Iron, carbonyl compounds nickel

The catalyst deactivation studies described here were carried out in 300 cm.. gas-sparged, stirred autoclaves and in a nominal 10 ton (CH30H)/day pilot-plant, bubble-column reactor. The details of the design and operation of these reactor systems have been reported elsewhere [refs. 4,5]. AH of the present studies were carried out with a feed gas that is referred to as "CO-Rich Gas , with a molar composition of H2 35%, CO-51 %, C02-13% and N2 1%- Its stoichiometric ratio, defined as H2/(CO+1.5002), is 0.5. A typical stoichiometric ratio for the feed to a conventional methanol reactor Is about 2.6, well on the H2-rich side of 2.0, the ratio tor exact stoichiometric equivalence. The feed concentrations of known poisons such as hydrogen sulfide, carbonyl sulfide, chlorine compounds, iron carbonyl and nickel carbonyl were below the limits of detection, 50 ppb, 50 ppb, 10 ppb, 50 ppb and 50 ppb, respectively. 

Exposure to metal carbonyls can present a serious health threat. Nickel carbonyl is considered to be one of the most poisonous inorganic compounds. However, the toxicological information available on metal carbonyls is restricted to the mote common, commercially important compounds such as Ni(CO)4 and Ee(CO). Other metal carbonyls are considered potentially dangerous, especially ia the gaseous state, by analogy to nickel and iron carbonyls. Data concerning toxicological studies on a few common metal carbonyls are Hsted ia Table 6 (185). Additional toxicity data are OSHA personal exposure limits (PEL) for Ee(CO) this is 8 h at 0.1 ppm, whereas for the much more toxic Ni(CO)4 it is 8 h at 0.001 ppm, with a toxic concentration TCLq low (of 7 mg/m ) for human inhalation. 

Kohlenozyd, n, carbon monoxide, -eisen, n. iron carbonyl, -gas, n. carbon monoxide gas. -hamoglobin, n. compound of carbon monoxide with hemoglobin, -kalium, n. potassium carboxide, potassium hexacar-bonyl. -knallgas, n, explosive mixture of carbon monoxide and oxygen, -nickel, n. nickel carbonyl. 

In contrast to the chalcogen-bridged complexes, no similar oxygen-bridged compounds of iron, cobalt, or nickel exist. However, we obtained such oxo or i-ol-carbonyl complexes of chromium and its homologs, as well as of rhenium. The compounds are the products of the reactions of the respective metal carbonyls with bases (VII). 

Several compounds of iron and carbon monoxide are known. Mond and Quincke6 were the first to obtain experimental evidence of the existence of volatile iron carbonyls they succeeded in volatilising reduced iron in a current of carbon monoxide to a very slight extent, and concluded that a tetracarbonyl, Fe(CO)4, had been produced corresponding to the nickel analogue, Ni(CO)4, which had been prepared the previous year.7 A few months later Mond and Danger 8 succeeded m isolating the iron carbonyl, and found it to be not the tetra but the penta derivative. 

Nickel occurs, with iron, in meteorites. Its principal ores are nickelite, NiAs, millerite, NiS, and pentlandite, (Ni,Fe)S. The metal is produced, as an alloy containing iron and other elements, by roasting the ore and reducing with carbon. In the purification of nickel by the Mond process the gaseous compound nickel carbonyl, Ni(CO)4, is man ufactured and then decomposed. 

There is also information on the formation of bridged complexes on substitution of one ring in nickelocene. Thus nickel and iron carbonyls produce the following compounds on reacting in benzene (236-240) ... 

This decomposition does not take place if a solution of iron pentacarbonyl in nickel carbonyl is exposed to light, perhaps because of the formation of a stable compound of the formula NiFe(CO)g (Dewar). 

Vanhoye and coworkers [402] synthesized aldehydes by using the electrogenerated radical anion of iron pentacarbonyl to reduce iodoethane and benzyl bromide in the presence of carbon monoxide. Esters can be prepared catalytically from alkyl halides and alcohols in the presence of iron pentacarbonyl [403]. Yoshida and coworkers reduced mixtures of organic halides and iron pentacarbonyl and then introduced an electrophile to obtain carbonyl compounds [404] and converted alkyl halides into aldehydes by using iron pentacarbonyl as a catalyst [405,406]. Finally, a review by Torii [407] provides references to additional papers that deal with catalytic processes involving complexes of nickel, cobalt, iron, palladium, rhodium, platinum, chromium, molybdenum, tungsten, manganese, rhenium, tin, lead, zinc, mercury, and titanium. 

Alkyne cyclotrimerization occurs at various homogeneous and heterogeneous transition metal and Ziegler-type catalysts [7], Substituted benzenes have been prepared in the presence of iron, cobalt, and nickel carbonyls [8] as well as trialkyl- and triarylchromium compounds [9]. Bis(acrylonitrile)nickel [10] and bis(benzonitrile)palladium chloride [11] catalyze the cyclotrimerization of tolane to hexaphenylbenzene. NiCl2 reduced by NaBH4 has been utilized for the trimer-ization of 3-hexyne to hexaethylbenzene [12]. Ta2Cl6(tetrahydrothiophene)3 and Nb2Cl6(tetrahydrothiophene)3 as well as 7 -Ind-, and 77 -Ru-rhodium... 

The first compound containing carbon monoxide as a ligand was another platinum chloro complex, reported in 1867. In 1890, Mond6 reported the preparation of Ni(CO)4, a compound that became commercially useful for the purification of nickel. Other metal CO ( carbonyl ) complexes were soon obtained particularly notable was the work on iron carbonyls beginning around 80 years ago by Hieber.7... 

Nickel and iron powder. Fine Ni and Fe powder is obtained by hydrogen reduction of the oxide or decomposition of carbonyl compounds. 

Alcan 756 C.l. 77775 Carbonyl nickel powder CCRIS 427 EINECS 231-111-4 EL12 Fibrex Fibrex P HSDB 1096 Ni 0901-S Ni 270 Ni 4303T Nichel Nickel 200 Nickel 201 Nickel 205 Nickel 207 Nickel 270 Nickel catalyst Nickel compounds Nickel, elemental Nickel, elemental/metal Nickel particles Nickel sponge NP 2 Raney alloy Raney nickel RCH 55/5. Metallic element, used in electroplating, as a hydrogenation catalyst and in iron- and copper-based alloys. Metal mp = 1453° bp (calc) = 2732° d= 8.908. Atomergic Chemetals Inco, Europe Lancaster Synthesis Co. Sigma-Aldrich Fine Chem. 

Thomas succeeded in forming 2-30nm particles of cobalt with a narrow size distribution by decomposing cobalt carbonyl compounds in the presence of suitable surface-active reagents [50]. By the same procedure, iron and nickel particles were prepared. Papirer et al. studied the decomposition of a toluene solution of Co2(CO)8 in the presence of a surface-active reagent and found that at least two factors are responsible for the formation of particles with an extremely narrow size distribution the division of the system into microreactors and a diffusion-controlled growth mechanism of the individual particles [51]. 

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