Mercury oxide catalysts

Pilot testing of mercury oxidation catalysts for upstream of wet FGD systems, G. M. Blythe, Quarterly Technical Progress Report, April-June 2006, URS Corporation, Austin, Texas. 

Manufacture and Processing. Until World War II, phthaUc acid and, later, phthaUc anhydride, were manufactured primarily by Hquid-phase oxidation of suitable feedstocks. The favored method was BASF s oxidation of naphthalene [91-20-3] by sulfuric acid ia the presence of mercury salts to form the anhydride. This process was patented ia 1896. During World War I, a process to make phthaUc anhydride by the oxidation of naphthalene ia the vapor phase over a vanadium and molybdenum oxide catalyst was developed ia the United States (5). Essentially the same process was developed iadependendy ia Germany, with U.S. patents being granted ia 1930 and 1934 (6,7). 

The chemistry of alkynes is dominated by electrophilic addition reactions, similar to those of alkenes. Alkynes react with HBr and HC1 to yield vinylic halides and with Br2 and Cl2 to yield 1,2-dihalides (vicinal dihalides). Alkynes can be hydrated by reaction with aqueous sulfuric acid in the presence of mercury(ll) catalyst. The reaction leads to an intermediate enol that immediately isomerizes to yield a ketone tautomer. Since the addition reaction occurs with Markovnikov regiochemistry, a methyl ketone is produced from a terminal alkyne. Alternatively, hydroboration/oxidation of a terminal alkyne yields an aldehyde. 

The mercury penetration approach is based on the fact that liquid mercury has a very high surface tension and the observation that mercury does not wet most catalyst surfaces. This situation holds true for oxide catalysts and supported metal catalysts that make up by far the overwhelming majority of the porous commercial materials of interest. Since mercury does not wet such surfaces, the pressure required to force mercury into the pores will depend on the pore radius. This provides a basis for measuring pore size distributions through measurements of the... 

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. 

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... 

Alkenes can be oxidized to ketones of the same chain length by using salts of copper, palladium, and mercury as catalysts and air, electrolysis [120], hydrogen peroxide, or chromium compounds as oxidants [60, 65, 140, 565] (equation 90). 

SULKOL (7704-34-9) Combustible solid (flash point 405°F/207°C). Finely divided dry material forms explosive mixture with air. The vapor reacts violently with lithium carbide. Reacts violently with many substances, including strong oxidizers, aluminum powders, boron, bromine pentafluoride, bromine trifluoride, calcium hypochlorite, carbides, cesium, chlorates, chlorine dioxide, chlorine trifluoride, chromic acid, chromyl chloride, dichlorine oxide, diethylzinc, fluorine, halogen compounds, hexalithium disilicide, lampblack, lead chlorite, lead dioxide, lithium, powdered nickel, nickel catalysts, red phosphorus, phosphorus trioxide, potassium, potassium chlorite, potassium iodate, potassium peroxoferrate, rubidium acetylide, ruthenium tetraoxide, sodium, sodium chlorite, sodium peroxide, tin, uranium, zinc, zinc(II) nitrate, hexahydrate. Forms heat-, friction-, impact-, and shock-sensitive explosive or pyrophoric mixtures with ammonia, ammonium nitrate, barium bromate, bromates, calcium carbide, charcoal, hydrocarbons, iodates, iodine pentafluoride, iodine pentoxide, iron, lead chromate, mercurous oxide, mercury nitrate, mercury oxide, nitryl fluoride, nitrogen dioxide, inorganic perchlorates, potassium bromate, potassium nitride, potassium perchlorate, silver nitrate, sodium hydride, sulfur dichloride. Incompatible with barium carbide. 

The mixture of mercury oxide, boron trifluoride-ether, and trifluoroacetic acid is a particularly effective catalyst for hydration of alkynes 84 mixtures of mercury oxide and boron trifluoride88 and of mercury oxide with sulfuric acid86 have also been used. Addition to acid-sensitive acetylenes is carried out under neutral conditions by means of mercuriacetamide or mercuri-/7-toluenesulfonamide.87 Acid exchange resins loaded with mercury ions can also be used for addition of water to alkynes.88... 

In the presence of an acid catalyst such as boron trifluoride or mixtures of mercury oxide and boron trifluoride two molecules of alcohol are added, the products being acetals 197"200... 

For this reaction the catalyst may be boron trifluoride-ether and mercury oxide. However, boron trifluoride and mercury oxide can be used as catalyst in such cases only with methanol — other monohydric alcohols are converted into polymeric products thereby in an obscure reaction. Nevertheless, if a little trichloroacetic acid is added to these catalyst mixtures even the higher alcohols react normally.205... 

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