Adipic acid, metal salts

Salt Formation. Salt-forming reactions of adipic acid are those typical of carboxylic acids. Alkali metal salts and ammonium salts are water soluble alkaline earth metal salts have limited solubiUty (see Table 5). Salt formation with amines and diamines is discussed in the next section. 

The thermal decarboxylation of a mixture of barium salts has been used to prepare unsymmetrical ketones the yields are not stated. The earlier procedure has been modified by carrying out the reaction in vacuo in an iron flask. Glass reaction vessels are inferior. In this manner, a large number of the high-molecular-weight methyl ketone s, C9, C,o, C,j-C , and C, are prepared in 54-67% yields. Cyclopentanone has been synthesized in 80% yield by distillation of adipic acid from barium hydroxide at 295°. In a study of metallic oxides and carbonates, magnesium oxide is preferred for the liquid-phase ketonization of stearic acid at 330-360° (95%). A convenient method for the preparation of dibenzyl ketone is the reaction of phenylacetic acid, acetic anhydride. 

The mixture of cyclohexanone and cyclohexanol can be converted to adipic acid in a second step by oxidation with nitric acid in the presence of metal compounds such as Cu or salts as homogeneous catalysts. 

Various metal ions and complexes have been used to promote the catalytic air oxidation of hydrocarbons. There are some classical reactions that have developed into commercial processes, like the oxidation of n-butane to acetic acid, the oxidation of cyclohexane to adipic acid, or of p-xylene to terephthalic acid, all of which utilize cobalt salts as catalysts. 

Rotomolding additives include nucleating agents, such as, inoiganic substances such as talcum, metal oxides such as titanium dioxide or magnesium oxide, phosphates, carbonates or sulfates of, preferably, alkaline earth metals organic compounds such as mono- or polycarbojQ lic acids and their salts, e g., 4-tert-butylbenzoic add, adipic acid, diphenylacetic acid, sodium succinate or sodium benzoate polymeric compounds such as ionic copolymers (ionomers). ... 

Metal salts, such as sodium and potassium, of adipic, and terephthallc, etc., acids are largely insoluble in such organic liquids as chloroform and carbon tetrachloride. Our initial attempts were directed at neutralizing diacids employing triethylamine as the neutralizing base. The resulting ditriethylammonium salt yielded a sparsely soluble product. For instance ditriethylammonium terephthalate is partially soluble in chloroform... 

Additives used in final products Plasticizers acetyl tri-n-butyl citrate, epoxidized soybean oil, polymeric condensation product of azelic acid and 1,3-butane-diol, polymeric plasticizer of adipic acid and propylene glycol. Antistatics ionic polymer, imidazoline/metal salt ... 

Adipic acid, benzoic acid, or metal salts of these acids, sorbitols, such as 3,4-dimethylbenzylidene sorbitol are examples of nucleating agents, as are many inorganic fUlers (1). Classes of nucleating agents and special examples are given in Table 12.1. 

Metal-catalyzed liquid-phase auto-oxidahon plays a critical role in the manufacture of monomers widely used in polymers such as nylon and polyester. As menhoned earlier, soluble salts of cobalt and manganese catalyze oxidation of cyclohexane by dioxygen to cyclohexanol and cyclohexanone. Cyclohexanol and cyclohexanone are oxidized by nitric acid to give adipic acid, one of the monomers of nylon 6,6. The oxidation by nitric acid is carried out in the presence of and ions to improve... 

In the autoxidation of neat hydrocarbons, catalyst deactivation is often due to the formation of insoluble salts of the catalyst with certain carboxylic acids that are formed as secondary products. For example, in the cobalt stearate-catalyzed oxidation of cyclohexane, an insoluble precipitate of cobalt adipate is formed. 18fl c Separation of the rates of oxidation into macroscopic stages is not usually observed in acetic acid, which is a better solvent for metal complexes. Furthermore, carboxylate ligands may be destroyed by oxidative decarboxylation or by reaction with alkyl hydroperoxides. The result is often a precipitation of the catalyst as insoluble hydroxides or oxides. The latter are neutralized by acetic acid and the reactions remain homogeneous. 

Effervescents comprise a soluble organic acid and an alkali metal carbonate salt. Citric acid is most commonly used for its flavor-enhancing properties. Malic acid imparts a smoother after taste and fumaric, ascorbic, adipic, and tartaric acids are less commonly used [14], Sodium bicarbonate is the most common alkali, but potassium bicarbonate can be used if sodium levels are a potential issue with the formulation. Both sodium and potassium carbonate can also be employed. Other excipients include water-soluble binders such as dextrose or lactose, and binder levels are kept to a minimum to avoid retardation of disintegration. All ingredients must be anhydrous to prevent the components within the formulation reacting with each other during storage. 

Salty tastes are exhibited almost exclusively by some inorganic salts (especially halides, sulfates, phosphates, nitrates and carbonates of alkali metals, alkaline earth metals and ammonium salts). Salty tastes combined with other tastes are also shown by some salts of carboxylic acids (salts of formic, acetic, succinic, adipic, fumaric, lactic, tartaric and citric acids), amino acids (such as salts of glutamic acid and chohne) and some oligopeptides. 

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