Nickel, catalyst chromate

Nickel catalysts, 77 94, 99, 109 precipitated, 77 121-122 Nickel-catalyzed dinitrotoluene hydrogenation, 25 194 Nickel chelates, 77 117 Nickel chloride hexahydrate, 77 109, 110 Nickel chromate, molecular formula, properties, and uses, 6 562t Nickel-chromium alloy 600, in galvanic series, 7 805t... 

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. 

Several, different, electrochemical oxidations of 26 to 27 have been reported. Using a variety of electrodes (copper, Monel metal, nickel, or silver), 26 was oxidized in aqueous potassium hydroxide solution containing potassium chromate or potassium permanganate, to afford 27 in 70-85% yield.118,119 This electrochemical oxidation has been conducted in aqueous, alkaline solution in the presence of a surfactant, but with added metal catalyst, to give 27 in 85-95% yield.120 Alternatively, the oxidation has been performed by using an anode on which nickel oxide was deposited. This anode, in a solution of 26 at pH >9, with or without nickel salts, afforded 27 in >90% yield.121 A number of additional publications described122-140 other modifications of the... 

Hydrogen peroxide is an efficient oxidizing agent (Section 16-3), particularly in alkaline solution. The excess peroxide is usually decomposed by boiling the alkaline solution the process is hastened by a number of catalysts, including nickel salts, iodide, and platinum black. Schulek and Szakacs removed the excess with chlorine water and then added potassium cyanide to destroy the excess chlorine. Examples of oxidation reactions are the oxidation of Cr(III) to chromate in 2Af sodium hydroxide, Co(II) to Co(III) in bicarbonate solution, Mn(II) to Mn(IV) in the presence of tellurate, and Fe(II) to Fe(III) followed by titration with ascorbic acid. Sodium peroxide, an even more vigorous oxidant, is applied in alkaline fusions. The fusion of chromite ore to form chromate has been critically studied, ... 

Hydrazine is a highly reactive reducing agent that forms shock-sensitive, explosive mixtures with many compounds. It explodes on contact with barium oxide, calcium oxide, chromate salts, and many other substances. On contact with metal catalysts (platinum black, Raney nickel, etc.), hydrazine decomposes to ammonia, hydrogen, and nitrogen gases, which may ignite or explode. 

Many catalyst chemical formulations and geometric shapes are used to promote oxidation-reduction reactions. Chemical types used for VOC oxidation include platinum, platinum alloys, copper chromate, copper oxide, cobalt oxide, chromium oxide, manganese oxide, and nickel. The catalysts are often categorized as platinum metal group (PMG) and base metal (or metal oxide) types. The active catalyst is often supported on an inert carrier such as gamma alumina. Catalyst forms include metal ribbons, mesh and gauze honeycomb monoliths and small beads or particles that can be used in a fixed, fluidized, or moving bed. 

---