Phenol catalytic oxidation

Obtained synthetically by one of the following processes fusion of sodium ben-zenesulphonate with NaOH to give sodium phenate hydrolysis of chlorobenzene by dilute NaOH at 400 C and 300atm. to give sodium phenate (Dow process) catalytic vapour-phase reaction of steam and chlorobenzene at 500°C (Raschig process) direct oxidation of cumene (isopropylbenzene) to the hydroperoxide, followed by acid cleavage lo propanone and phenol catalytic liquid-phase oxidation of toluene to benzoic acid and then phenol. Where the phenate is formed, phenol is liberated by acidification. 

Reaction of phenyl metaborate with formaldehyde, followed by catalytic oxidation, has been reported to give sahcylaldehyde selectively and directiy from phenol without isolation of any intermediate products (63). 

Benzene is alkylated with propylene to yield cumene (qv). Cumene is catalytically oxidized in the presence of air to cumene hydroperoxide, which is decomposed into phenol and acetone (qv). Phenol is used to manufacture caprolactam (nylon) and phenoHc resins such as bisphenol A. Approximately 22% of benzene produced in 1988 was used to manufacture cumene. 

The hydroxyl group of the resulting phenol is situated immediately adjacent to where the carboxyl group was previously located. This same Hquid-phase copper oxidation process chemistry has been suggested for the production of cresols by the oxidation of toluic acids. y -Cresol would be formed by the oxidation of either ortho or para toluic acids a mixture of 0- and -cresols would be produced from y -toluic acid (6). A process involving the vapor-phase catalytic oxidation of benzoic acid to phenol has been proposed, but no plants have ever been built utilizing this technology (27). 

Formaldehyde is prepared industrially (for the manufacture of phenol-formaldehyde resins) by the catalytic oxidation of methanol ... 

For the organic contaminants, the required bromine product quality wilt also be site specific. If the catalytic oxidation unit is dedicated to a single bromination process, phase separation and drying may be the only purification required. Contaminants in the recovered bromine which are either the starting materials or products of the original bromination reaction should not present a problem if present in bromine recycled to the bromination reactor. In this case, the catalytic reactor would be operated to minimize the formation of undesirable brominated byproducts. For example, if phenol is present in the waste HBr from a tribromo-phenol manufacturing process, minor tribromophenol contamination of the bromine recycled to the reactor should not be a problem. Similarly, fluorobenzene in bromine recycled to a fluorobenzene bromination process should not present a problem. 

One of the exciting results to come out of heterogeneous catalysis research since the early 1980s is the discovery and development of catalysts that employ hydrogen peroxide to selectively oxidize organic compounds at low temperatures in the liquid phase. These catalysts are based on titanium, and the important discovery was a way to isolate titanium in framework locations of the inner cavities of zeolites (molecular sieves). Thus, mild oxidations may be run in water or water-soluble solvents. Practicing organic chemists now have a way to catalytically oxidize benzene to phenols alkanes to alcohols and ketones primary alcohols to aldehydes, acids, esters, and acetals secondary alcohols to ketones primary amines to oximes secondary amines to hydroxyl-amines and tertiary amines to amine oxides. 

Zeolite based ceramics as catalysts for wet hydrogen peroxide catalytic oxidation of phenol and poly-phenols... 

M. Iwamoto, K. Matsukami, and S. Kagawa, Catalytic oxidation by oxide radical ions. 1. One-step hydroxylation of benzene to phenol over group 5 or 6 oxides supported on silica gel, J. Phys. Chem. 87,903 (1983). 

It is important to emphasize that the atomic oxygen anion-radical plays a role in catalytic oxidation occnrring on varions oxide surfaces. For instance, O reacts with methane at room temperatnre over varions metal oxides (Lee and Gralowsky 1992). On solid catalysis, Q- is more reactive toward alkanes and alkenes than other ionic oxygen species. Iwamoto and Lnnsford (1980) assumed that O is the active oxygen species oxidizing benzene to phenol on with 70% selectivity at... 

Bo, L. and Quan, X. and Wang, X. and Chen, S. (2008). Preparation and characteristics of carbon-supported platinum catalyst and its application in the removal of phenolic pollutants in aqueous solution by microwave-assisted catalytic oxidation. 

The catalytic oxidation of liquid hydrocarbons with air or oxygen. Since oxygen is not very soluble in the liquid, while the hydrocarbon could well be present in high concentration we could end up in extreme 1 (excess of B). The removal of dissolved organics from industrial waste water by catalytic oxidation as an alternative to biooxidation. Here oxygen is not very soluble in water, but the organic waste is also present in low concentration. It is therefore not clear in what regime the kinetics lie. The catalytic oxidation of phenol is an example of such an operation. 

For example, the most noteworthy disadvantage of catalytic wet oxidation is the severe catalyst deactivation (Larachi el al., 1999). Hamoudi el al. (1998, 1999) systematically studied the deactivation of Mn02/Ce02 catalyst during wet catalytic oxidation of phenol and the catalyst-surface modifications. It was observed that deactivation was induced mainly by the formation of carbonaceous deposits on the catalyst surface. Ohta et al. (1980) reported that the size of the catalyst particles affected the stabilization of catalytic activity. For granular particles of supported copper oxide, the catalytic activity was decreased after each inn, even after six successive experiments. In contrast, for larger particles the catalytic activity was stabilized after the first three runs. 

Alkylation. Friedel-Crafts alkylation (qv) of benzene with ethylene or propylene to produce ethylbenzene [100-41 -4], CgH10, or isopropylbenzene [98-82-8], C9H12 (cumene) is readily accomplished in the liquid or vapor phase with various catalysts such as BF3 (22), aluminum chloride, or supported polyphosphoric acid. The oldest method of alkylation employs the liquid-phase reaction of benzene with anhydrous aluminum chloride and ethylene (23). Ethylbenzene is produced commercially almost entirely for styrene manufacture. Cumene [98-82-8] is catalytically oxidized to cumene hydroperoxide, which is used to manufacture phenol and acetone. Benzene is also alkylated with C1Q—C20 linear alkenes to produce linear alkyl aromatics. Sulfonation of these compounds produces linear alkane sulfonates (LAS) which are used as biodegradable deteigents. 

Catalytic oxidation is the most important technology for the conversion of hydrocarbon feedstocks (olefins, aromatics and alkanes) to a variety of bulk industrial chemicals.1 In general, two types of processes are used heterogeneous, gas phase oxidation and homogeneous liquid phase oxidation. The former tend to involve supported metal or metal oxide catalysts e.g. in tne manufacture of ethylene oxide, acrylonitrile and maleic anhydride whilst the latter generally employ dissolved metal salts, e.g. in the production of terephthalic acid, benzoic acid, acetic acid, phenol and propylene oxide. 

Reactions (7.14)-(7.16) represent the main mechanistic steps not only of the stoichiometric, but also of the steady state catalytic oxidation of benzene to phenol. The involvement of a-oxygen in the catalytic oxidation is most convincingly evidenced by a linear dependence of the reaction rate on the concentration of a-sites [134,135]. 

Reviewed previous SCWO research with model pollutants and demonstrated that phenolic compounds are the model pollutants studied most extensively under SCWO conditions Studied supercritical water oxidation of aqueous waste Explored reaction pathways in SCWO of phenol Studied catalytic oxidation in supercritical water Explored metal oxides as catalysts in SCWO Studied decomposition of municipal sludge by SCWO Investigated the SCWO kinetics, products, and pathways for CH3- and CHO-substituted phenols Determined oxidation rates of common organic compounds in SCWO... 

The largest and oldest chemical intermediate use for methanol is formaldehyde. Over half of the methanol currently consumed in the world goes into formaldehyde production. Formaldehyde is produced by the catalytic oxidation or the oxidative dehydrogenation of methanol The major outlet for formaldehyde is amino and phenolic resins. These resins are in turn used in the manufacture of adhesives for wood products, molding compounds, binders for thermal insulation and foundry resins. Formaldehyde is also consumed in the production of acetal resins, pentaerythritol, neopentyl glycol, trimethylolpropane, methylenediphenyldiisocyanate (MDI), and textile treating resins. 

---