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Treating processes phenol

Caustics are widely used in petroleum refineries. Typical uses are to neutralize and to extract acidic materials that may occur naturally in crude oil, acidic reaction products that may be produced by various chemical treating processes, and acidic materials formed during thermal and catalytic cracking such as H2S, phenolics, and organic acids. [Pg.279]

Early Synthesis. Reported by Kolbe in 1859, the synthetic route for preparing the acid was by treating phenol with carbon dioxide in the presence of metallic sodium (6). During this early period, the only practical route for large quantities of sahcyhc acid was the saponification of methyl sahcylate obtained from the leaves of wintergreen or the bark of sweet bitch. The first suitable commercial synthetic process was introduced by Kolbe 15 years later in 1874 and is the route most commonly used in the 1990s. In this process, dry sodium phenate reacts with carbon dioxide under pressure at elevated (180—200°C) temperature (7). There were limitations, however not only was the reaction reversible, but the best possible yield of sahcyhc acid was 50%. An improvement by Schmitt was the control of temperature, and the separation of the reaction into two parts. At lower (120—140°C) temperatures and under pressures of 500—700 kPa (5—7 atm), the absorption of carbon dioxide forms the intermediate phenyl carbonate almost quantitatively (8,9). The sodium phenyl carbonate rearranges predominately to the ortho-isomer. sodium sahcylate (eq. 8). [Pg.286]

Ozone can be used to completely oxidize low concentrations of organics in aqueous streams or partially degrade compounds that are refractory or difficult to treat by other methods. Compounds that can be treated with ozone include alkanes, alcohols, ketones, aldehydes, phenols, benzene and its derivatives, and cyanide. Ozone readHy oxidizes cyanide to cyanate, however, further oxidation of the cyanate by ozone proceeds rather slowly and may require other oxidation treatment like alkaline chlorination to complete the degradation process. [Pg.163]

Wastewater Treating. Earlier we discussed the importance of bringing environmental experts into the project early. Wastew ater treating can be part of the battery limits process area in the case of phenol extraction from coal gasification gas liquor, but this is an e.xception. [Pg.229]

In the sulphonation process vaporised benzene is forced through a mist of sulphuric acid at 100-120°C and the benzene sulphonic acid formed is neutralised with soda ash to produce benzene sodium sulphonate. This is fused with a 25-30% excess of caustic soda at 300-400°C. The sodium phenate obtained is treated with sulphuric acid and the phenol produced is distilled with steam (Figure 23.1). [Pg.636]

The raw material has to be washed to remove impurities. Diluted sodium hydroxide allows the removal of phenols and benzonitrile, and diluted sulphuric acid reacts with pyridine bases. The resulting material is distilled to concentrate the unsaturated compounds (raw feedstock for coumarone-indene resin production), and separate and recover interesting non-polymerizable compounds (naphthalene, benzene, toluene, xylenes). Once the unsaturated compounds are distilled, they are treated with small amounts of sulphuric acid to improve their colour activated carbons or clays can be also used. The resulting material is subjected to polymerization. It is important to avoid long storage time of the feedstock because oxidation processes can easily occur, affecting the polymerization reaction and the colour of the coumarone-indene resins. [Pg.604]

The process for preparing the enzyme composition comprises treating an aqueous solution of the snake venom at a pH of about 4 to 6 with phenol or a phenol derivative in order to precipitate an insoluble complex containing the active venom fraction and decomposing the complex in order to release the thrombinlike enzyme composition. [Pg.129]

To support a polystyrene onto the upper rim of ca-lix[4]arene (phenolic-O- of calix[4]arene) and 25,26,27-tribenzoyloxy-28-hydroxy, calix[4]arene was treated with chloromethylated polystyrene in the presence of K2CO3 (Scheme 7). Polymeric calix[4]arene (3a) thus obtained was hydrolyzed in the benzoyl groups prior to use for the extraction process. [Pg.345]

The simultaneous reaction of sulfur dioxide and chlorine with paraffins, named sulfochlorination, was discovered by Reed and Horn in the 1930s [9]. The primary products of this reaction are the alkanesulfochlorides [10], which can be saponified to alkanesulfonates by sodium hydroxide solution or treated with substituted phenolates to give plasticisers. In a short time the process was industrially realized to secure detergent production during World War II in Germany [11]. [Pg.154]

The reaction of alkyl sulfates with alkoxide ions is quite similar to 10-12 in mechanism and scope. Other inorganic esters can also be used. One of the most common usages of the reaction is the formation of methyl ethers of alcohols and phenols by treatment of alkoxides or aroxides with methyl sulfate. The alcohol or phenol can be methylated directly, by treatment with dimethyl sulfate and alumina in cyclohexane. Carboxylic esters sometimes give ethers when treated with alkoxides (Bal2 mechanism, p. 473) in a very similar process (see also 10-24). [Pg.478]

One common application of liquid-liquid extraction is the removal and recovery of phenol and compounds of phenol from wastewaters. Although phenol can be removed by biological treatment, only limited levels can be treated biologically. Variations in phenol concentration are also a problem with biological treatment, since the biological processes take time to adjust to the variations. [Pg.587]

Lurascu B, Siminiceanu I, Vione D, Vicente MA, Gil A (2009) Phenol degradation in water through a heterogeneous photo-Fenton process catalyzed by Fe-treated laponite. Water Res 43 1313-1322... [Pg.308]

Since phenol forms the hydrogen bond with any O-containing compound, it can form hydrogen bond with the peroxyl radical too [48] and hence the reaction of the peroxyl radical with phenol should be treated as a two-stage process ... [Pg.520]

The Phenosolvan process is used in the treatment of wastewaters from plants involving phenol synthesis, coke ovens, coal gasification, low-pressure carbonization, and plastic manufacturing. The residual phenol content after dephenolization is usually in the range 5-20 mg dm and plants treating 500 m water per day are in operation. [Pg.438]


See other pages where Treating processes phenol is mentioned: [Pg.3]    [Pg.12]    [Pg.359]    [Pg.4]    [Pg.2792]    [Pg.2792]    [Pg.313]    [Pg.502]    [Pg.342]    [Pg.163]    [Pg.304]    [Pg.565]    [Pg.112]    [Pg.470]    [Pg.729]    [Pg.945]    [Pg.420]    [Pg.287]    [Pg.3]    [Pg.189]    [Pg.133]    [Pg.442]    [Pg.155]    [Pg.967]    [Pg.172]    [Pg.109]    [Pg.122]    [Pg.144]    [Pg.151]    [Pg.93]    [Pg.316]    [Pg.61]    [Pg.326]    [Pg.56]    [Pg.183]   
See also in sourсe #XX -- [ Pg.87 , Pg.348 , Pg.351 , Pg.362 , Pg.365 , Pg.365 , Pg.608 , Pg.608 , Pg.874 , Pg.874 , Pg.878 ]




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