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排序方式: 共有356条查询结果,搜索用时 15 毫秒
1.
Alternative hydrocarbon solvents for cottonseed extraction 总被引:3,自引:0,他引:3
P. J. Wan D. R. Pakarinen R. J. Hron Sr. O. L. Richard E. J. Conkerton 《Journal of the American Oil Chemists' Society》1995,72(6):653-659
Hexane has been used for decades to extract edible oil from cottonseed. However, due to increased regulations affecting hexane
because of the 1990 Clean Air Act and potential health risks, the oil-extraction industry urgently needs alternative hydrocarbon
solvents to replace hexane. Five solvents,n-heptane, isohexane, neohexane, cyclohexane, and cylopentane, were compared with commercial hexane using a benchscale extractor.
The extractions were done with a solvent to cottonseed flake ratio of 5.5 to 1 (w/w) and a miscella recycle flow rate of 36
mL/min/sq cm (9 gal/min/sq ft) at a temperature of 10 to 45°C below the boiling point of the solvent. After a 10-min single-stage
extraction, commercial hexane removed 100% of the oil from the flakes at 55°C; heptane extracted 100% at 75°C and 95.9% at
55°C; isohexane extracted 93.1% at 45°C; while cyclopentane, cyclohexane, and neohexane removed 93.3, 89.4, and 89.6% at 35,
55, and 35°C, respectively. Each solvent removed gossypol from cottonseed flakes at a different rate, with cyclopentane being
most and neohexane least effective. Based on the bench-scale extraction results and the availability of these candidate solvents,
heptane and isohexane are the alternative hydrocarbon solvents most likely to replace hexane.
Presented in part at the AOCS Annual Meeting & Expo, Atlanta, Georgia, May 1994. 相似文献
2.
A novel technique for the preparation of secondary fatty amides 总被引:1,自引:0,他引:1
Alexander Bilyk Raymond G. Bistline Jr. George J. Piazza Stephen H. Feairheller Michael J. Haas 《Journal of the American Oil Chemists' Society》1992,69(5):488-491
A technique for the synthesis of monosubstituted fatty amides at low temperature and ambient pressure was developed. This
method involved the condensation of an amine with a triacylglycerol. The primary amine (ethyl,n-butyl,n-hexyl andn-octyl were tested) acted as reagent and solvent for the fatty substrates. No additional organic solvent or catalyst was added.
Tallow, vegetable oils and fish oil all served well as substrates, as did pure tripalmitin. The rate of amidation was dependent
upon temperature and the ratio of fat to amine. In a series of experiments conducted with tallow andn-butylamine at a fat:amine molar ratio of 1:16, amidation could be carried out at 20°C, producingn-butyltallowamide in 83% yield in 24 hr. When the fat:amine molar ratio was reduced to 1:8, and the temperature raised to
45°C, the amide yield was 87.6% in 24 hr. When the reaction was carried out at the boiling point ofn-butylamine (78°C) and at a fat:amine ratio of 1:8, the amide yield was 93.2% in 4 hr. The reaction progressed more rapidly
with higher molecular weight amines. The identity and purity of the amides was assessed by thin-layer chromatography and confirmed
by elemental analyses and infrared and C13 nuclear magnetic resonance spectroscopy. 相似文献
3.
P. J. Wan R. J. Hron Sr. M. K. Dowd M. S. Kuk E. J. Conkerton 《Journal of the American Oil Chemists' Society》1995,72(6):661-664
Hexane has been used for decades to extract oil from cottonseed and is still the solvent of choice for the edible-oil industry.
Due to increased regulations as a result of the 1990 Clean Air Act and potential health risks, the edible-oil extraction industry
urgently needs an alternate hydrocarbon solvent to replace hexane. Based on laboratory-scale extraction tests, two hydrocarbon
solvents, heptane and isohexane, were recommended as potential replacements for hexane. A cottonseed processing mill with
a 270 MT/day (300 tons/day) capacity agreed to test both solvents with their expander-solvent process. Extraction efficiencies
of isohexane and heptane, judged by extraction time and residual oil in meal, refined and bleached color of miscella refined
oil, and solvent loss, were comparable to that of hexane. However, fewer problems were encountered with the lower-boiling
isohexane than with the higher-boiling heptane. With isohexane, the daily throughput increased more than 20%, and natural
gas consumption decreased more than 40% as compared to hexane. 相似文献
4.
L. deMan V. D’Souza J. M. deMan B. Blackman 《Journal of the American Oil Chemists' Society》1992,69(3):246-250
A number of North American vegetable and animal fat shortenings, which had been analyzed previously for their physical and
textural characteristics, were analyzed also for their chemical composition. The fatty acid and triglyceride composition of
the solids were calculated by analyzing the composition of the original product and the liquid phase, and by determination
of the solid fat content (SFC) of the fat. The solids were also isolated by isopropanol (IP) separation, and the high melting
glycerides (HMG) by acetone crystallization at 15°C. There was not much difference in total saturates andtrans content between vegetable and animal fat shortenings. Changing formulations from soy-palm to soy-cottonseed does not change
the total saturates plustrans content. The solids of the vegetable shortenings in the β form contained about 20% of 16:0, those in the β′ form 30% or more.
The animal fat shortenings were mainly in the β form, their solids contained 30% or more of 16:0. C54 triglyceride content
of the solids of β vegetable shortenings (calculated and IP-separated) was >45%, that of all animal fats was <25%. Solids
of animal fat shortenings contain high levels of C52. The C54 triglycerides are β-tending and should be kept low in vegetable
shortening. In the HMG the C54 should not exceed 30%. This can only be achieved by incorporation of a β′ hard fat, preferably
palm hard fat. Animal fat, especially lard, crystallizes in the β form because the palmitic acid in the glyceride molecule
is located in the 2-position, whereas those of vegetable fats are in the 1- and 3-position. 相似文献
5.
Ethanol vapor deactivation of gossypol in cottonseed meal 总被引:3,自引:0,他引:3
R. J. Hron Sr. P. J. Wan M. S. Kuk 《Journal of the American Oil Chemists' Society》1996,73(10):1337-1339
Most cottonseed cultivars contain gossypol, a polyphenolic antinutritional compound. “Free” gossypol is a physiologically
active form of gossypol, which is toxic to young- and nonruminant animals. To utilize solvent-extracted cottonseed meal as
a general feed, gossypol must be either removed or deactivated to a minimum level specified for each class of animal. Normally,
deactivation is carried out prior to oil extraction; however, the desired level of deactivation is not always attained. A
new supplemental method of deactivation has been found by using either ethanol or isopropanol vapors on solventextracted meal.
In a bench-top set-up, ethanol vapor reduced free gossypol from 0.115 to 0.053%, and a further reduction to 0.026% has been
observed with the addition of ferrous sulfate. The supplemental deactivation method can, in most cases, reduce free gossypol
to significantly safer levels for feeding, thus increasing utility, and possibly demand, for cottonseed meal as a general
animal feed protein source.
Presented in part at the AOCS Annual Meeting, Atlanta, GA, May 8–12, 1994. 相似文献
6.
C. Kapseu G. J. Kayem D. Balesdent L. Schuffenecker 《Journal of the American Oil Chemists' Society》1991,68(2):128-130
Cold fractionation of cottonseed oil is made difficult by the high viscosity of the oil. This study was aimed at demonstrating
the effect of solvents on the viscosity of mixtures between 0°C and 25°C with a view to facilitating the fractionation of
refined cottonseed oil. The solvents used were acetone, methylethylketone, methylisobutylketone, hexane and heptane. Measurements
of viscosity were carried out by means of a capillary viscometer. The ratio of the viscosity of cottonseed oil to that of
pure solvents is of the order of 300. The viscosities of solutions of various ratios of solvent to oil (1/3, 1/1, 3/1) are
between those of cottonseed oil and the pure solvents. The effect of the solvent/oil ratio overrides that of solvent nature.
The effect of solvent in reducing the viscosity of cottonseed oil is by descending order: acetone, hexane, methylethylketone,
heptane, methylisobutylketone. 相似文献
7.
Ethanol extraction of oil,gossypol and aflatoxin from cottonseed 总被引:7,自引:0,他引:7
R. J. Hron Sr. M. S. Kuk G. Abraham P. J. Wan 《Journal of the American Oil Chemists' Society》1994,71(4):417-421
Commercial processing of cottonseed requires hexane to extract and recover edible oil. Gossypol and aflatoxin are not removed
from extracted meals. A bench-top extraction process with 95% (vol/vol) aqueous ethanol (EtOH) solvent has been developed
that extracts all three of the above materials with a much less volatile solvent. In this process, cottonseed is pretreated
and extracted with ambient 95% EtOH to remove gossypol and then extracted with hot 95% EtOH to extract oil and aflatoxin.
Membranes and adsorption columns are used to purify the various extract streams, so that they can be recycled directly. A
representative extracted meal contained a total gossypol content of 0.47% (a 70% reduction) and 3 ppb aflatoxin (a 95% reduction).
Residual oil content was approximately 2%. Although the process is technically feasible, it is presently not economical unless
a mill has a continual, serious aflatoxin contamination problem. However, if a plant cannot meet the hexane emission standards
under the Clean Air Act of 1990, this process could provide a safer solvent that may expand the use and increase the value
of cottonseed meal as a feed for nonruminants.
Presented in part at the AOCS annual meeting, Toronto, Canada, May 1992. 相似文献
8.
M. -K. Chang G. Abraham V. T. John 《Journal of the American Oil Chemists' Society》1990,67(11):832-834
Cocoa butter-like fat was prepared from completely hydrogenated cottonseed and olive oils by enzymatic interesterification.
The optimum reaction time to produce the major-component of cocoa butter, 1(3)-palmitoyl-3(1)-stearoyl-2-monoolein (POS),
was 4 hr. The cocoa butter-like fat was isolated from the reaction mixture by two filtration steps. The yield of cocoa butter-like
fat was 19%, based on the weight of the original oils. Chromatographic analysis of the product by reversephase high-performance
liquid chromatography (HPLC) has shown it contains triglyceride components similar to those of cocoa butter, but that it has
slightly more diglycerides. The melting point of this product, as measured by a differential scanning calorimeter, is 39°C,
which compares well to the 36°C melting point of natural cocoa butter.
Presented in part at the AOCS meeting in Cincinnati, Ohio, in 1989. 相似文献
9.
以三氟乙酸为显色剂,对芝麻香油、二级棉籽油、三级棉籽油、一级菜籽油、菜籽毛油5种植物油进行显色反应,并在350~700 nm波长进行紫外-可见光谱扫描.结果显示用三氟乙酸做显色剂能够很明显地将这5种植物油区分开来,所显示的颜色分别为:黄绿色、黄橙色、暗红橙色、红紫色、暗红橙色;并且上述5种植物油显色反应后的紫外-可见光谱扫描曲线差别很大,容易区分. 相似文献
10.
Zhongqi He Dorselyn C. Chapital H.N. Cheng Olanya O. Modesto 《Journal of Adhesion Science and Technology》2016,30(19):2109-2119
The interest in natural product-based wood adhesives has been steadily increasing due to the environmental and sustainable concerns of petroleum-based adhesives. In this work, we reported our research on the utilization of water-washed cottonseed meal (WCM) as wood adhesives. The adhesive strength and water resistance of WCM adhesive preparations on poplar, Douglas fir, walnut, and white oak wood veneers were tested with press temperatures of 80, 100, and 130 °C. Our data indicated that raising the hot press temperature from 80 to 100–130 °C greatly increased the bonding strength and water resistance of the WCM adhesives. The general trend of the adhesive strength of WCM on the four wood species was Douglas fir > poplar ≈ white oak > walnut. The rough surface of Douglas fir with tipping features could enhance the mechanical interlocking between the wood fibers and adhesive slurry, contributing to the high adhesive strength. The dimensional swelling of the bonded wood pairs due to water soaking was in the order: thickness > width (i.e. perpendicular to the wood grain) > length (i.e. parallel to the wood grain). The greatest dimensional changes were observed in Douglas fir specimens. However, the highest decrease in adhesive strength by water soaking was with poplar wood specimens. These observations suggested that the wood dimensional changes were not dominant factors on water weakening the bonding strength of these wood pairs. 相似文献