Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Hydrogen production catalyst

By using PHIP-NMR studies, various intermediates such as the previously elusive dihydrides of neutral and cationic hydrogenation catalysts, as well as hydrogenation product/catalyst complexes, have already been detected during the hydrogenation of styrene derivatives using cationic Rh catalysts. Information about the substituent effect on chemical shifts and kinetic constants has been obtained via time-resolved PASADENA NMR spectroscopy (DYPAS). [Pg.355]

SEPARATION AND UTLISATION OF RARE METAL FISSION PRODUCTS IN NUCLEAR FUEL CYCLE AS FOR HYDROGEN PRODUCTION CATALYSTS ... [Pg.355]

Gan L, Groy TL, Tarakeshwar P, Mazinani SKS, Shearer J, Mujica V, Jones AK (2015) A nickel phosphine complex as a fast and efficient hydrogen production catalyst. J Am Chem Soc 137(3) 1109-1115. doi 10.1021/ja509779q... [Pg.269]

AlCl and Hydrogen Chloride Catalyst. Historically, AIQ processes have been used more extensively for the production of ethylbenzene than for the production of cumene. In 1976, Monsanto developed an improved cumene process that uses an AIQ. catalyst, and by the mid-1980s, the technology had been successfully commercialized. The overall yields of cumene for this process can be as high as 99 wt % based on benzene and 98 wt % based on propylene (60). [Pg.50]

Shift Conversion. Carbon oxides deactivate the ammonia synthesis catalyst and must be removed prior to the synthesis loop. The exothermic water-gas shift reaction (eq. 23) provides a convenient mechanism to maximize hydrogen production while converting CO to the more easily removable CO2. A two-stage adiabatic reactor sequence is normally employed to maximize this conversion. The bulk of the CO is shifted to CO2 in a high... [Pg.348]

A similar but somewhat less ambitious approach is to carry out dehydrogenation of ethylbenzene and oxidation of the hydrogen product alternately in separate reactors containing different catalysts ... [Pg.484]

Reforming Conditions. The main process variables are pressure, 450—3550 kPa (50—500 psig), temperature (470—530°C), space velocity, and the catalyst employed. An excess of hydrogen (2—8 moles per mole of feed) is usually employed. Depending on feed and processing conditions, net hydrogen production is usually in the range of 140—210 m /m feed (800—1200 SCF/bbl). The C —products are recovered and normally used as fuels. [Pg.308]

Hydrogen fluoride Catalyst in some petroleum refining, etching glass, silicate extraction by-product in electrolytic production of aluminum Petroleum, primary metals, aluminum Strong irritant and corrosive action on all body tissue damage to citrus plants, effect on teeth and bones of cattle from eating plants... [Pg.2174]

A solution of resorcinol (11 g) in sodium hydroxide solution (4.8 g of sodium hydroxide in 20 ml of water) is hydrogenated in the presence of 1.1 g of 5 % rhodium on alumina for 16-18 hours at 50 psi initial pressure in a Parr apparatus. The reduction stops after the absorption of 1 equivalent of hydrogen. The catalyst is removed by filtration through celite, and the aqueous solution is carefully acidified with concentrated hydrochloric acid at 0°. The crude product is collected by filtration, dried in air, and recrystallized from benzene to give 1,3-cyclohexanedione, mp 105-107. ... [Pg.40]

The stereoisomers of olefin saturation are often those derived by cis addition of hydrogen to the least hindered side of the molecule (99). But there are many exceptions and complications (97), among which is the difficulty of determining which side of the molecule is the least hindered. Double-bond isomerization frequently occurs, and the hydrogenation product is the resultant of a number of competing reactions. Experimentally, stereochemistry has been found to vary, sometimes to a marked degree, with olefin purity, reaction parameters, solvent, and catalyst 30,100). Generalizing, it is expedient, when unwanted products arise as a result of prior isomerization, to avoid those catalysts and conditions that are known to favor isomerization. [Pg.45]

Of this material 1.0 g is dissolved in 150 ml of warm 95% ethyl alcohol. To the solution is added 1.0 g of 5% palladium on carbon catalyst, and the mixture is hydrogenated at room temperature and atmospheric pressure by bubbling hydrogen into it for 3 hours with stirring. The hydrogenation product is filtered. The solid phase, comprising the catalyst and the desired product, is suspended in ethyl acetate and water and adjusted to pH 2 with hydrochloric acid. The suspension is filtered to remove the catalyst. The aqueous phase is separated from the filtrate, and is evaporated under vacuum to recover the desired product, 7-(D-a-aminophenylacetamido)cephalosporanic acid. [Pg.283]

The product is hydrogenated in 4,000 cc of ethanol at room temperature and under normal atmospheric pressure with a catalyst prepared In the usual manner from 400 g of Raney nickel alloy. The calculated amount of hydrogen is taken up in approximately 75 hours. After filtration and evaporation to a small volume, the residue Is distributed between 1,000 cc of chloroform and water each. The chloroform solution is then dried over sodium sulfate and evaporated to a small volume. Precipitation of the hydrogenation product with petroleum ether yields an amorphous white powder which Is filtered by suction, washed with petroleum ether and dried at 50°C In a high vacuum. 1. athyl-2-podophyllinic acid hydrazide is obtained in a practically quantitative yield. [Pg.1034]

Both reactions were carried out under two-phase conditions with the help of an additional organic solvent (such as iPrOH). The catalyst could be reused with the same activity and enantioselectivity after decantation of the hydrogenation products. A more recent example, again by de Souza and Dupont, has been reported. They made a detailed study of the asymmetric hydrogenation of a-acetamidocin-namic acid and the kinetic resolution of methyl ( )-3-hydroxy-2-methylenebu-tanoate with chiral Rh(I) and Ru(II) complexes in [BMIM][BF4] and [BMIM][PFg] [55]. The authors described the remarkable effects of the molecular hydrogen concentration in the ionic catalyst layer on the conversion and enantioselectivity of these reactions. The solubility of hydrogen in [BMIM][BF4] was found to be almost four times higher than in [BMIM][PFg]. [Pg.231]

The metals in the FCC feed have many deleterious effects. Nickel causes excess hydrogen production, forcing eventual loss in the conversion or thruput. Both vanadium and sodium destroy catalyst structure, causing losses in activity and selectivity. Solving the undesirable effects of metal poisoning involves several approaches ... [Pg.68]

These metals, when deposited on the E-cat catalyst, increase coke and gas-making tendencies of the catalyst. They cause dehydrogenation reactions, which increase hydrogen production and decrease gasoline yields. Vanadium can also destroy the zeolite activity and thus lead to lower conversion. The deleterious effects of these metals also depend on the regenerator temperature the rate of deactivation of a metal-laden catalyst increases as the regenerator temperature increases. [Pg.108]

Pentapyrrolic macrocycles, 2,888 2,1,2-Pen tathiadiazol e-4,7-dicarbonitrile in hydrogen production from water, 6, 508 Pentatungstobis(organophosphonates), 3, 1053 4-Penten-l-al reaction with ethylene catalysts, rhodium complexes, 6, 300... [Pg.191]


See other pages where Hydrogen production catalyst is mentioned: [Pg.177]    [Pg.205]    [Pg.233]    [Pg.244]    [Pg.248]    [Pg.252]    [Pg.47]    [Pg.91]    [Pg.177]    [Pg.205]    [Pg.233]    [Pg.244]    [Pg.248]    [Pg.252]    [Pg.47]    [Pg.91]    [Pg.371]    [Pg.134]    [Pg.164]    [Pg.419]    [Pg.427]    [Pg.388]    [Pg.402]    [Pg.134]    [Pg.50]    [Pg.333]    [Pg.441]    [Pg.2373]    [Pg.2378]    [Pg.602]    [Pg.237]    [Pg.532]    [Pg.746]    [Pg.23]    [Pg.149]    [Pg.604]    [Pg.559]    [Pg.561]    [Pg.565]    [Pg.106]    [Pg.108]    [Pg.221]   
See also in sourсe #XX -- [ Pg.409 ]




SEARCH



Anthraquinone as a catalyst in the production of hydrogen peroxide

Case - Use of Carbon Nanotube-Based Catalysts in Hydrogen Production

Catalyst poisoning hydrogen production

Catalyst productivity

Catalyst, alumina hydrogenation, Universal Oil Products

Catalysts production

Clay minerals catalysts, hydrogen production from water

Hydrogenation catalysts food production

Titanium oxide catalysts, hydrogen production from water

Zeolites catalysts, hydrogen production from water

© 2024 chempedia.info