ω‐unsaturated fatty compounds, whereas perfluoroalkyl iodides were added to fatty compounds with terminal as well as internal double bonds using electron transfer‐initiated radical addition reactions. Electrophilic additions of alkyl carbenium ions generated by decomposition of alkyl chloroformates by ethylaluminum sesquichloride give well‐defined alkyl‐branched oleochemicals with good yields.     

环氧单丙烯酸酯的合成

采用乙酰丙酮和三氯化铬制备乙酰丙酮铬(Ⅲ)络合物,主要讨论pH值对产物产率的影响。通过连续滴加碱溶液的方式控制体系pH值于7.0左右,可使络合物产率达到70%以上。并以有机铬络合物作为催化剂催化环氧树脂与丙烯酸的酯化反应,研究了催化剂用量及温度等对反应速率的影响,对酯化产物进行了红外光谱表征。结果表明,乙酰丙酮铬(Ⅲ)是一种有效的催化剂,当其用量为环氧树脂和丙烯酸用量的0.1%~0.2%,在110~120℃反应1.5~2.5 h,在较短时间内可达到较高的转化率。经红外光谱测试和计算,环氧基转化率约为48.56%,与理论值基本一致。     

Preparation and evaluation of alpha-cellulose sulfate based new heterogeneous catalyst for production of biodiesel

Alpha-cellulose obtained from wood sawdust wastes in 29.0% yield was reacted with sulfuric acid to produce alpha-cellulose sulfate materials. These catalyst materials were characterized by Fourier transform infrared and specular reflectance-UV spectroscopy, scanning electron microscopy, and laser scattering particle size distribution. The concentration of sulfate groups on the cellulosic matrix was determined by turbidimetry. The obtained alpha-cellulose sulfates can be used as efficient heterogeneous catalysts for biodiesel production from palm oil when evaluated with methylation of palmitic acid and oleic acid as the model reaction. The density of sulfate functional groups on the alpha-cellulose sulfate materials was 2.18–16.74% wt/wt as determined by turbidimetry. Standardization of deployed alpha-cellulose sulfate catalysts was achieved using different ratios of alpha-cellulose and sulfate (1:0.5, 1:1, 1:2, and 1:4 m/v). Additionally, the Bronsted acid sites on the alpha-cellulose sulfate catalyst play a pivotal role in the catalytic process.     

对甲苯磺酸催化制备油酸异丙酯及动力学研究

油酸与异丙醇在对甲苯磺酸催化剂的作用下发生酯化反应制备油酸异丙酯,研究了催化剂用量、醇酸配比、反应时间、反应温度等对转化率的影响。结果表明,催化剂的量4%,醇酸体积比2.5∶1(摩尔比10.3∶1),反应温度75℃,反应时间5 h,酯化率达到91.8%。动力学计算表明,对甲苯磺酸催化制备油酸异丙酯的反应级数为1级,频率因子A=611.1,反应活化能为24.0 kJ/mol。     

Synthesis of Fatty Acid Esters of Selected Higher Polyols Over Homogeneous Metallic Catalysts

Studies on the synthesis of esters of natural origin fatty acids (oleic acid) and a branched synthetic isostearic acid derived from oleic acid with commercially available selected higher polyols in the presence of homogeneous metallic catalysts have been carried out. The effects of the synthesis temperature, molar ratio and the catalysts amount have also been studied. It was shown that higher fatty acid conversion and selectivity to tri‐ and tetraesters were obtained for organotin catalyst Fascat 2003, which was used as the esterification catalyst. Anti‐wear test confirmed good tribological properties of the obtained esters.     

固体酸催化棉籽油酯交换制备生物柴油

生物柴油(脂肪酸甲酯)可以由棉籽油与甲醇在酸催化剂的作用下通过酯交换反应制得. 通过硫酸改性氧化钛、氧化锆,并经过高温煅烧得到了相应的固体强酸催化剂TiO2-SO42-, ZrO2-SO42-,并对催化剂活性进行了评价. 实验结果表明,TiO2-SO42-和ZrO2-SO42-与改性前的氧化物相比具有较高的酯交换反应活性. 在230℃、醇油摩尔比12:1及催化剂用量为棉籽油2%(w)的条件下,反应8 h后甲酯的收率达到90%以上. 与固体碱催化剂相比,固体酸催化剂对原料的酸度有更强的适应性. 红外吡啶吸附光谱表明,TiO2-SO42-与ZrO2-SO42-具有较强的L酸和B酸中心.