Sulfate catalysts

The reaction is used for the chain extension of aldoses in the synthesis of new or unusual sugars In this case the starting material l arabinose is an abundant natural product and possesses the correct configurations at its three chirality centers for elaboration to the relatively rare l enantiomers of glucose and mannose After cyanohydrin formation the cyano groups are converted to aldehyde functions by hydrogenation m aqueous solution Under these conditions —C=N is reduced to —CH=NH and hydrolyzes rapidly to —CH=0 Use of a poisoned palladium on barium sulfate catalyst prevents further reduction to the alditols... 

Methyl violet [8004-87-3] Cl Basic Violet 1 (17), is made by the air oxidation of dimethyl aniline in the presence of salt, phenol, and a copper sulfate catalyst. Initially, some of the dimethyl aniline is oxidized to formaldehyde and /V-methyl aniline under those conditions. The formaldehyde then reacts with dimethyl aniline to produce N,N,]S7,1S7-tetramethyldiaminodiphenylmethane, which is oxidized to Michler s hydrol [119-58-4]. The hydrol condenses with... 

Blue tungsten oxide and combiaations thereof (106—113) have been the subject of a number of patents, as have copper(II) fluoborate (114) and alkaH metal or ammonium sulfate-hydrogen sulfate catalysts (115,116). 

Catalytic hydrogenation of dimethyl 3-methyl-3//-3-benzazepine-2,4-dicarboxylate (10) to the 1,2,4,5-tetrahydro derivative with hydrogen and a palladium-barium sulfate catalyst, followed by treatment of the reaction mixture with iodomethane in refluxing methanol, yields a mixture of the 2,4-dicarboxylic acid 11 and the methiodide salt 12.24... 

The chemical method for the determination of the chemical oxygen demand of non-saline waters involves oxidation of the organic matter with an excess of standard acidic potassium dichromate in the presence of silver sulfate catalyst followed by estimation of unused dichromate by titration with ferrous ammonium sulfate. Unfortunately, in this method, the high concentrations of sodium chloride present in sea water react with potassium dichromate producing chlorine ... 

Sapper An obsolete process for making phthalic anhydride by oxidizing o-xylene, using a mercury sulfate catalyst. Invented by E. Sapper in 1891 in the course of searching for a commercial route to indigo, and used until the catalytic gas-phase oxidation of naphthalene was introduced in 1925. 

Acetic acid analogs can also be formed from a one-step C-H activation process using a palladium sulfate catalyst.15 A free radical process was ruled out for this formal eight-electron oxidation due to the high selectivities observed (90% based on methane converted) (Equation (7)). 

These reactions can also be performed over a strong acid catalyst at reaction temperatures that are lower than over zeolites. Because of this, isomerization of M-butane over Zr02-supported sulfate catalysts was initially proposed by Hino and Arata. They proposed these catalysts as being effective in butane isomerization at room temperature, a reaction that does not take place, even in 100% sulphuric acid. For this reason, these catalysts were considered as solid superacids, since they are active and selective in the isomerization of n-butane to isobutane at... 

Figure 4. Rate/concentration as a function of concentration for Mequinenza lignite, nickel sulfate catalyst, 275 C, average H2S partial pressure 0.14 MPa.

Hydrogenation of dimeric nitroso compounds with a palladium-on-barium sulfate catalyst [17] (Eq. 46). 

The preirradiated foam was treated with monomer solution containing ferrous ammonium sulfate catalyst under the conditions described above, but the nitrogen purge was omitted. The samples were removed from the monomer solution and passed between rubber rollers to remove excess monomer and then placed in an air-tight container. The container was evacuated, and grafting of the monomer-wetted polymer was allowed to proceed in vacuo for about 16 hours at room temperature. 

The hydration of acetylene produces acetaldehyde which then can be converted to acetic acid and other derivatives. The process is similar to olefin hydration employing a sulfuric acid solution containing also a mercurous sulfate catalyst. 

This method was developed to replace the hazardous mercury catalyst required in the original mercuric oxide Kjeldahl method. It has been evaluated through an interlaboratory comparison of catalysts and has been adopted as the official replacement for the mercuric-oxide catalyzed Kjeldahl method. An inter-laboratory evaluation (Berner, 1990) indicated that this method (which uses the copper/titanium catalyst mixture) produces results more closely in agreement with the mercuric oxide catalyst method than methods using a copper sulfate catalyst. As a result of this study, mercuric... 

The hydrobromide of l-(p-hydroxyphenyl)-2-(p-phenylbutylamino)propanone-1 was suspended in very pure methanol and shaken with a 10% palladium hydroxide barium sulfate catalyst in contact with, hydrogen. After rather more than 2 mols of hydrogen had been taken-up the hydrogenation stopped. The l-(p-hydroxyphenyl)-2-(3-phenylbutylamino)propanol-l, was filtered, washed with methanol and evaporated, melting point 110-111°C. 

Sulfonation of pyridine A-oxide requires the use of 20% fuming sulfuric acid and a mercuric sulfate catalyst with prolonged heating at 230°. Under these conditions, the main product is the 3-sulfonic acid (40-45%) together with small amounts of the 2- (0.5-1%) and 4-sulfonic acids (2-2.5%).214 2,6-Lutidine V-oxide reacts under similar conditions, substitution taking place at C-3.215... 

Sulfated catalyst activity was determined with the S02 free feedstream in the absence of water The light-off temperatures reported in Fig 3a for propene oxidation show that sulfation by SO2 induces the same effects on catalyst activity than SO2 in the feedstream in the course of the oxidation reaction (Fig 1b). Thus Pt-Rh catalyst activity is not affected by sulfation while monometallic platinum catalysts are far less active after sulfur storage with 20 ppm SC>2 We must note also that a small inhibiting effect appears after sulfur storage with 4 ppm SO2. 

The amount of S03 picked up by this catalyst is 3% of its initial weight. This, we believe, is because of a lack of surface area and low pore volume. In Zone D when the sulfated catalyst is reacted with H2 the reduction is very unsatisfactory. The rate of reduction is slow and the material does not release all the absorbed sulfur even after 10 minutes of H2 reduction. 

When impregnated with Ce(N03)3 solution and calcined the resulting catalysts are extremely active towards SOx abatement (Table I, Figure 4). The solid solution spinel catalyst is nearly 25% more active than the stoichiometric spinel catalyst. This can be explained by assuming that -MgO- structural fragments of the spinel are the chemisorption active sites (1). There are more active sites in Mg2Al20c than in MgA1 04. We also see that the catalyst prepared by co-precipitation method is 4 times more active than the catalyst prepared by the thermal co-condensation method. In Zone D we see that the sulfated catalyst is very effectively reduced by H. Nearly 70% of the absorbed species is reduced within 2 min. of reduction. 

Oxidation of sodium sulfite with cobaltous sulfate catalyst... 

Another commercial aldehyde synthesis is the catalytic dehydrogenation of primary alcohols at high temperature in the presence of a copper or a copper-chromite catalyst. Although there are several other synthetic processes employed, these tend to be smaller scale reactions. For example, acyl halides can be reduced to the aldehyde (Rosemnund reaction) using a palladium-on-barium sulfate catalyst. Formylation of aryl compounds, similar to hydrofomiylation, using HCN and HQ (Gatterman reaction) or carbon monoxide and HQ (Gatterman-Koch reaction) can be used to produce aromatic aldehydes. 

Quinoline (Coll. Vol. i, 456) The Skiaup synthesis is earned out with funung sulfuric add and copper sulfate catalyst, at 135-154°. Kikebgov and Zasosov, Khim. Farm. Prom. 1934, No. i, 40 [C. A. 28, 5454 (1934)]. 

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