Raney nickel commercial

The results of the hydrogenation reactions at 50 min and 130°C of the leached catalysts at 100°C (except commercial) are described in Figure 25.13. The Raney-Nickel commercial catalyst showed the highest conversion ( 60%) followed slightly below of the Cr-Mo promoted catalyst. The other additive catalysts showed a conversion level of about 35%, which was similar to that obtained by the Ni-Raney (100) (leached) catalyst (manufactured in NUCAT lab) at 100°C. The order of activity of the catalysts tested is shown below ... 

The nitro alcohols can be reduced to the corresponding alkan olamines (qv). Commercially, reduction is accompHshed by hydrogenation of the nitro alcohol in methanol in the presence of Raney nickel. Convenient operating conditions are 30°C and 6900 kPa (1000 psi). Production of alkan olamines constitutes the largest single use of nitro alcohols. 

The zwitterion (6) can react with protic solvents to produce a variety of products. Reaction with water yields a transient hydroperoxy alcohol (10) that can dehydrate to a carboxyUc acid or spHt out H2O2 to form a carbonyl compound (aldehyde or ketone, R2CO). In alcohoHc media, the product is an isolable hydroperoxy ether (11) that can be hydrolyzed or reduced (with (CH O) or (CH2)2S) to a carbonyl compound. Reductive amination of (11) over Raney nickel produces amides and amines (64). Reaction of the zwitterion with a carboxyUc acid to form a hydroperoxy ester (12) is commercially important because it can be oxidized to other acids, RCOOH and R COOH. Reaction of zwitterion with HCN produces a-hydroxy nitriles that can be hydrolyzed to a-hydroxy carboxyUc acids. Carboxylates are obtained with H2O2/OH (65). The zwitterion can be reduced during the course of the reaction by tetracyanoethylene to produce its epoxide (66). 

The alkylation of pyridine [110-86-1] takes place through nucleophiUc or homolytic substitution because the TT-electron-deficient pyridine nucleus does not allow electrophiUc substitution, eg, Friedel-Crafts alkylation. NucleophiUc substitution, which occurs with alkah or alkaline metal compounds, and free-radical processes are not attractive for commercial appHcations. Commercially, catalytic alkylation processes via homolytic substitution of pyridine rings are important. The catalysts effective for this reaction include boron phosphate, alumina, siHca—alurnina, and Raney nickel (122). 

Succinic anhydride is manufactured by catalytic hydrogenation of maleic anhydride [108-31-6]. In the most widely used commercial process this reaction is performed in the Hquid phase, at temperatures of 120—180°C and at moderate pressures, in the range of 500—4000 kPa (72—580 psi). Catalysts mentioned in the patent Hterature include nickel (124), Raney nickel (125,126), palladium on different carriers (127,128), and palladium complexes (129). The hydrogenation of the double bond is exothermic Ai/ = —133.89 kJ/mol (—32 kcal/mol) (130). 

Sulfolane (tetramethylenesulfone) [126-33-0] M 120.2, m 28.5 , b 153-154 /18mm, 285 /760mm, d 1.263, n 1.4820. Prepared commercially by Diels-Alder reaction of 1,3-butadiene and sulfur dioxide, followed by Raney nickel hydrogenation. The principle impurities are water, 3-sulfolene, 2-sulfolene and 2-isopropyl sulfolanyl ether. It is dried by passage through a column of molecular sieves. Distd... 

Dimethoxybiphenyl can also be prepared by simply refluxing bis(4-methoxyphenyl)tellurium dichloride with degassed commercial Raney nickel. The yields are, however, lower and less reproducible, and the product may contain some bis(4-methoxyphenyl) telluride. 

In a 5-1. three-necked flask, fitted with an eflicient stirrer (Note 1), a stopper, and a reflux condenser, are placed, in order, 184.2 g. (1 mole) of benzidine (Note 2), 500 ml. of commercial absolute ethanol, about 125 g. of Raney nickel, and 500 ml. of ethanol. The mixture is heated under reflux with stirring for a total of 15 hours (Note 3). The volume is brought to 3 1. with 05% ethanol, and about 150 g. of filter aid ( Super-Cel ) is added with stirring. The mixture is heated to boiling, filtered rapidly... 

The azido mesylate is suspended in absolute ethanol and 80% hydrazine hydrate (3 ml/g of azido mesylate). A small amount (tip of spatula) of Raney nickel (W-2 grade or commercial 50% sponge nickel catalyst from W. R. 

Experiment HGR-13. A 2-ft bed of commercial catalyst was tested as a packed bed of 0.25-in. pellets (see Table I for bed properties). This test was similar to experiment HGR-14 in which the catalyst bed consisted of parallel plates sprayed with Raney nickel. The experiment was... 

The Raney nickel is a very efficient catalyst for the dehydrogenation of 2-butanol into butanone (Scheme 45) with a good selectivity (90%). But, for industrial applications selectivities as high as 99% are required. This can be achieved by poisoning some sites by reaction with Bu4Sn (the best results are obtained with a Sn/Ni ratio of 0.02), which probably occurs first on the sites responsible for the side reactions. The consequence is a slight decrease of the catalytic activity and an increase of the selectivity in 2-butanone which can reach 99%. This catalyst, developed by IFF, has been used commercially in Japan for several years [180]. 

Catalysts - A commercial Raney nickel (RNi-C) and a laboratory Raney nickel (RNi-L) were used in this study. RNi-C was supplied in an aqueous suspension (pH < 10.5, A1 < 7 wt %, particle size 0.012-0.128 mm). Prior to the activity test, RNi-C catalyst (2 g wet, 1.4 g dry, aqueous suspension) was washed three times with ethanol (20 ml) and twice with cyclohexane (CH) (20 mL) in order to remove water from the catalyst. RCN was then exchanged for the cyclohexane and the catalyst sample was introduced into the reactor as a suspension in the substrate. RNi-L catalyst was prepared from a 50 % Ni-50 % A1 alloy (0.045-0.1 mm in size) by treatment with NaOH which dissolved most of the Al. This catalyst was stored in passivated and dried form. Prior to the activity test, the catalyst (0.3 g) was treated in H2 at 250 °C for 2 h and then introduced to the reactor under CH. Raney cobalt (RCo), a commercial product, was treated likewise. Alumina supported Ru, Rh, Pd and Pt catalysts (powder) containing 5 wt. % of metal were purchased from Engelhard in reduced form. Prior to the activity test, catalyst (1.5 g) was treated in H2 at 250 °C for 2 h and then introduced to the reactor under solvent. 10 % Ni and 10 % Co/y-Al203 (200 m2/g) catalysts were prepared by incipient wetness impregnation using nitrate precursors. After drying the samples were calcined and reduced at 500 °C for 2 h and were then introduced to the reactor under CH. 

Instead of using high-temperature melting to make the precursor alloys, an alternative wet chemistry technique has been proposed where nickel(O) and aluminum coordination compounds are blended together and treated to give nanocrystalline NiAlx alloys with 1 < x < 3 [48], The alloys are leached in the same way as standard skeletal catalysts. Catalysts with higher activity than commercially available Raney nickel have been prepared by this technique, with the activity attributed to the finer structure and homogeneity of the alloys [48,49],... 

Up to date, the scientists involved in these investigations used only few commercial catalysts, predominantly Pd/C, Pt/C, Pt02, or Raney nickel. But except for a few cases, these catalysts are not selective enough and only a mixture of diastereomers results from the reactions. The separation of the pure diastereomers is expensive and requires a lot of energy and reagents. Even more complicate is the case of diastereoselective oxidation. 

Compounds 3 (when R=He) and 5 are available In commercial quantities. Compound 4 may also be purchased or prepared In high yield via hydrogenation of 3 over a promoted Raney nickel catalyst (C. 6. Coe, unpublished results). The condensation of 4 with distilled acryloyl chloride proceeds In over 95X yield. 

Many catalysts, certainly those most widely used such as platinum, palladium, rhodium, ruthenium, nickel, Raney nickel, and catalysts for homogeneous hydrogenation such as tris(triphenylphosphine)rhodium chloride are now commercially available. Procedures for the preparation of catalysts are therefore described in detail only in the cases of the less common ones (p. 205). Guidelines for use and dosage of catalysts are given in Table 1. 

To a solution of 148 g. (0.845 mole) of methyl 7-methyl-7-nitrovalerate (p. 86) in 500 ml. of commercial absolute ethanol (total volume about 632 ml.) in a 2.5-1. rocking high-pressure bomb is added 12.5-25.0 g. (Note 1) of W-5 2 Raney nickel catalyst (Note 2), previously rinsed with absolute ethanol. The bomb head and fittings are placed in position, including a thermocouple attached to a semi-automatic heating control (Micromax). Hydrogen is introduced into the bomb until the pressure reaches 1000 lb. per sq. in. (Note 3). 

The checkers have found that commercial grade Raney nickel (Gilman Paint and Varnish Company) is a satisfactory substitute for W-5 catalyst. The yields obtained with the two catalysts are identical, but the hydrogenation requires 2-3 hours with commercial catalyst compared with 1-1.5 hours for W-5 catalyst. 

Phenanthrene purified by the sodium treatment was found superior to that from the azeotropic distillation, but both products gave satisfactory results. A good grade of commercially available phenanthrene ( white label grade supplied by the Eastman Kodak Company), although recrystallized and treated with Raney nickel, resisted hydrogenation under the described conditions. 

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