Alkali-refining continuous

The recovery of fatty acids from soapstocks by a continuous process has been described soapstocks obtained from degumming and alkali refining operations are subjected to a saponification step followed by controlled acidification for cost efficiency and pollution control.Ila,b... 

Both alkali and physical refining have been used for FFA removal (5). With alkali refining, batch or continuous methods may be used. Oil may be pretreated with phosphoric or organic acid for phospholipid hydration. The oil is then treated with 16-30 baume (Be ) caustic with 20-40% excess. The soaps settle and may be recovered as soapstock or foots (47). 

While physical refining will continue to receive attention, aUcah refining is likely to continue to be the preferred choice where soapstock disposal issues can be resolved economically. Unlike some physical refining systems, alkah refining allows the processor to properly prepare almost any type (and any condition) of oil to produce a quality product. Alkali refining introduces its special set of maintenance, environmental, and neutral oil loss issues for which the processor must continually be alert. 

In 1985, ANPA came out with the first-generation soybean-oil-based lithographic news ink, comprised of alkali-refined soybean oil, hydrocarbon resin, carbon black pigment, and an antioxidant (Moynihan, 1985a). This black ink had similar printing properties to mineral-oil-based inks, but cost 30—50% more. The color inks were formulated in a similar way, had good print quality, but cost about 5—10% more than the petroleum-based commercial inks. Thus, industry continued to search for 100% vegetable-oil-based inks to replace petroleum-based inks. 

Alkali refining is also carried out in a semi-continuous manner, the Zenith Process (Young, 1981). In this process small batches of oil are measured and treated with phosphoric acid in a pretreatment unit. From this unit the oil is pumped continuously via a centrifuge which removes dirt and denatured phosphatides to one of two neutralizer vessels which are used alternately. The oil enters the... 

Degumming is a treatment with water (steam), which is mainly carried out with oils of high phospholipid content, e.g., soybean oil.(- lecithin). Alkali-refining is used to eliminate ffa. Almost all edible oils are processed in continuous plants today. The added NaOH forms salts, and the soap-stock ( foots ) is separated in a centrifuge from the oil, which is then washed and dried. Soapstock is a low-cost, valuable source for fatty acids. Steam-refining is done to remove the ffa by steam- distillation. 

A consideration of natural occurrence and chemical composition of alkali zeolites allows a certain refinement of the zeolite facies concept previously proposed. The key factor is the grouping of the alkali zeolites into a continuous solid solution series. Other possible coexisting phases of similar composition are sodium and potassium feldspar, natrolite and analcite. The extent of solid solution decreases with temperature, possibly also with pressure. This effect allows the sequential series zeolite-K feldspar, zeolite-analcite-K feldspar, analcite-K feldspar-albite and eventually two feldspars to the exclusion of analcite, the alkali zeolite with the highest stability limits. 

Meade (26), who made use of an alkali metal alkoxide as a catalyst at 100°C at atmospheric and shghtly above atmospheric pressure. Further refinement was made by Tesoro (27), who conducted the reaction at 55-75°C and a vacuum of 4—8 kPa. Schurman (28) patented a continuous process for making alkanolamide, which makes use of a thin film reactor. It is claimed the short contact time in the reactor produces a high-purity alkanolamide (29). 

Obtained by solvent extraction using petroleum hydrocarbons, or to a lesser extent by expression using continuous screw-press operations, of the seeds of either Glycine max (Leguminosae) or Glycine soja (Leguminosae). The oil is refined, deodorized, and clarified by filtration at about 0°C. Any phospholipids or sterols present are removed by refining with alkali. 

Adachi, T. Ohnuki, M. Yoshida, N. Sonobe, T. Kawamura, W. Takeishi, H. Gunji, K. Kimura, T. Suzuki, T. Nakahara, Y. Muromura, T. Kobayashi, Y. Okashita, H. Yamamoto, T. (1990). Dissolution Study of Spend PWR Fuel Dissolution Behavior and Chemical Properties of Insoluble Residues. Journal of Nuclear Materials, Vol. 174, No. 1, (November 1990), pp. 60-71, ISSN 0022-3115 Anderson, H. H. (1949). Alkali Plutonium(IV) Nitrates, In The Transuranium Elements, National Nuclear Energy Series IV, Vol. 14B, G. T. Seaborg, J. J. Katz, W. M. Manning, (Eds.), pp. 964-967, McGraw-Hill Book Co. Inc., New York, USA Ebert, K Henrich, E. Stahl, R. Bauder, U. (1989). A Continuous Crystallization Process for Uranium and Plutonium Refinement, Proceedings of 2nd International Conference on Separation Science Technology, pp. 346-352, Paper No. S5b, Hamilton, Ontario, Canada, October 1-4,1989... 

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