Decolorization and deodorization

Vegetable oils are refined through pressing/extraction, degumming, alkali deacidification, decolorization, and deodorization. Alkali deacidification byproduces soapstock. Acidulation of soapstock prepares acid oil which contains FFAs, acylglycerols, and other lipophilic compounds. It is reproduced currently as FFAs, which are used as raw materials for production of soaps, lubricants, and paints. But the demand for FFAs is almost in saturation. Hence, conversion of acid oil to BDF is expected to avoid an oversupply of the industrial FFAs and subsequent price decrease. 

The USP 28 describes lanolin as the purified wax-like substance obtained from the wool of the sheep, Ovis aries Linne (Earn. Bovidae), that has been cleaned, decolorized, and deodorized. It contains not more than 0.25% w/w of water and may contain up to 0.02% w/w of a suitable antioxidant the PhEur 2005 specifies up to 200 ppm of butylated hydroxytoluene as an antioxidant. 

Use Production of aluminum potassium compounds, millstones, substitute for bauxite in aluminum manufacture, decolorizing and deodorizing agent, fertilizer. 

Use Most important ore of aluminum, aluminum chemicals, abrasives, aluminous cement, refractories, decolorizing and deodorizing agent, catalysts, filler in rubber, plastics, paints, cosmetics, hydraulic fracturing. 

The conventional procedure for removing the impurities involves three steps—neutralization, decolorization, and deodorization. The refining may include a preliminary washing of the oil with warm water, which is reported to remove proteins and gummy substances. 

Because of this feature, some soaps and detergents that cannot be satisfactorily treated with carbon in aqueous solution can be effectively decolorized and deodorized in a solvent in which they do not assume a colloidal form. 

At the time the first edition of this text was prepared, many envisioned that large markets would result from studies of adsorption-desorption processes in the manufacture of biochemicals. The markets have not developed but the potential still exists. Activated carbon is extensively employed for the decolorizing and deodorizing of many biochemicals but we lack information as to specific applications. 

Uses in hair bleaches as an oxidizer and bleacher decolorizing and deodorizing oils, in electroplating, in making soluble starch reducer and retarder in photography in yeast treatment in analytical chemistry. ABCD. UCU A... 

Activated carbon is applied in the first place as adsorbent for water purification and for gas/air purification. Production streams in the chemical, pharmaceutical and food industry are purified for decolorization and deodorization etc. Recovery of the adsorbates by desorption brings a number of other applications. Known examples are the recovery of solvents in solvent recovery installations and the recovery of gold in mines. Activated carbon is not only applied as an adsorbent. It is also used as a catalyst for a limited number of reactions and as a catalyst carrier. As catalyst carrier activated carbon is among others applied as support for precious metals. These catalysts are mainly applied in the fine chemical and in the pharmaceutical industry. Nevertheless a limited number of precious metal catalyst applications for the bulk chemical industry is known. Not only precious metal catalysts based on activated carbons are produced. A hmited number of other catalytic active compounds are supported by activated carbon. 

Acid-activated clay - This is calcium bentonite that has been treated with sulfinic or hydrochloric acid to exchange calcium widi hydrogen ions, to dissolve carbonate impurities, to leach some tetrahedral aluminum and octahedral magnesium, aluminum, and iron, and to delaminate the edges of the stacks of clay platelets. The overall effect is to increase porosity and surface area and, thereby, the cl s absorptive properties. This type of bentonite is used primarily to decolorize and deodorize petroleum and edible oils. 

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