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T1 - Benzene-free synthesis of adipic acid

Adipic acid consumption is linked almost 90% to nylon production by the polycondensation with hexamethylenediamine.

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Adipic Acid for synthesis - ITW Reagents

AB - 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 is used in manufacturing plasticizers and lubricants components.

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 Synthesis - [PDF Document]

Food grade adipic acid is used as gelling aid, acidulant, leavening and buffering agent.

The oxidation of ricinoleic acid produces, by splitting at the level of the double bond and at the level of the OH group, at the same time, suberic acid (octanedioic acid) and the next homologue azelaic acid.
Suberic acid was used in the manufacture of alkyd resins and in the synthesis of polyamides leading to nylon.

It has several industrial uses in the production of adhesives, plasticizers, gelatinizing agents, hydraulic fluids, lubricants, emollients, as an additive in the manufacture of some form of nylon (nylon-6,6), polyurethane foams, leather tanning, urethane and also as an acidulant in foods. Adipic acid is used after esterification with various groups such as dicapryl, di(ethylhexyl), diisobutyl, and diisodecyl.
A graphic chart describing the biosynthesis of adipic acid via omega oxidation may be found on the web site.

Adipic acid for synthesis | VWR

Adipic acid has two carboxylic acid, -COOH, groups, which can yield two kinds of salts.

Most elatomeric polyurethanes are either polyester or polyether based. The soft segments comprise the larger portion of the elastomer and, therefore, determine the physical properties of the elastomer. For example, polyester-based urethane elastomers have better oxidative and high temperature stability than polyether-based polyurethanes, but have lower hydrolytic stability and low-temperature flexibility. However, polyethers are usually more expensive than polyesters.
The cheapest polyether is polypropylene oxide (PPO) polyol, also called polypropylene glycol. Due to the low polarity and high flexibility, even high molecular weight PPG polyols are liquid at room temperature, whereas most polyester polyols are crystalline greases. Another important polyether polyol is based on polytetramethylene oxide (PTMO), sometimes called polytetrahydrofurane (PTHF). Both PTHF and PPO polyols have low melting temperatures and very low Tg's (190 - 200 K). But PTHF has higher strength than PPG, probably due to its ability to crystallize under stress. It is the preferred polyol for the manufacture of elastic urethane fibers such as Spandex (Elastan) for stretchable fabrics.
Many polyester polyols are made from adipic acid and ethylene glycols (polyethylene adipate), or from butanediols and adipic acid (polybutylene adipate). Both diols are crystalline above room temperature. To reduce the Tg and to destroy the crystallinity, copolyesters are often prepared from a mixture of glycols and adipic acid. Another important polyol is polycaprolactone diol. It is a biodegradable polyester with a low melting point of about 330 K and a glass transition temperature of about 210 K. It is sometimes copolymerized to reduce the crystallinity in the caprolactone based oligomer. This diol is mostly used for the manufacture of speciality polyurethanes.

AB - 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.

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  • Benzene-free synthesis of adipic acid — MSU Scholars

    In practical food preservation, the Na salt of benzoic acid is the most widely used form (see ).

  • Adipic acid via oxidation of cyclohexanone - YouTube

    Acyl (-CO) is an organic radical formed by removal of a hydroxyl group from an organic acid (carboxyl group).

  • Clean Alternative for Adipic Acid Synthesis ..

    Dicarboxylic acids are suitable substrates for preparation of organic acids forthe pharmaceutical and food industries.

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Synthesis of Adipic Acid - Almedauniversity

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.

Benzene-free synthesis of adipic acid — Research …

The most important commercial aromatic isocyanates are toluenediisocyanate (TDI), diphenylmethane diisocyanate (MDI), and naphthalene diisocyanate (NDI) and their polymeric forms. Toluene diisocyanate is usually supplied as a mixture of two isomers: 2,4-TDI and 2,6-TDI (see table below).
Pure MDI and TDI are often used for the preparation of thermoplastic elastomers and foams, while MDI and TDI based polyisocyanate are often prefered for coatings, sealants and adhesives.
Aliphatic isocyanate of industrial importance are hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI) and hydrogenated MDI (HMDI). In contrast to aromatic isocyantes, urethanes made with these isocyantes are UV-stable, i.e. do not discolor and are less susceptible to oxydation and degradation. However, they are more expensive. For this reason, aromatic isocyantes are used when oxidative discoloration on exposure to UV radiation is not an issue, whereas aliphatic isocyantes are preferred for more demanding applications, like exterior coatings.
The most important triisocyanate is triphenylmethane triisocyanate. It finds applications in the coating and adhesive industries.

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