Vegetable fatty acids

The fatty polyamides are produced by reacting di- and polyfunctional amines with polybasic acids that result from condensations of unsaturated vegetable oil acids. The most commonly used amines are ethylene diamine and diethylene triamine. The dicarboxylic acids are synthesized by heating mixtures of unsaturated vegetable fatty acids. The starting materials may come from linseed, soybean, or tung (also called China wood) oil. The fatty acids are heated for several hours at 300°C. If a catalyst is used, the heating is done at a lower temperature. After condensation, the volatile fractions are removed by vacuum. The residues, called dimer acids, are then condensed with the amines. A formation of one such dimer acid from linoleic acid can be illustrated as follows ... 

An important vegetable fatty acid, mainly confined to seed fats of the families Cruciferae and Tropaelaceae (e.g. rape, mustard and wallflower seeds). Mp 33.5°. Chloride Mp 14°. 

Scheme 4.20 Synthesis of diacids and diamines from vegetable fatty acid methyl...

In addition, biotech processes are also efficient in order to perform chemical modifications of vegetable fatty acids such as regioselective hydroxylation. Glycerol can also be used as feedstock in fermentation processes and lead to the production of chemicals of interest. More efforts could be developed to perform the depolymerization of lignin by biochemical ways. 

Sulfolane, another highly polar solvent, is used to separate aromatic hydrocarbons from aliphatic hydrocarbons [10]. The extraction process first developed by Shell Oil in 1959 and which is referred to as the Sulfolane process is used worldwide. The solvency of sulfolane for certain fatty acids and fatty acid esters is the basis for upgrading animal and vegetable fatty acids used in food products, paints, plastics, resins, and soaps. Aqueous solutions containing 30-70 wt% sulfolane are used to remove lignin from wood chips [11]. Sulfolane is used to remove acidic components like hydrogen sulfide and carbon dioxide from gas feed stocks. 

Scheme 16.15. Some vegetable fatty acids used in alkyd resins.

Natural soaps are the sodium and potassium salts of fatty acids. They are produced as a result of the interaction of a caustic alkali and a fat. A typical animal or vegetable fatty acid molecule consists of a long hydrocarbon chain with a terminal carboxyl group. For example in the case of sodium stearate, which was introduced as an example in section 1.6, the fatty acid is stearic acid and it has the chemical formula CH3(CH2)i6COOH. The chemical reaction of stearic acid and sodium hydroxide results in the soap sodium stearate, Ci7H35COO Na+. The commonly occurring fats are lauric, myristic, palmitic, stearic, oleic, etc. Common bars of washing soap will consist of a number of pure soaps. 

Unsaturated fatty acids produced by the hydrolysis of triglycerides can be saturated by hydrogenation in batch or continuous processes. The catalysts already described for triglyceride hydrogenation can be used. Operation is at 160-180°C and 25 atm pressure for vegetable fatty acids and up to 190-200 C for tallow and fish oil fatty acids. The use of higher hydrogen pressures not only increases the rate of reaction and limits the attack of the add on the catalyst but provides better reaction conditions. The catalyst dose is about 0.2% nickel catalyst to oil treated. 

Chem. Descrip. Poiyunsat. vegetable fatty acids conjugated Uses Detergents soap making resins lubricants Properties Acid no. 198-203 iodine no. 129-136 (Woburn) sapon, no, 198-204 Prifac 8968 [Croda Inc]... 

Chem. Descrip. mixed vegetable fatty acid Uses Raw material for detergents and soaps... 

Chem. Descrip. Polyunsaturated vegetable fatty acid Uses Surfactant taw material... 

Chem. Descrip. vegetable fatty acid Uses Raw material for detergents and soaps Properties Lovibond 5 1/4" 15Y/4R acid no. 200-208 iodine no. 50-65 Radiacid 0466 [Oieon NV]... 

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