Cottonseed-oil processing

The processes responsible for these and other oil product qualities are presented in this section. 

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TABLE 1. Some Important Dates in the Evolution of Cottonseed Oil Processing and Utilization. 

During the cottonseed oil processing when the oil is removed from the cottonseed, some gossypol will also be extracted and remain in the oil, but it can be removed in the subsequent refining process, although some oil is lost. Meanwhile, some gossypol can react with other compounds in the... 

Flow sequences for cottonseed oil processing after extraction for six different product groups are illustrated on Figure 7.1. Extracted and filtered cottonseed oil, still in use in some parts of the world, is omitted from this flowchart. Even in 1998, cottonseed oil purchased in local bazaars in Central Asia had no processing beyond extraction, except possibly a filtration process. Such a product would be unacceptable in the western world where consumers expect edible oil products that are ... 

O Brien, R.D. and Wan, P.J. (2001) Cottonseed oil processing and utilization, in Proceedings World Conference and Exhibition on Oilseed Processing and Utilization (ed R. Wilson), AOCS Press, Champaign, IL, p. 16. 

O Brien, R.D. P.J. Wan. Cottonseed oil Processing and utilization. Proceedings of the World Conference on Oilseed Processing and Utilization R.F. Wilson, Ed. AOCS Press Champaign, IL, 2001 pp. 113-114. 

R. D. O Brien and P. J. Wan, Cottonseed Oil Processing and Utilization, in Proc. World Conf on Oilseed Processing and Utilization, AOCS Press, Champaign, 111., 2001, pp. 90-140. 

The composition of common fats and oils are found in Table 1. The most predominant feedstocks for the manufacture of fatty acids are tallow and grease, coconut oil, palm oil, palm kernel oil, soybean oil, rapeseed oil, and cottonseed oil. Another large source of fatty acids comes from the distillation of cmde tall oil obtained as a by-product from the Kraft pulping process (see Tall oil Carboxylic acids, fatty acids from tall oil). 

The raw materials for the manufacture of soap, the alkali salts of saturated and unsaturated C10-C20 carboxylic acids, are natural fats and fatty oils, especially tallow oil and other animal fats (lard), coconut oil, palm kernel oil, peanut oil, and even olive oil. In addition, the tall oil fatty acids, which are obtained in the kraft pulping process, are used for soap production. A typical formulation of fats for the manufacture of soap contains 80-90% tallow oil and 10-20% coconut oil [2]. For the manufacture of soft soaps, the potassium salts of fatty acids are used, as are linseed oil, soybean oil, and cottonseed oil acids. High-quality soap can only be produced by high-quality fats, independent of the soap being produced by saponification of the natural fat with caustic soda solution or by neutralization of distilled fatty acids, obtained by hydrolysis of fats, with soda or caustic soda solutions. Fatty acids produced by paraffin wax oxidation are of inferior quality due to a high content of unwanted byproducts. Therefore in industrially developed countries these fatty acids are not used for the manufacture of soap. This now seems to be true as well for the developing countries. 

Seven diets were constructed from purified natural ingredients obtained from either C3 (beet sugar, rice starch, cottonseed oil, wood cellulose, Australian Cohuna brand casein, soy protein or wheat gluten for protein) or C4 foodwebs (cane sugar, corn starch, com oil, processed corn bran for fiber, Kenya casein for protein) supplemented with appropriate amounts of vitamins and minerals (Ambrose and Norr 1993 Table 3a). The amino acid compositions of wheat gluten and soy protein differ significantly from that of casein (Ambrose and Norr 1993). 

Skeletal catalysts are usually employed in slurry-phase reactors or fixed-bed reactors. Hydrogenation of cottonseed oil, oxidative dehydrogenation of alcohols, and several other reactions are performed in sluny phase, where the catalysts are charged into the liquid and optionally stirred (often by action of the gases involved) to achieve intimate mixing. Fixed-bed designs suit methanol synthesis from syngas and catalysis of the water gas shift reaction, and are usually preferred because they obviate the need to separate product from catalyst and are simple in terms of a continuous process. 

In processing most oilseeds, hexane is stripped from the miscella by distillation to produce a crude oil that subsequently is alkali or physically refined. However, gossy-pol and other pigments become extremely difficult to bleach if left in warm cottonseed oil for more than a few days. It is normal practice for cottonseed oil mills to send their crude oil immediately to an alkali refinery or to operate an on-site miscella refinery, where phosphatides, FFA, and color pigments are removed by alkali treatment of the oil-extraction solvent mixture. Cooling the crude oil as produced, until refining, also slows fixing of color. 

Krishnaiah and Sarkar investigated the effect of chromia on the activity and selectivity of 25% Ni-Si02 in the hydrogenation of cottonseed oil (palmtic 22.5, stearic 3.5, oleic 22.5, and linoleic 16.5 mol%) at 120-140°C and 0.5-1 MPa H2.98 Chromia was found to suppress the stearate formation completely with its optimum content of 0.17 Cr/Ni atomic ratio. The kinetics of the process was found to be first-order with respect to linoleate and half order with respect to hydrogen. 

A case study of the hydrogenation of cottonseed oil is made by Rase Chemical Reactor Design for Process Plants, vol. 2, Wiley, 1977, pp. 161-178). 

Steam used to recover oil from earth Chemists learned that FFA level in crude cottonseed oil was a good quality indicator Removed the objectionable flavors and odors from the oil Process to convert a liquid oil to a semi-solid... 

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