Petroleum catechol

Phenolic wastes are one of the most prevalent forms of chemical pollutants in industry today. The major sources of phenolic waste are insulation fiberglass manufacturing, petroleum refineries, textile mills, steel making, plywood, hardboard production, manufacture of organic chemicals, paint stripping, and wood preservatives. Eisenhauer (1964) first studied oxidation of phenolic wastes with Fenton s reagent. It has been demonstrated that the oxidation of phenol involves the intermediate formation of catechol and hydroquinone (Merz and Waters, 1949 Stein and Weiss, 1951 Wieland and... 

Racemic 2,3-butanediol was converted to the racemic ditosy-late, which was then treated with catechol under the influence of NaOH in dimethylformamide (DMF) to yield the desired compounds, cis- and trans-2,3-dimethyl-l,4-benzodioxane [3] and [4]. The solid trans isomer [4] was obtained by repeated recrystallization from methanol. Column chromatography of the mother liquid using AloOj as adsorbent and petroleum ether and diethyl ether in a 1 1 ratio as eluent, gave pure liquid cis isomer [3]. By comparison with the PMR spectra (8) of pure trans- and cis-2,3-dimethyldi-oxane, the solid isomer was identified as trans, and the liquid isomer as cis. The compounds were further characterized by IR, NMR, CMR and elemental analyses. The CMR spectral data for 2 and 4 are summarized in Table I. 

The sap from Rhus vemicifera by extraction with light petroleum affords urushiol a mixture which is considerably more sensitive to oxidative deterioration and polymerisation than the cashew phenols since it is both a catechol and even more highly unsaturated. The composition of the sap is to some extent dependent on the source but typically it contains urushiol (55-65%), water (20-30%), glycoprotein (2-3%), polysaccharides (5-7%) and laccase (-c 1%) (ref. 196 ). 

Genetically engineered microbes have been used by Draths and Frost (1998a, b) to synthesize common but important chemicals such as adipic acid and catechol (see Fig. 3.23). The noteworthy aspect of this work is that the starting materials were renewable feedstock. The principles of green chemistry state that "a raw material of feedstock should be renewable rather than depleting wherever technically and economically practicable" (Anastas and Warner, 1998). This reaction addresses this principle and more, as it can be seen. Classical catechol synthesis beginning with benzene (obtained from petroleum, a nonrenewable feedstock) involves a multistep process (see Fig. 3.22). 

Chemical intermediates, such as catechol and adipic acid, used in the manufacture of nylon-6,6, polyurethane, lubricants, and plasticizers are normally derived from petroleum-based benzene and toluene. Airborne benzene causes cancer and leukemia toluene leads to brain, liver, and kidney damage, and debilitates capacity for speech, vision, and balance. Researchers at Michigan State have developed a green method for biosynthesizing catechol and adipic acid from glucose, rather than from benzene and toluene, using genetically altered E. coli ... 

Another common theme is seen in the transformation of the commercially important BTEX compounds (i.e., benzene, toluene, ethylbenzene, and xylenes). They are clustered because of their co-occurrence in environmental contamination stemming from spillage of petroleum materials. Because BTEX compounds are structurally analogous to each other, there are commonalities in their metabolism by prokaryotes. Anaerobic metabolism of BTEX compounds has been studied only more recently, and the biochemical basis of the biodegradation reactions is now being revealed. The aerobic metabolism of BTEX compounds is much better studied. For example, see O Fig. 15.3 and (http //umbbd.ahc.umn.edu/ BTEX/BTEX map.html aerobic). Almost invariably, oxygenase enzymes initiate the metabolism to produce ring cis-dihydrodiols, phenols, benzyl alcohols, and ultimately catechols. 

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