Nickel complexes arsenic oxides

Early catalysts for acrolein synthesis were based on cuprous oxide and other heavy metal oxides deposited on inert siHca or alumina supports (39). Later, catalysts more selective for the oxidation of propylene to acrolein and acrolein to acryHc acid were prepared from bismuth, cobalt, kon, nickel, tin salts, and molybdic, molybdic phosphoric, and molybdic siHcic acids. Preferred second-stage catalysts generally are complex oxides containing molybdenum and vanadium. Other components, such as tungsten, copper, tellurium, and arsenic oxides, have been incorporated to increase low temperature activity and productivity (39,45,46). 

The tertiary triarsine complexes of nickel(II) halides have been more thoroughly investigated. They have formulas [Ni(TA)X2J, and are not dissociated in solution 15, 192). The fact that oxidation affects the metal but not the arsenic must mean that all arsenic atoms are coordinated to the... 

Some planar complexes containing arsenic can be prepared, o-Phenylenebisdimethylarsine (diarsine) reacts with nickel carbonyl to form Ni(CO)2(diarsine) (70). Oxidation of this complex with iodine gives a red, diamagnetic, planar complex, Ni(diarsine)12. The corresponding bromides and chlorides could not be purified and appear to be much less stable (70). 

The production of coke by the carbonization of bituminous coal leads to the release of chemically complex emissions from coke ovens that include both gases and particulate matter of varying chemical composition. The chemical and physical properties of coke oven emissions vary depending on the constituents. The emissions include coal tar pitch volatiles (e.g., particulate polycyclic organic matter, polycyclic aromatic hydrocarbons, and polynuclear aromatic hydrocarbons), aromatic compounds (e.g., benzene and jS-naphthyl amine), trace metals (e.g., arsenic, beryllium, cadmium, chromium, lead, and nickel), and gases (e.g., nitric oxides and sulfur dioxide). 

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