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And propylene oxide

Alkanolamines with at least one NCH2CHOHCH,i grouping. Important materials include monoisopropanolamine NHX H CHOHCH, b.p. 159 C di-iso-propanolamine NH(CH CHOHCH b.p. 248 C triisopropanolamine NtCH -CHOHCHi). , b.p. 300 C. Manufactured from ammonia and propylene oxide. U ed, is weedkillers, as stabilizers for plastics, in detergents, alkanolaniine soaps for sweetening natural gas and in synthesis. [Pg.227]

DIblook oopolymers of ethylene oxide and propylene oxide... [Pg.2579]

Three membered rings that contain oxygen are called epoxides At one time epox ides were named as oxides of alkenes Ethylene oxide and propylene oxide for exam pie are the common names of two industrially important epoxides... [Pg.260]

Substitutive lUPAC nomenclature names epoxides as epoxy derivatives of alkanes According to this system ethylene oxide becomes epoxyethane and propylene oxide becomes 1 2 epoxypropane The prefix epoxy always immediately precedes the alkane ending it is not listed m alphabetical order like other substituents... [Pg.260]

PROPENE The major use of propene is in the produc tion of polypropylene Two other propene derived organic chemicals acrylonitrile and propylene oxide are also starting materials for polymer synthesis Acrylonitrile is used to make acrylic fibers (see Table 6 5) and propylene oxide is one component in the preparation of polyurethane polymers Cumene itself has no direct uses but rather serves as the starting material in a process that yields two valuable indus trial chemicals acetone and phenol... [Pg.269]

Acrolein is produced according to the specifications in Table 3. Acetaldehyde and acetone are the principal carbonyl impurities in freshly distilled acrolein. Acrolein dimer accumulates at 0.50% in 30 days at 25°C. Analysis by two gas chromatographic methods with thermal conductivity detectors can determine all significant impurities in acrolein. The analysis with Porapak Q, 175—300 p.m (50—80 mesh), programmed from 60 to 250°C at 10°C/min, does not separate acetone, propionaldehyde, and propylene oxide from acrolein. These separations are made with 20% Tergitol E-35 on 250—350 p.m (45—60 mesh) Chromosorb W, kept at 40°C until acrolein elutes and then programmed rapidly to 190°C to elute the remaining components. [Pg.124]

Diester/Ether Diol of Tetrabromophthalic Anhydride. This material [77098-07-8] is prepared from TBPA in a two-step reaction. First TBPA reacts with diethylene glycol to produce an acid ester. The acid ester and propylene oxide then react to give a diester. The final product, a triol having two primary and one secondary hydroxyl group, is used exclusively as a flame retardant for rigid polyurethane foam (53,54). [Pg.470]

In this process, the fine powder of lithium phosphate used as catalyst is dispersed, and propylene oxide is fed at 300°C to the reactor, and the product, ahyl alcohol, together with unreacted propylene oxide is removed by distihation (25). By-products such as acetone and propionaldehyde, which are isomers of propylene oxide, are formed, but the conversion of propylene oxide is 40% and the selectivity to ahyl alcohol reaches more than 90% (25). However, ahyl alcohol obtained by this process contains approximately 0.6% of propanol. Until 1984, ah ahyl alcohol manufacturers were using this process. Since 1985 Showa Denko K.K. has produced ahyl alcohol industriahy by a new process which they developed (6,7). This process, which was developed partiy for the purpose of producing epichlorohydrin via ahyl alcohol as the intermediate, has the potential to be the main process for production of ahyl alcohol. The reaction scheme is as fohows ... [Pg.74]

Similarly, carbon disulfide and propylene oxide reactions are cataly2ed by magnesium oxide to yield episulftdes (54), and by derivatives of diethyUiac to yield low molecular weight copolymers (55). Use of tertiary amines as catalysts under pressure produces propylene trithiocarbonate (56). [Pg.135]

Hydrogen Sulfide andMercaptans. Hydrogen sulfide and propylene oxide react to produce l-mercapto-2-propanol and bis(2-hydroxypropyl) sulfide (69,70). Reaction of the epoxide with mercaptans yields 1-aLkylthio- or l-arylthio-2-propanol when basic catalysis is used (71). Acid catalysts produce a mixture of primary and secondary hydroxy products, but ia low yield (72). Suitable catalysts iaclude sodium hydroxide, sodium salts of the mercaptan, tetraaLkylammonium hydroxide, acidic 2eohtes, and sodium salts of an alkoxylated alcohol or mercaptan (26,69,70,73,74). [Pg.135]

Friedel-Crafts. 2-Phenylpropanol results from the catalytic (AlCl, FeCl, or TiCl reaction of ben2ene and propylene oxide at low temperature and under anhydrous conditions (see Friedel-CRAFTS reactions). Epoxide reaction with toluene gives a mixture of 0-, m- and -isomers (75,76). [Pg.135]

Trimethyl aluminum and propylene oxide form a mixture of 2-methyl-1-propanol and 2-butanol (105). Triethyl aluminum yields products of 2-methyl-1-butanol and 2-pentanol (106). The ratio of products is determined by the ratio of reactants. Hydrolysis of the products of methyl aluminum dichloride and propylene oxide results ia 2-methylpropeae and 2-butene, with elimination of methane (105). Numerous other nucleophilic (107) and electrophilic (108) reactions of propylene oxide have been described ia the Hterature. [Pg.135]

Methyl formate and propylene oxide have close boiling poiats, making separation by distillation difficult. Methyl formate is removed from propylene oxide by hydrolysis with an aqueous base and glycerol, followed by phase separation and distillation (152,153). Methyl formate may be hydrolyzed to methanol and formic acid by contacting the propylene oxide stream with a basic ion-exchange resia. Methanol and formic acid are removed by extractive distillation (154). [Pg.139]

Styrene manufacture by dehydrogenation of ethylbenzene is simple ia concept and has the virtue of beiag a siagle-product technology, an important consideration for a product of such enormous volume. This route is used for nearly 90% of the worldwide styrene production. The rest is obtained from the coproduction of propylene oxide (PO) and styrene (SM). The PO—SM route is complex and capital-iatensive ia comparison to dehydrogenation of ethylbenzene, but it stiU can be very attractive. However, its use is limited by the mismatch between the demands for styrene and propylene oxides (qv). [Pg.481]

PO—SM Coproduction. The copioduction of propylene oxide and styrene (40—49) includes three reaction steps (/) oxidation of ethylbenzene to ethylbenzene hydroperoxide, (2) epoxidation of ethylbenzene hydroperoxide with propylene to form a-phenylethanol and propylene oxide, and (3) dehydration of a-phenylethanol to styrene. [Pg.484]

The oxidation step is similar to the oxidation of cumene to cumene hydroperoxide that was developed earlier and is widely used in the production of phenol and acetone. It is carried out with air bubbling through the Hquid reaction mixture in a series of reactors with decreasing temperatures from 150 to 130°C, approximately. The epoxidation of ethylbenzene hydroperoxide to a-phenylethanol and propylene oxide is the key development in the process. [Pg.484]

Polyurethane foams are formed by reaction with glycerol with poly(propylene oxide), sometimes capped with poly(ethylene oxide) groups with a reaction product of trimethylolpropane and propylene oxide or with other appropriate polyols. A typical reaction sequence is shown below, in which HO—R—OH represents the diol. If a triol is used, a cross-linked product is obtained. [Pg.190]

The glycol ethers obtained from /-butyl alcohol and propylene oxide, eg, l-/-butoxy-2-propanol, have lower toxicities than the widely employed 2-butoxyethanol and are used in industrial coatings and to solubiHze organic components in aqueous formulations (28). [Pg.358]

Dehydrochlorination to Epoxides. The most useful chemical reaction of chlorohydrins is dehydrochlotination to form epoxides (oxkanes). This reaction was first described by Wurtz in 1859 (12) in which ethylene chlorohydria and propylene chlorohydria were treated with aqueous potassium hydroxide [1310-58-3] to form ethylene oxide and propylene oxide, respectively. For many years both of these epoxides were produced industrially by the dehydrochlotination reaction. In the past 40 years, the ethylene oxide process based on chlorohydria has been replaced by the dkect oxidation of ethylene over silver catalysts. However, such epoxides as propylene oxide (qv) and epichl orohydrin are stiU manufactured by processes that involve chlorohydria intermediates. [Pg.72]

There have been a number of cell designs tested for this reaction. Undivided cells using sodium bromide electrolyte have been tried (see, for example. Ref. 29). These have had electrode shapes for in-ceU propylene absorption into the electrolyte. The chief advantages of the electrochemical route to propylene oxide are elimination of the need for chlorine and lime, as well as avoidance of calcium chloride disposal (see Calcium compounds, calcium CHLORIDE Lime and limestone). An indirect electrochemical approach meeting these same objectives employs the chlorine produced at the anode of a membrane cell for preparing the propylene chlorohydrin external to the electrolysis system. The caustic made at the cathode is used to convert the chlorohydrin to propylene oxide, reforming a NaCl solution which is recycled. Attractive economics are claimed for this combined chlor-alkali electrolysis and propylene oxide manufacture (135). [Pg.103]

Other Derivatives. Ethylene carbonate, made from the reaction of ethylene oxide and carbon dioxide, is used as a solvent. Acrylonitrile (qv) can be made from ethylene oxide via ethylene cyanohydrin however, this route has been entirely supplanted by more economic processes. Urethane intermediates can be produced using both ethylene oxide and propylene oxide in their stmctures (281) (see Urethane polymers). [Pg.466]

Both ethylene and propylene oxide have been used in the preparation of adducts from a variety of amines, including ethylene diamine and diethylene triamine. The latter amine provides adducts which appetu" free of skin sensitising effects. [Pg.754]

Block copolymers of ethylene oxide and propylene oxide, less hydrophilic than poly(oxyethylene) glycol and more reactive than the propylene oxide polymers, were introduced by Wyandotte Chemical (USA) under the trade name Pluronic. [Pg.795]

Development of the technology of ethylene and propylene oxide processing 98MI43. [Pg.243]

Naoi and co-workers [55], with a QCM, studied lithium deposition and dissolution processes in the presence of polymer surfactants in an attempt to obtain the uniform current distribution at the electrode surface and hence smooth surface morphology of the deposited lithium. The polymer surfactants they used were polyethyleneglycol dimethyl ether (molecular weight 446), or a copolymer of dimethylsilicone (ca. 25 wt%) and propylene oxide (ca. 75 wt%) (molecular weight 3000) in LiC104-EC/DMC (3 2, v/v). [Pg.348]

A way to anh-configurated a-amino-/ -hydroxycarboxylic acids is opened by the aldol addition of oxazolidine amides 7a and 7b. The method1061 is illustrated by a synthesis of (2R,3R)-p-hydroxyleucine (9) which is available from the major diastereomeric adduct 8 (d.r. 92 8) upon successive treatment with 1 N HC1 (30 min). 5 N HCl (100 C, 12 h), and propylene oxide (reflux in ethanol, 30 min). [Pg.506]

The alkyl iodides formed in the reaction are used to characterize the alkyl chain by GC. An alternative method is the cleavage with hydrogen bromide and GC of the alkyl bromides. A detailed discussion of the analytical techniques applicable to the analysis of the ethylene and propylene oxide content as well as the alkyl chain distribution has been made by Cross [311]. [Pg.286]

Phosphoric acid esters based on alkylene oxide adducts are of great interest. Their properties can be altered by the length and structure of the hydrophobic alkyl chain. But they are also controlled by the kind and length of the hydrophilic alkyleneoxide chain. The latter can easily be tailored by selection between ethylene oxide and propylene oxide and by the degree of alkoxylation. [Pg.560]

If primary alcohols with a straight chain of 10-20 carbon atoms are initially alkoxylated by a mixture of ethylene and propylene oxides followed by phosphorylation, a pour point depression to 8°C will occur, whereas phosphate esters derived from nonylphenol are liquid at temperatures as low as 2°C. Phosphoric acid esters on the base of linear primary alcohols (Cn-Cl5) generally solidify below 24°C [50] (Table 2). [Pg.561]


See other pages where And propylene oxide is mentioned: [Pg.149]    [Pg.182]    [Pg.304]    [Pg.67]    [Pg.254]    [Pg.341]    [Pg.45]    [Pg.124]    [Pg.798]    [Pg.93]    [Pg.1265]    [Pg.158]    [Pg.342]    [Pg.344]    [Pg.426]    [Pg.85]    [Pg.211]    [Pg.603]   
See also in sourсe #XX -- [ Pg.367 , Pg.368 , Pg.369 ]




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Propylene Oxidation and Ammoxidation

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Selective Oxidation of Propylene George W. Keulks, L. David Krenzke, and Thomas N. Notermann

Styrene and Propylene Oxide (SMPO Process)

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