The preparation of adipic acid by Ivy Liao on Prezi
The adipic acid ending up in the final product after
simple distillation is most likely due to the fact that distillation is a
closed system and therefore pressure sensitive.
26/11/2013 · The preparation of adipic acid NMR ..
N2 - Strains of Escherichia coli were constructed and evaluated that synthesized cis,cis-muconic acid from D-glucose under fed-batch fermentor conditions. Chemical hydrogenation of the cis,cis-muconic acid in the resulting fermentation broth has also been examined. Biocatalytic synthesis of adipic acid from glucose eliminates two environmental concerns characteristic of industrial adipic acid manufacture: use of carcinogenic benzene and benzene-derived chemicals as feedstocks and generation of nitrous oxide as a byproduct of a nitric acid catalyzed oxidation. While alternative catalytic syntheses that eliminate the use of nitric acid have been developed, most continue to rely on petroleum-derived benzene as the ultimate feedstock. In this study, E. coli WN1/pWN2.248 was developed that synthesized 36.8 g/L of cis,cis-muconic acid in 22% (mol/mol) yield from glucose after 48 h of culturing under fed-batch fermentor conditions. Optimization of microbial cis,cis-muconic acid synthesis required expression of three enzymes not typically found in E. coli. Two copies of the Klebsiella pneumoniae aroZ gene encoding DHS dehydratase were inserted into the E. coli chromosome, while the K. pneumoniae aroY gene encoding PCA decarboxylase and the Acinetobacter calcoaceticus catA gene encoding catechol 1,2-dioxygenase were expressed from an extrachromosomal plasmid. After fed-batch culturing of WN1/pWN2.248 was complete, the cells were removed from the broth, which was treated with activated charcoal and subsequently filtered to remove soluble protein. Hydrogenation of the resulting solution with 10% Pt on carbon (5% mol/mol) at 3400 kPa of H2 pressure for 2.5 h at ambient temperature afforded a 97% (mol/mol) conversion of cis,cis-muconic acid into adipic acid.
Adipic acid has been incorporated into controlled-release tablets to obtain a pH-independent release for both weakly basic and weakly acidic drugs. It has also been incorporated into polymeric coatings of hydrophilic monolithic systems to modulate the pH, resulting in zero-order release of a hydrophilic drug.
cyclohexanone and n-hexane to adipic acid.
Adipic acid is an organic compound with the formula (CH2)4(COOH)2. It is the most important of the dicarboxylic acids from the industrial perspective. Approximately 2.5 billion kilograms of this white crystalline powder are produced annually, predominantly as a precursor for the production of nylon 66. Adipic acid rarely occurs in nature.
Synthesis of Adipic Acid by Oxidation of Cyclohexanol - ISASF
In foods, small but significant amounts of adipic acid are used as a food ingredient as a flavorant and gelling aid. It is used in some calcium carbonate antacids to make them tart.
Synthesis of Adipic Acid - Chempedia - LookChem
Co-production of nitrocyclohexane and adipic acid by light-driven nitric acid (HNO3) nitration–oxidation of cyclohexane in an aqueous biphasic system was designed as a potential method for safe synthesis, because the reaction can be carried out at mild conditions (1 atmosphere, 298 K, and solvent-free media). In this process, we find that ultraviolet (UV) irradiation (λ = 365 nm) of a cyclohexane/HNO3 mixture in a N2 atmosphere efficiently produces nitrocyclohexane and adipic acid with total selectivity (ca. 87 %) at a 22 % conversion rate. Nitration–oxidation of cyclohexane is initiated by an ·OH from the direct photolysis of nitric acid. A reaction scheme has been proposed to explain the process and the different concentrations of nitric acid involved with the formation of the different reaction products.
7 Oxidation of a Secondary Alcohol: Cyclohexanone from ..
The majority of the 2.5 billion kg of adipic acid produced annually is used as a monomer for the production of nylon by a polycondensation reaction with hexamethylene diamine forming 6,6-nylon. Other applications include some Polyurethanes. Esters of Adipic Acid, such as DOA (Di-2-Ethylhexyl Adipate) are used as plasticizers for PolyVinyl Chloride (PVC) resins.
Synthesis and Purification of Cyclohexanone ..
Almost 90 percent of adipic acid produced is used in the production of nylon 66. The nylon, which has a protein-like structure, is further processed into fibers for applications in carpeting, automobile tire cord, and clothing. Adipic acid is also used to manufacture plasticizers and lubricant components.