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Ethylene glycol, catalytic oxidation

Ethylene. The catalytic oxidation of ethylene to ethylene oxide based on the invention of Lefort has been practiced commercially on a large scale. Ethylene oxide has become an important organic chemical, being used in the manufacture of ethylene glycol, ethanolamines, fi-phenylethyl alcohol, plastics, plasticizers, resins, insecticides, surface-active agents, solvents, explosives, etc. [Pg.529]

Prominent among copolymers of cyclic ethers are interpolymers of oxiranes with tetrahydro-furan. Thus, ethylene oxide copolymerizes with tetrahydrofuran with the aid of a boron trifluoride-ethylene glycol catalytic system. The resultant copolyether diol contains virtually no unsaturation. [Pg.208]

Although catalytic hydration of ethylene oxide to maximize ethylene glycol production has been studied by a number of companies with numerous materials patented as catalysts, there has been no reported industrial manufacture of ethylene glycol via catalytic ethylene oxide hydrolysis. Studied catalysts include sulfonic acids, carboxyUc acids and salts, cation-exchange resins, acidic zeoHtes, haUdes, anion-exchange resins, metals, metal oxides, and metal salts (21—26). Carbon dioxide as a cocatalyst with many of the same materials has also received extensive study. [Pg.359]

In Europe, where an abundant supply of anthracene has usually been available, the preferred method for the manufacture of anthraquinone has been, and stiU is, the catalytic oxidation of anthracene. The main problem has been that of obtaining anthracene, C H q, practically free of such contaminants as carbazole and phenanthrene. Many processes have been developed for the purification of anthracene. Generally these foUow the scheme of taking the cmde anthracene oil, redistilling, and recrystaUizing it from a variety of solvents, such as pyridine (22). The purest anthracene may be obtained by azeotropic distillation with ethylene glycol (23). [Pg.421]

Catalytic oxidation of ethylene produces ethylene oxide, which is hydrolyzed to ethylene glycol. Ethylene glycol is a monomer for the production of synthetic fibers. Chapter 7 discusses chemicals based on ethylene, and Chapter 12 covers polymers and copolymers of ethylene. [Pg.33]

Ethylene oxide is an important intermediate for ethylene glycol (antifreeze) and for plastics, plasticizers, and many other products [R.A. van Santen and H.P.C.E. Kui-pers, Adv. Catal. 35 (1987) 265]. In Chapter 1 we explained that the replacement of the traditional manufacturing process - which generated 1.5 mole of byproducts per 1 mole of epoxide - by a catalytic route based on silver catalysts is a major success story with respect to clean chemistry (Fig. 9.16). [Pg.370]

Table 14. Catalytic activity and selectivity of the 12g x 80g Au/ X40S preparations and 2g x 500g Au/XC72R (a) and 2g preparations (b) in the ethylene glycol oxidation. Table 14. Catalytic activity and selectivity of the 12g x 80g Au/ X40S preparations and 2g x 500g Au/XC72R (a) and 2g preparations (b) in the ethylene glycol oxidation.
In the case of the esterification of the diacid, the reaction is self-catalyzed as the terephthalic acid acts as its own acid catalyst. The reverse reaction, the formation of TPA and EG from BHET is catalytic with regard to the usual metal oxides used to make PET, but is enhanced by either the presence of hydroxyl groups or protons. In the case of transesterification of dimethyl terephthalate with ethylene glycol, the reaction is catalytic, with a metal oxide needed to bring the reaction rate to commercial potential. The catalysts used to produce BHET are the same as those needed to depolymerize both the polymer to BHET and BHET to its simpler esters. Typically, titanium, manganese and zinc oxides are used for catalysts. [Pg.568]

In SL-PC, a catalyst is supported on a solid matrix in the form of the film of a nonvolatile liquid phase adsorbed on the solid. The catalytic film can be, for example, a molten salt or a molten oxide (e.g., Deacon s catalyst (CUCI2/KCI) used to oxidize HCl with oxygen for the chlorination of ethylene in the synthesis of vinyl chloride. Figure 6.1 V2O5 for the oxidation of sulphurous to sulphuric anhydride). Alternately, it can be a liquid phase (e.g., ethylene glycol, PPh3, butyl benzyl phthalate, etc.) that contains a soluble catalytic species such as a metal complex. [Pg.133]

Ethylene oxide, used for the production of ethylene glycol and PEO, is obtained by the catalytic oxidation of ethylene. Ethylene glycol, used in the production of PET, is produced by the hydrolysis of ethylene oxide. [Pg.533]

In a similar manner, coccinelline (99) and precoccinelline (100) have been synthesized from 2,6-lutidine (351) (336,450). Thus, treatment of the monolithium derivative (153) of 351 with P-bromopropionaldehyde dimethylacetal gave an acetal, which was converted to the keto acetal (412) by treatment with phenyllithium and acetonitrile. Reaction of 412 with ethylene glycol and p-toluenesulfonic acid followed by reduction with sodium-isoamyl alcohol gave the cw-piperidine (413). Hydrolysis of 413 with 5% HCl gave the tricyclic acetal (414) which was transformed to a separable 1 1 mixture of the ketones (415 and 416) by treatment with pyrrolidine-acetic acid. Reaction of ketone 416 with methyllithium followed by dehydration with thionyl chloride afforded the rather unstable olefin (417) which on catalytic hydrogenation over platinum oxide in methanol gave precoccinelline (100). Oxidation of 100 with m-chloroperbenzoic acid yielded coccinelline (99) (Scheme 52) (336,450). [Pg.274]

Ethylene adds hypochlorous acid more readily than it adds either moist chlorine or hydrogen chloride. Bubbled into chlorine water, it is converted completely into ethylene chlorohydrin, and by the hydrolysis of this substance glycol is obtained. Ethylene chlorohydrin is important also because of its reaction with ammonia whereby mono-, di-, and triethanolamine are formed, substances which are used in the arts and are not without interest for the explosives chemist. Ethylene may be oxidized catalytically in the gas phase to ethylene oxide which reacts with water to form glycol and with glycol to form diglycol which also is of interest to the dynamite maker. [Pg.224]

The Au-catalyzed glycerol oxidation was influenced by the kind of support, the size of Au particles and the reaction conditions such as concentration of glycerol, p02 and molar ratio of NaOH to glycerol. As metal oxide supports showed inferior selectivity to glyceric acid compared to carbons, due to successive oxidation and C—C bond cleavage to form di-adds such as tartronic acid and glycolic acid, research has focused on Au NPs supported on carbon, as in the case of ethylene glycol oxidation [182]. Indeed, the catalytic activity was influenced by the kind of carbon support in terms of porous texture [183]. [Pg.114]

Approximately 7 billion pounds of eihylene oxide were produced in the United States in 1997, The 1997 selling price was 0.58 a pound, amounting to a commercial value of 4.0 billion. Over 60% of the ethylene oxide produced is used to make ethylene glycoL The major end uses of ethylene oxide are antifreeze (30%), polyester (30%), surfactants (10%), and solvents (5%), We want to calculate the catalyst weight necessary to achieve 60% conversion when ethylene oxide is to be made by the vapor-phase catalytic oxidation of ethylene with air. [Pg.378]


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See also in sourсe #XX -- [ Pg.194 ]




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