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Ethylene-phosphoric acid

Sodium hypochlorite Ethylene Phosphoric acid Sodium hydroxide 20% and above... [Pg.408]

Detergents may be produced by the chemical reaction of fats and fatty acids with polar materials such as sulfuric or phosphoric acid or ethylene oxide. Detergents emulsify oil and grease because of their abiUty to reduce the surface tension and contact angle of water as well as the interfacial tension between water and oil. Recent trends in detergents have been to lower phosphate content to prevent eutrification of lakes when detergents are disposed of in municipal waste. [Pg.135]

Anodic Oxidation. The abiUty of tantalum to support a stable, insulating anodic oxide film accounts for the majority of tantalum powder usage (see Thin films). The film is produced or formed by making the metal, usually as a sintered porous pellet, the anode in an electrochemical cell. The electrolyte is most often a dilute aqueous solution of phosphoric acid, although high voltage appHcations often require substitution of some of the water with more aprotic solvents like ethylene glycol or Carbowax (49). The electrolyte temperature is between 60 and 90°C. [Pg.331]

Chemistry. The stoichiometric equations pertinent to the vapor-phase hydration of ethylene over a catalyst support impregnated with phosphoric acid have been summari2ed (84). [Pg.404]

The kinetics of the ethylene hydration reaction have been investigated for a tungstic oxide—siHca gel catalyst, and the energy of activation for the reaction deterrnined to be 125 kJ/mol (- 30 kcal/mol) (106,120). The kinetics over a phosphoric acid-siHca gel catalyst have been examined (121). By making some simplifying assumptions to Taft s mechanism, a rate equation was derived ... [Pg.405]

Hydration of Ethyl Ether. Using the same type of acid catalysts as in the hydration of ethylene to ethanol, ethyl ether can be hydrated to the alcohol. Catalysts that have been used for the hydration of ether include phosphoric acid (144), sulfuric acid (145,146), hydrochloric acid (147), metallic oxides (141,148,149) and sihcates (150). Sulfuric acid concentrations ranging from 5—25% at 200°C (144) to 63—70% at 110—135°C and 1.01—1.42 MPa (10—14 atm) (148) have been claimed. [Pg.407]

Manufacture. Much of the diethyl ether manufactured is obtained as a by-product when ethanol (qv) is produced by the vapor-phase hydration of ethylene (qv) over a supported phosphoric acid catalyst. Such a process has the flexibiHty to adjust to some extent the relative amounts of ethanol and diethyl ether produced in order to meet existing market demands. Diethyl ether can be prepared directly to greater than 95% yield by the vapor-phase dehydration of ethanol in a fixed-bed reactor using an alumina catalyst (21). [Pg.427]

Activated alumina and phosphoric acid on a suitable support have become the choices for an iadustrial process. Ziac oxide with alumina has also been claimed to be a good catalyst. The actual mechanism of dehydration is not known. In iadustrial production, the ethylene yield is 94 to 99% of the theoretical value depending on the processiag scheme. Traces of aldehyde, acids, higher hydrocarbons, and carbon oxides, as well as water, have to be removed. Fixed-bed processes developed at the beginning of this century have been commercialized in many countries, and small-scale industries are still in operation in Brazil and India. New fluid-bed processes have been developed to reduce the plant investment and operating costs (102,103). Commercially available processes include the Lummus processes (fixed and fluidized-bed processes), Halcon/Scientific Design process, NIKK/JGC process, and the Petrobras process. In all these processes, typical ethylene yield is between 94 and 99%. [Pg.444]

Isomerization of ethylene oxide to acetaldehyde occurs at elevated temperatures ia the presence of catalysts such as activated alumina, phosphoric acid, and metallic phosphates (75). Iron oxides also catalyze this reaction. Acetaldehyde may be found as a trace impurity ia ethylene oxide. [Pg.454]

N,N-bis(/3-chloroethyl)phosphoric acid amide dichloride Ethylene chlorohydrin 1,3-Propanolamine... [Pg.434]

The hydration reaction is carried out in a reactor at approximately 300°C and 70 atmospheres. The reaction is favored at relatively lower temperatures and higher pressures. Phosphoric acid on diatomaceous earth is the catalyst. To avoid catalyst losses, a water/ethylene mole ratio less than one is used. Conversion of ethylene is limited to 4-5% under these conditions, and unreacted ethylene is recycled. A high selectivity to ethanol is obtained (95-97%). [Pg.205]

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]

Monoester salts of phosphoric acid derived from fatty alcohol ethylene oxide adduct or alkylphenol ethylene oxide adduct useful as surfactants are prepared by addition of R(OCH2CH2) OH, alkali fluoride and (C12P0)20 in a molar ratio of 0.9-1.5 0.05-1 1.0 at -50 to + 10°C and hydrolysis of the Cl-containing intermediates with a base. The monoester phosphates showed comparable or better washing and foaming efficiency than commercial products [12]. [Pg.562]

Whereas nonionic ethylene oxide adducts discolor badly on contact with sodium hydroxide, phosphate derivatives of these nonionics exhibit good color stability even under these conditions. But in the presence of strong acids poly-oxyethylated phosphate esters undergo hydrolysis to the base nonionic and phosphoric acid. However, the free surface-active acids by themselves show little tendency to hydrolyze. They have a pH value of 2 in aqueous solution. [Pg.564]

On the other hand, phosphorous acid monoesters of lower alcohols easily undergo transesterification [75]. A preferred starting material is the triester of ethylene chlorohydrin, obtained by reaction of phosphorus trichloride with ethylene oxide, according to Eq. (28). [Pg.567]

The solubility of phosphoric acid esters in water and organic solvents is controlled by the chain length of the alkyl groups and the ethylene oxide con-... [Pg.590]

Phosphoric acid esters are strong acids similar to orthophosphoric acid. Potentiometric titration of a 0.1 N aqueous solution of an acid phosphoric acid ester clearly shows two potential jumps which lie at pH values of 6.5 and 11.5. The pH value of diluted aqueous solutions of acid esters lies in the range of 1-3. Phosphoric acid esters are stable against hydrolysis, but adducts of free phosphoric acid esters with ethylene oxide are generally less stable. [Pg.591]

For a number of reactions of cyclic di- and triesters of phosphoric acid, there are exchange data which can be rationalized on the assumption of trigonal bipyrami-dal intermediates which readily interconvert by pseudorotation. This constitutes a strong argument that at least these cyclic esters react by an associative mechanism and is suggestive evidence that simple trialkyl phosphates also react by this mechanism. The pH dependence of exocyclic versus endocyclic cleavage of methyl ethylene phosphate is readily interpreted in terms of the effect of ionization of the intermediate on the pseudorotation of these pentacoordinate intermediates. ... [Pg.22]

Environmental inflows/outflows, in life cycle assessment, 74 809-810 Environmental interactions, test temperature and, 73 487-488 Environmental interventions, in life cycle assessment, 74 820 Environmental issues. See also Environmental concerns concerning phosphoric acids and phosphates, 73 861 electric furnaces, 72 314 emulsion-related, 70 128 ethylene glycol, 72 653-655 with fermentation, 77 49 in fine art examination/conservation, 77 407 108... [Pg.320]

This is a general reaction. Thus ethylene oxide with phosphoric acid gives partial or complete esterification. Phosphorous acid, even when completely esterified, gives only the di-ester 1... [Pg.112]

If the ethylene produced with sulphuric acid is analysed (method ) it is found that very much carbon monoxide is present. The phosphoric acid method is better suited for the production of the pure gas, but the best way is to remove with zinc dust and glacial acetic acid the bromine from the ethylene dibromide already prepared. The dibromide is dropped into a suspension of an excess (not too great) of zinc dust in alcohol and glacial acetic acid (2-5 moles) and the ethylene is collected over water in a gas-holder. [Pg.109]

Ethylene is compressed to 1000 psi, mixed with water, and heated to 600°E The two reactants, both. in, a vapor phase, are fed down a catalyst-filled reactor. The catalyst is phosphoric acid (H3PO4) absorbed onto a porous inert support (usually diatomaceous earth or silica gel). [Pg.195]

The reachon of benzene with ethylene or propylene to form ethylbenzene or isopropylbenzene (cumene) is an industrially important transformahon, with ethylbenzene as the key building block for polystyrene and cumene as the feedstock for phenol produchon [55]. Fthylbenzene was originally produced with a Lewis acid catalyst consishng of AlCfi or a Bronsted acidic solid phosphoric acid (SPA) catalyst [56]. Both catalyst systems suffered from equipment corrosion so, in the 1980s the Mobil-Badger vapor phase alkylation process was introduced, which... [Pg.364]

CASRN 16672-87-0 molecular formula C2H6CIO3P FW 144.50 Soil Degrades rapidly in soil to phosphoric acid, ethylene, and chloride ions (Hartley and Kidd, 1987) and naturally occurring substances (Hamburg et ah, 1989). [Pg.1581]

Note that ethylbenzene is a derivative of two basic organic chemicals, ethylene and benzene. A vapor-phase method with boron trifluoride, phosphoric acid, or alumina-silica as catalysts has given away to a liquid-phase reaction with aluminum chloride at 90°C and atmospheric pressure. A new Mobil-Badger zeolite catalyst at 420°C and 175-300 psi in the gas phase may be the method of choice for future plants to avoid corrosion problems. The mechanism of the reaction involves complexation of the... [Pg.154]

Synthetic ethanol is made by the hydration of ethylene over a phosphoric acid-on-celite catalyst and accounts for 8% of all ethanol. [Pg.229]

Phosphoric acid may be used for the polymerization of all the gaseous olefins. Ethylene is converted to ethyl phosphoric acid at temperatures below 250°. At higher temperatures, the ester decomposes to yield conjunct polymer including isobutane. Propylene Undergoes either conjunct or true polymerization depending on whether the reaction temperature is above or below 300°. The butylenes undergo true polymerization chiefly. [Pg.23]


See other pages where Ethylene-phosphoric acid is mentioned: [Pg.7]    [Pg.7]    [Pg.165]    [Pg.321]    [Pg.481]    [Pg.130]    [Pg.405]    [Pg.272]    [Pg.591]    [Pg.434]    [Pg.1556]    [Pg.289]    [Pg.559]    [Pg.578]    [Pg.603]    [Pg.605]    [Pg.610]    [Pg.1596]    [Pg.71]    [Pg.77]    [Pg.109]    [Pg.396]   
See also in sourсe #XX -- [ Pg.7 ]




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