Of cadmium metal

The apparent United States consumption of cadmium in 1988 was estimated to be 3620 t. Of the 2482 t imported, over 85% came from Canada, Mexico, Germany, and AustraUa. The principal domestic producers and suppHers of cadmium metal are ASARCO, Inc. Big River Zinc Corp. Jersey Miniure Zinc Co. and Zinc Corp. of America. 

Naturally occurring cadmium compounds are limited to the rare minerals, greenockite [1317-58 ] CdS, and otavite (1), an oxycarbonate, but neither is an economically important source of cadmium metal or its compounds. Instead, cadmium compounds are more usually derived from metallic cadmium [7440-43-9] which is produced as a by-product of lead—2inc smelting or electrolysis (see Cadmiumand cadmium alloys). Typically, this cadmium metal is burnt as a vapor, to produce the brown-black cadmium oxide [1306-19-0], CdO, which then acts as a convenient starting material for most of the economically important compounds. 

Electrodeposition of CdS has been carried out from aqueous and non-aqueous solutions containing precursors of both elements as well as by anodization of cadmium metal in sulfide solutions. 

Nedoluzhko AI, Shumihn lA, Nikandrov VV (1996) Coupled action of cadmium metal and hydrogenase in formate photodecomposition sensitized by CdS. J Phys Chem 100 17544-17550... 

Laboratory studies with mice and rats have conclusively demonstrated that the injection of cadmium metal or salts causes malignancies (sarcoma) at the site of injection and testicular tumors. However, the simultaneous administration of zinc is protective against sarcoma and interstitial cell tumor development (USEPA 1980). In rats, no dose-related increases in tumors were found at maximum oral daily doses of 4.4 mg Cd/kg BW (USPHS 1993). Among humans, the available epidemiological evidence is not sufficient to conclude that cadmium is definitely implicated as a carcinogen (USEPA 1980 Nomiyama 1982), although cadmium exposure is associated with lung cancer in humans (Shimada et al. 1998). 

Cadmium iodide is prepared by the addition of cadmium metal, or its oxide, hydroxide, nitrate or carbonate to hydriodic acid ... 

Cadmium sulfate is prepared by the reaction of cadmium metal or its oxide or hydroxide with dilute sulfuric acid ... 

The properties of Cd species formed by the dissolution of cadmium metal in molten cadmium halides and at electrode interface were investigated [216]. 

When CdY was heated at 450° C in a helium stream, cadmium was removed from the zeolite cavities and the metal was deposited at the exit of the reactor. The CdY thus treated showed no catalytic activity. Then the temperature of the pretreatment was lowered to the reaction temperature of 395°C, and the conversion cited in Table I was observed. Even at this pretreatment temperature, the small amount of cadmium metal appeared at the exit of the reactor. This may be the cause of the large deviation of CdY from the linear relationship. 

In retrospect, we also explain as being due to the formation of n-n+ junctions the improvement in the conversion efficiency of solar cells made with hot-pressed, polycrystalline n-CdSe upon diffusion of cadmium metal, and n-type dopant, into the boundaries.43... 

This preparation of cadmium rhenium(V) oxide consists of two steps. The first step is the oxidation of rhenium metal in a stream of oxygen to its heptaoxide Re207. The second step is the vapor-phase reaction of cadmium metal and rhenium(VII) oxide. 

Ni-Cd cells — The nickel-cadmium cell is a secondary - battery that has a nominal cell potential of 1.20-1.25 V. The negative electrode comprises nickel hydroxide-nickel oxyhydroxide, the positive electrode is cadmium, and the electrolyte solution is based on aqueous potassium hydroxide (KOH, 32% in water). At the anode, the discharge reaction is the oxidation of cadmium metal to cadmium hydroxide with the release of two electrons [i] ... 

Exposure to small doses of cadmium metal or ions can increase the risk of cancers, particularly breast cancer. Smoking doubles the normal natural intake of Cd1... 

Kardam, A., Goyal, R, Arora, J.K., Raj, K.R., and Srivastava, S. 2009. Novel biopolymeric material Synthesis and characterization for decontamination of cadmium metal from waste water. National Academic and Science Letters, 32(5 and 6) 179-81. 

While this state, in the form of M2+ ions, is not of great importance for Zn and Cd, it does exist in a few stable compounds. Zinc metal dissolves in molten ZnCl2 (500-700°C) to afford, on cooling, a yellow, diamagnetic glass. Similarly, Cd dissolves in molten CdCl2. Reaction of cadmium metal with molten Cd(AlCLt)2 affords crystalline Cd2(AlCl4)2, in which Cd2+ ions (Cd—Cd distance, 2.576 A) are found. 

Calculate the mass of silver metal that can be produced by the action of 12.2 g of cadmium metal on excess aqueous silver nitrate. 

R2Cd compounds were first obtained by the direct reaction of cadmium metal with alkyl halides. Unfortunately, this method is limited and typically does not readily yield pure products. However, the direct method is facilitated by the use of highly activated cadmium slurries. " ... 

Organocadmate derivatives of the type [RCdX2] (R = Me, Et, Bn, CF3, Ph, CeFs X = Cl, Br, 1) have been obtained by the direct electrochemical oxidation of cadmium metal in the presence of RX and [Pr4N]pC] (equation 25). Other organocadmate derivatives, for example, [(CF3)Cdl2] and [(C6F5)CdBr2] , are also known. 

In 2008, American consumption of cadmium metal totaled approximately 3.87 million. 

Together, the annual output of the 2 factories is over 700 tonnes of cadmium metal of a purity of 99.99 % by weight and more than 650 tonnes of nickel in the form of iron nickel residues (1,900 tonnes) or ferro-nickel. The balance is made of plastic materials (cases of the industrial batteries, plastic shells around the power packs etc.), of scrap iron (metallic cases of the industrial batteries, iron residues coming form the distillation of negative pocket plates). These products are valorised at a market value either for energy production or scrap. 

The best preparation of R2Cd compounds is by treatment of the anhydrous cadmium halide with RLi or RMgX. The reaction of cadmium metal with alkyl iodides in dimethylformamide or (CH3)2SO gives RCdl in solution. 

The excess sodium was killed with methanol and crystalline cadmium was apparently isolated. No quantitative analysis of the product was made, but x-ray diffraction confirmed the presence of cadmium metal. 

The species Cd and are known, for example, in solutions of cadmium metal in... 

Cd NMR relaxation data indicate that the addition of cadmium metal to CdU results in the formation of Cd " and Cd, with the monomeric species having a half-life of about 10ps. "... 

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