Extreme—Pressure lubricant tests on jojoba and sperm whale oils

Laboratory and simulated in-use lubricant tests were performed on sulfurized jojoba oil and on reference sulfurized sperm whale oil. Data from these comprehensive tests indicated sulfurized jojoba oil prepared from heat-treated filtered oil to be comparable or superior to sulfurized sperm whale oil as an extreme-pressure additive for motor oils, gear lubricants, and automotive transmission fluids.     

Structural determination and uses of jojoba oil

The predominating molecular species in jojoba oil iscis-13-docosenylcis-11-eicosenoate (erucyl jojobenoate), ranging from 31% to 45% of the extracted seed oil. Other alcohol/acid combinations contribute to the C₄₂ molecular chain length so that this fraction constitutes a low of 41% to a high of 57% of the total wax esters. The positions of the exclusivelycis ethylenic bonds in the alcohol and acid moieties of the wax esters are 99% ω-9 and 1% ω-7. Only 2% of the alcohol and acid moieties were saturated when analyzed after saponification of the oil. Triglycerides were detected by gas chromatography in all of the more than 200 natural jojoba oil samples tested, a few of which had substantially more than the normal 1%. Among the many uses of jojoba oil cited here, the two most promising are the sulfurized oil as extreme-pressure/extreme-temperature lubricant additive and the natural or refined oil formulated into cosmetic products.     

Saturated and Unsaturated Wax Esters Produced by Acinetobacter sp. HO1-N Grown on C16-C20 n-Alkanes

The wax ester compositions produced by the action of Acinetobacter sp. HO1-N on n-alkanes (C₁₆ through C₂₀) were analyzed using capillary gas chromatography/mass spectrometry (GC/MS). The wax esters contained, surprisingly, a large percentage of mono-and diunsaturated components. The acyl and alkoxy segments are reported for each wax ester component. Also, the positions of the carbon-carbon double bonds in the wax esters produced from the C₁₆ and C₂₀ n-alkanes are reported. These microbial-produced wax ester mixtures bear a close chemical similarity to those of sperm whale and jojoba oils.     

Sulfurized vegetable oil products as lubricant additives

Sulfurized products based on hog fat and its derivatives have extensive commercial use as additives for metalworking and industrial oils, but only relatively small quantities of vegetable oils find such application in North America. Products were made by sulfurization of soybean, sunflower, cottonseed, high erucic rapeseed, canola,Limnanthes (meadowfoam) and prime lard oils. Unlike products from the wax ester jojoba oil, the sulfurized vegetable triglycerides alone had physical properties generally undesirable for lubricant additives. When the oils were sulfurized in the presence of methyl lardate, however, the products had potential practical application. High-sulfur (active) products were made using a 50:50 ratio of triglyceride to methyl lardate, and low-sulfur (inactive) products were made using a 70:30 ratio. Compared to the other sulfurized vegetable triglyceride products,Limnanthes products showed the best solubility in high viscosity-index paraffinic oil. For solutions, measurements of extreme pressure, friction and wear were compared. Whereas products from jojoba were best, of the triglyceride group theLimnanthes-containing products generally gave the best performance. Although this oil had much promise, it is only in its early stage of commercial development. The other vegetable oils also have potential depending on cost and applications. However, overall competition with the well-established, usually lower-cost products from hog fat or greases would appear to be difficult.     

Wax analysis of vegetable oils using liquid chromatography on a double-adsorbent layer of silica gel and silver nitrate-impregnated silica gel

A chromatographic method is described to measure the crystallizable wax content of crude and refined sunflower oil. It can also be applied to any other vegetable oil. The preparative liquid chromatography step on a glass column containing a silica gel adsorbent superimposed upon a silver nitrate-impregnated silica gel support is used to isolate a wax fraction which is then analyzed by gas chromatography. The recovered wax fraction contains, in addition to the crystallizable waxes, hydrocarbons and other compounds with gas chromatographic retention times corresponding to waxes with chain lengths C₃₄−C₄₂. These compounds are short-chain saturated waxes in fruit oils, such as grapeseed and pomace. In seed oils such as sunflower, soybean or peanut, the compounds initially referred to as “soluble esters” are identified as monounsaturated waxes, esters of long-chain saturated fatty acids, and a monounsaturated alcohol, mainly eicosenoic alcohol. Such waxes are absent from corn or rice bran oils.     

Wax composition of sunflower seed oils

Waxes are natural components of sunflower oils, consisting mainly of esters of FA with fatty alcohols, that are partially removed in the winterization process during oil refining. The wax composition of sunflower seed as well as the influence of processing on the oil wax concentration was studied using capillary GLC. Sunflower oils obtained by solvent extraction from whole seed, dehulled seed, and seed hulls were analyzed and compared with commercial crude and refined oils. The main components of crude sunflower oil waxes were esters having carbon atom numbers between 36 and 48, with a high concentration in the C₄₀−C₄₂ fraction. Extracted oils showed higher concentrations of waxes than those obtained by pressing, especially in the higher M.W. fraction, but the wax content was not affected significantly by water degumming. The hull contribution to the sunflower oil wax content was higher than 40 wt%, resulting in 75 wt % in the crystallized fraction. The oil wax content could be reduced appreciably by hexane washing or partial dehulling of the seed. Waxes in dewaxed and refined sunflower oils were mainly constituted by esters containing fewer than 42 carbon atoms, indicating that these were mostly soluble and remained in the oil after processing.     

Jojoba oil wax esters and derived fatty acids and alcohols: Gas chromatographic analyses

HCl-catalyzed ethanolysis followed by saponification readily surmounts the resistance of long chain wax esters to direct hydrolysis by alkali. Additionally, choosing ethyl instead of methyl esters allows baseline separations between long-chain alcohols and corresponding esters in gas liquid chromatographic (GLC) analysis of total alcohol and acid components before saponification. Liquid wax esters were analyzed on a temperature-programmed 3% OV-1 silicone column. Geographical and genetic effects on the variability of jojoba oil composition were investigated with five different seed samples. Major constituents in jojoba seed oil from shrubs in the Arizona deserts, as indicated by GLC analyses of oil, ethanolysis product, isolated fatty alcohols and methyl esters of isolated fatty acids, were C₄₀ wax ester 30%, C₄₂ wax ester 50% and C₄₄ wax ester 10%; octadecenoic acid 6%; eicosenoic acid 35%, docosenoic acid 7%, eicosenol 22%, docosenol 21% and tetracosenol 4%. Oil from smaller leaved prostrate plants growing along California’s oceanside showed a slight tendency toward higher molecular size than oils from the California desert and Arizona specimens. The wax esters are made up of a dispro-portionately large amount of docosenyl eicosenoate and are not a random combination of constituent acids and alcohols.Lunaria annua synthetic wax ester oil was used as a model for evaluating the analytical procedures. Presented at the AOCS Meeting, Chicago, September 1970 No. Utiliz, Res. Dev. Div., ARS, USDA.     

Sperm oil replacements: Synthetic wax esters from selectively hydrogenated soybean and linseed oils

Synthetic wax esters with properties similar to those of sperm whale oil have been prepared entirely from soybean and linseed oils. the synthesis required: (a) selective hydrogenation of the oils with copper-on-silica gel catalyst, (b) hydrogenolysis of fatty acids to fatty alcohols with copper-cadmiumchromium catalyst, and (c) esterification of hydrogenolysis products to yield predominantly long chain fatty esters which contained unsaturation in both the alcohol and acid moieties. Similarity of physical and chemical properties indicate that these wax esters are possible replacements for sperm oil. After sulfurization, the wax esters also have potential as extreme pressure lubricant additives.     

Fatty acids,fatty alcohols,and wax esters fromLimnanthes douglassi (Meadowfoam) seed oil

Limanathes douglasii seed oil glycerides contain fatty acids which predominantly (97%) have 20 or more carbon atoms. Fatty acids were prepared by saponification; fatty alcohols, by sodium reduction of the glycerides; and liquid wax esters, byp-toluenesulfonic acid-catalyzed reaction of the fatty acids with the fatty alcohols. Solid waxes were prepared by hydrogenation of the glyceride oil and of the wax esters. Chemical and physical constants were determined forLimnanthes douglasii seed oil and its derivatives. The liquid wax esters had properties very similar to those of jojoba (Simmondsia chinensis) seed oil. The solid hydrogenated wax ester was identical in physical appearance and melting point to hydrogenated jojoba seed oil. A laboratory of the Northern Utilization Research and Development Division, Agricultural Research Service, USDA.     

Extraction and Clarification of Orange Wax Obtained from Waste of the Citrus Industry

The processing of the orange leads to a large generation of waste, which is underutilized or discarded. Thus, this study proposes a route to treat oily waste from the orange juice industry, transforming it into a by-product of higher added value to the chemical industry. The orange wax is obtained by hydrodistillation and solvent extraction, and the clarification of the wax is carried out with the oxidative treatment using H₂O₂. A 3² Experimental Design confirmed that the factors, temperature, and concentration of the reactant, influence both response variables, the colorimetric changes and yield. The obtained waxes are characterized by chromatographic (CG-MS), thermal, and rheological analysis. The results of the CG-MS indicate that the clarification method is effective as the components responsible for the pigmentation and odor of the wax cannot be identified after the clarification process. Thermogravimetry analysis and differential exploratory calorimetryindicate a slight increase in thermal stability and a decrease in crystallinity after the clarification process. Rheological analyses show that the obtained waxes present similar flow behavior as commercial beeswax. Therefore, it can be affirmed that this work obtains a green wax from a residue for potential replacement of commercial waxes according to its properties analyzed. Practical applications: This work shows the extraction of orange wax from oily industrial wastes for possible applications in the food and cosmetics industries. The orange wax can be a sustainable substitute for nonrenewable products and supply the wax market due to the high demand. In addition, methods for processing and characterization of the waxes are presented in this work.     

Isomers of monoethylenic fatty acids in some partially hydrogenated marine oils

An analytical study of the monoethylenic isomers in commercial samples of partially hydrogenated herring, whale and seal oils is presented. The results show that with hydrogenated herring oil there is a slight decline in monoenetrans content from 37% in C₁₆ through to 32% in C₂₂. With both whale and seal oils, monoenetrans contents were constant at 54% and 59%, respectively, throughout all chain lengths. In general thecis andtrans positional isomers from hydrogenated whale and seal oils were more scattered than those from hydrogenated herring oil; however in each oil the majorcis isomers of each chainlength were indicative of originalcis fatty acid isomers in the raw oils.     

Fatty acids,fatty alcohols,wax esters,and methyl esters fromCrambe abyssinica andLunaria annua seed oils

Crambe abyssinica andLunaria annua, members of the Cruciferae family, have seed oil glycerides containing ca. 55–65% of C₂₂ and C₂₄ unsaturated fatty acids. Fatty acids were prepared by saponification; fatty alcohols, by sodium reduction of glycerides; liquid wax esters, byp-toluenesulfonic acid-catalyzed reaction of fatty acids with fatty alcohols; and methyl esters, by reaction of fatty acids with diazomethane. Solid hydrogenated glyceride oils and wax esters were compared with several commercial waxes. Chemical and physical constants were determined for the seed oils and their derivatives. Position of unsaturation in theCrambe fatty acids was determined by gas chromatographic analysis of the permanganate-periodate degradation products. The major dicarboxylic acid was brassylic (C₁₃), proving the docosenoic acid to be erucic. Presented in part at the AOCS meeting in New Orleans, La., 1962. A laboratory of the No. Utiliz. Res. & Dev. Div., ARS, U.S.D.A.     

Wax Ester Variation in Olive Oils Produced in Calabria (Southern Italy) During Olive Ripening

The wax ester composition of pressed olive oil and its variation during olive ripening were investigated by column chromatography/GC-on column technique. Six compounds were identified: C₃₆, C₃₈, C₄₀, C₄₂, C₄₄ and C₄₆ wax esters, which were grouped as total detected wax esters (TDWEs). The European Union (EU) includes C₄₀, C₄₂, C₄₄ and C₄₆ waxes (TEWEs) as a distinctive characteristic between different categories, with a maximum total content ≤250 mg/kg for an extra virgin olive oil. The International Olive Council (IOC) includes C₄₂, C₄₄ and C₄₆ waxes (TIOCWEs) as a purity parameter, with a maximum total content ≤150 mg/kg for an extra virgin olive oil. The analytical technique proposed by EU and IOC do not separate the wax esters from fatty acids esters with diterpenic alcohols (phytol and geranylgeraniol) that interfere with detected peaks. Although the examined cultivars were grown in the same geographical area and the same agricultural practices were applied to the trees, ANOVA analysis found significant differences among the oils extracted with the same machinery. The oil produced from the Itrana cultivar showed the lowest content in TEWEs (25.00–39.00 mg/kg) and in TIOCWEs (5.67–9.00 mg/kg). Wax content in Leccino and Pendolino cultivars showed a significant tendency to decrease during olive maturation, and a tendency to increase in all other cultivars from the first to the last harvest date when olive pigmentation changed from green to black.     

Long-chain unsaturated alcohols from jojoba oil by sodium reduction

Summary Jojoba oil is a liquid wax composed essentially of C₂₀ and C₂₂ straight-chain monoethylenic acids and alcohols in the form of esters. Sodium reduction of the wax fatty esters in jojoba oil yielded quantitatively a mixture of unsaturated, long-chain alcohols from the acid moiety of the jojoba oil. Yields of about 91% were obtained in the laboratory-scale experiments and 82 to 86 for the pilot-plant experiments. Analytical data, including detailed infrared spectra information, are given for the resulting product alcohols. Presented at the fall meeting, American Oil Chemists' Society, Cincinnati, O., September 29-October 2, 1957. One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.     

The monounsaturated acyl- and alkyl-moieties of wax esters and their distribution in commercial orange roughy (Hoplostethus atlanticus) oil

Wax esters were isolated from commercial orange roughy (Hoplostethus atlanticus) oil by column chromatography and fractionated by argentation thin layer chromatography. Following transesterification, the resultant fatty acid methyl esters and fatty alcohols were analyzed by gas chromatography. both acyl- and alkyl-moieties were mainly of the monoene structure within the 16∶1–22∶1 range. After derivatization, the positions of the double bonds of even numbered fatty acid and fatty alcohol isomers were located by chromatography-mass spectrometry and compared. Results of these positional analyses indicate that the primary desaturation reactions takes place in the Δ9 position of pre-existing (C₁₄ to C₂₄) acyl chains. It is proposed that acyl components from 18∶1 are subjected to chain elongation to form a mixture of 24∶1 isomers as the final product. Apart from the 24∶1 acyl moiety of the wax esters, in which the double bond was almost exclusively in the Δ15 position, de novo biosynthetic reactions on acids and alcohols appear to yield related acyl- and alkyl-moieties of resynthesized wax esters.     

Composition of insect waxes. I. Waxes of exotic coccidae:Gascardia madagascariensis,Coccus ceriferus andTachardia lacca

Composition of several coccid waxes has been determined by means of alumina and gas-liquid chromatography.Coccus ceriferus wax is a mixture of the esters of C₂₆ and C₂₈ alcohols with C₂₄, C₂₆ and C₂₈ acids.Tachardia lacca wax has a high percentage of free alcohols (essentially C₂₈ alcohol);Gascardia madagascariensis wax contains a large proportion of free acids. In addition to C₂₆, C₃₂ and C₃₄ normal chain acids, there are several C₃₀, C₃₂ and C₃₄ hydroxy acids, in which the hydroxyl function is situated in the middle of the hydrocarbon chain. Small proportions of odd and even hydrocarbons are present in all of the waxes investigated.     

Enrichment of eicosenoic and docosadienoic acids fromLimnanthes oil

The long chain (>C₁₈) monoene and diene acids ofLimnanthes oil are useful in synthesizing diene and tetraene wax ester intermediates for prospective lubricant additives and PVC plasticizers. Low-temperature crystallization of theL. alba acids (61% eicosenoic, 19% docosadienoic, and 20% others) in acetone (initial concentration=0.05 g/ml) at −50 C enriches eicosenoic acid (74%) in the precipitated fraction while concentrating docosadienoic (70%) in the supernatant fraction. This simple and efficient process is well suited for large-scale laboratory separations.     

A comparison of six solvents for the extraction of jojoba seed

Summary Data are presented which show the effects of different solvents on the yield and properties of liquid wax fromSimondsia chinensis (jojoba) and on the characteristics of the hydrogenated waxes obtained from the liquid waxes. Three reagent grade solvents, carbon tetrachloride, benzene, and isopropyl alcohol, and three commercial grade solvents, heptane, hexane, and tetrachloroethylene, were evaluated as extractants for the liquid wax from jojoba. Soxhlet-type of extractions were carried out under conditions in which the solvent was the only significant variable. Four of the solvents extracted essentially the same amount of material from the seed while isopropyl alcohol extracted significantly more material and tetrachloroethylene significantly less. Obviously the difficulties involved in separating the solids recovered from the isopropyl alcohol extraction preclude its use as the extracting solvent for jojoba wax. The density of the liquid waxes varies from 0.8631 to 0.8648; the waxes from the tetrachloroethylene and hexane extractions had the lowest value and the wax from isopropyl alcohol the highest. In each case, regardless of the solvent used, a precipitate developed in the liquid wax after it had been desolventized and stored for 7–10 days. Hydrogenation of clear fractions and precipitate containing fractions of these liquid waxes showed that the precipitate had no apparent effect upon the melting point or hardness of the resulting solid wax. Some of the liquid waxes required a longer hydrogenation time to attain an iodine value of about 1. At this iodine value all of the solid waxes had melting points between 66 and 68°C. Hardness values of all the solid waxes as measured by the Trionic hardness gauge were 90. One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.     

New crop developments for industrial oils

Traditional industrial fats and oils are derived from inedible tallow or lard, fish and whale oil, and a small group of plant oils, including linseed, soybean, castor, tung, tall, and rapeseed oil. A group of new crops and prospective new crops is available to be utilized advantageously for the production of renewable industrial resources. Some of these plants have been studied extensively from germplasm variation through crop production and processing to evaluation of the final oil and meal products. Others are not developed that far yet. Case histories onCramble, Limnanthes, Lunaria (long chain acids),Lesquerella (hydroxy acids),Stokesia andVernonia (epoxy acids),Calendula (conjugated unsaturation),Cuphea (short chain acids), jojoba (liquid wax esters), andFoeniculum (petroselenic acid) indicate that many obstacles must be overcome to arrive at success.     

Chemical structure of long-chain esters from “sansa” olive oil

The major objective of this study was to determine the chemical structure of long-chain esters present in lower-grade olive oil. The classes of esters composing the hexanediethyl ether (99∶1) extract of the wax fraction from a pomace olive oil were: (i) esters of oleic acid with C₁−C₆ alcohols, (ii) esters of oleic acid with long-chain aliphatic alcohols in the range C₂₂−C₂₈ and (iii) benzyl alcohol esters of the very long-chain saturated fatty acids C₂₆ and C₂₈. The analysis and the structure assignments were carried out by gas chromatography coupled with mass spectrometry and by comparison with synthetic authentic model compounds. This work provided precise data on the chemical nature of the wax esters present in olive oil and should represent a means to detect adulteration of higher-grade olive oil with less expensive pomace olive oil and seed oils.