Liquid-phase catalytic hydrogenation

Hexanediamine can also be obtained by the liquid phase catalytic hydrogenation of adiponitrile or adipamide, which is made from adipic acid. 

The role of complexes and modifiers in the reduction has been discussed in [20-24]. The investigation of the liquid phase catalytic hydrogenation of N03 , N02, and NH2OH at tungsten carbide catalyst furnished interesting information concerning the electrocatalytic properties of the latter [25]. 

Allied-Signal Process. Cyclohexanone [108-94-1] is produced in 98% yield at 95% conversion by liquid-phase catalytic hydrogenation of phenol. Hydroxylamine sulfate is produced in aqueous solution by the conventional Raschig process, wherein NO from the catalytic air oxidation of ammonia is absorbed in ammonium carbonate solution as ammonium nitrite (eq. 1). The latter is reduced with sulfur dioxide to hydroxylamine disulfonate (eq. 2), which is hydrolyzed to acidic hydroxylamine sulfate solution (eq. 3). 

The present work reports on results of the liquid-phase catalytic hydrogenation of butynediol on supported nickel catalysts specifically tailored for these processes. In this respect, we have studied support effects, the influence of nickel loading as well as the influence of Cu as a second metal. 

Application Produce high-purity cyclohexane by liquid-phase catalytic hydrogenation of benzene. 

Mazzarino and Seigi [llj have examined the liquid-phase catalytic hydrogenation of styrene in n-butanol in gas-liquid cocurrent flow, using a Pd-on-Al203 catalyst, and they summarize their findings as follows. 

Derivation (1) Reaction of adipic acid and ammonia (catalytic vapor phase) to yield adiponitrile, followed by liquid-phase catalytic hydrogenation. (2) Chlorination of butadiene followed by reaction with sodium cyanide (cuprous chloride catalyst) to 1,4-dicyanobutylene and hydrogenation. 

Liquid phase catalytic hydrogenation of benzophenone Role of metal support interaction, bimetallic catalysts, solvents and additives... 

Bawane SP, Sawant SB. (2003) Kinetics of liquid-phase catalytic hydrogenation of benzophenone to benzhydrol. Org. Proc. Res. Dev., 7 769-773. 

Bawane SP, Sawant SB. (2004) Liquid phase catalytic hydrogenation of /)-chlorobenzophe-none to /7-chlorobenzhydrol over a 5% Pd/C catalyst. Chem. Eng. TechnoL, 27 914—920. 

Liquid-phase catalytic hydrogenation involves dissolving H2 gas in a solvent such as propane or dimethyl ether at a super critical pressure to achieve a single phase (see Fig. 6.28), thereby reducing the number of resistances (see Fig. 6.29). 

Manufacture. Tetrahydrofurfuryl alcohol is produced commercially by the vapor-phase catalytic hydrogenation of furfuryl alcohol. Liquid phase reduction is also possible. 

Hydrogenation. Gas-phase catalytic hydrogenation of succinic anhydride yields y-butyrolactone [96-48-0] (GBL), tetrahydrofuran [109-99-9] (THF), 1,4-butanediol (BDO), or a mixture of these products, depending on the experimental conditions. Catalysts mentioned in the literature include copper chromites with various additives (72), copper—zinc oxides with promoters (73—75), and mthenium (76). The same products are obtained by liquid-phase hydrogenation catalysts used include Pd with various modifiers on various carriers (77—80), Ru on C (81) or Ru complexes (82,83), Rh on C (79), Cu—Co—Mn oxides (84), Co—Ni—Re oxides (85), Cu—Ti oxides (86), Ca—Mo—Ni on diatomaceous earth (87), and Mo—Ba—Re oxides (88). Chemical reduction of succinic anhydride to GBL or THF can be performed with 2-propanol in the presence of Zr02 catalyst (89,90). 

Liquid phase catalytic oxidation of ethylbenzene with hydrogen peroxide over TS-1 molecular sieves is most appropriate for the production of 1-phenylethanol with high selectivity (up to 93 % of all the oxidation products in methanol) under the reaction conditions studied here. An additional increase of the 1-phenylethanol selectivity could be achieved with smaller amounts of the catalyst. The highest conversion to acetophenone is found over TS-2 zeolites but further oxidation easily takes place in this case. 

Wismeijer et al. studied the liquid phase transfer hydrogenation of 4-tert-butylcyclohexanone by 2-propanol at 83°C over activated y-Al203 as the catalyst [4]. The activity of the catalyst was found to increase with increasing activation temperature. Selective poisoning experiments indicated that coordinatively unsaturated Al " surface ions (Lewis acid sites), formed upon dehydroxylation, were essential for catalytic activity. During reaction the catalyst was found to become conditioned by irreversible alcoholysis of the initial active sites, producing less-active sites. The reaction mechanism, however, remained essentially the same as indicated by the constant ratio of c/s//rans-4-/er/-butylcyclohexanol (9/91). 

Liquid-phase selective hydrogenation of ethyl linolate to ethyl oleate has been carried out on nickel catalysts supported on sepiolite as well as on several different supports. The influence of metal loading and Ni-Cu alloying has been studied as well. The results indicate that catalytic activity and selectivity correlate closely with some textural and/or acid-base properties of the support and selectivity increases with metal loading. Furthermore, as a general rule, Ni-Cu alloying improves in selectivity. 

Although cinchona alkaloids and especially cinchonidine, Cnd, proved to be the most effective chiral modifier for the catalytic system of Pt-alumina, in the liquid phase enantioselective hydrogenations of the carbonyl group in pyruvic acid esters, efforts to understand the mechanism of action of this catalyst system has continued to the present. The efforts may be divided into two categories finding natural modifiers other than cinchona alkaloids and examining new effective amino alcohols, which are modeled after the structure of known cinchona modifiers. 

E21.1 Hydrogenation of particular oil is performed in a liquid phase catalytic reactor (plug flow reactor (PFR)) containing catalytic particles (pellets—spherical diameters) of 1 cm. The external concentration is 1 kmol/L and on the particle surface is 0.1 kmol/L at a superficial velocity of 0.1 m/s. Verify if there are mass effects. There will be a change if the particle diameter is equal to 0.5 cm Neglect the effects in diffusive pores (Fogler, 2000). Additional data ... 

Homogeneous (liquid phase) catalytic oxidations with dioxygen, hydrogen peroxide and other peroxidic reagents constitute an important area of organic synthesis on both laboratory and industrial scale. When dioxygen is employed as terminal oxidant (i.e. the oxidant which appears in the overall stoichiometric equation of the reaction), of special interest is the way in which 0 enters the catalytic cycle,... 

Zhang AM, Dong JL, Xu QH, Rhee HK, Li XL. Palladium cluster filled in inner of carbon nanotubes and their catalytic properties in liquid phase benzene hydrogenation. Catal Today 2004 93-95 347-52. 

Chia, M., Dumesic, J. A., 2011. Liquid-phase catalytic transfer hydrogenation and cycUzation of levulinic acid and its esters to y-valerolactone over metal oxide catalysts. Chemical Communications 47, 12233—12235. 

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