Nickel solution properties

To optimize the use of the amorphous sodium titanate powders as catalyst substrates, it is important to fully characterize the ion-exchange properties of the material. Further, the solution properties of the active metal to be loaded onto the support will be an important parameter in the control of the adsorption process. For example, exposure of sodium titanate to a nickel salt solution does not guarantee that nickel will be loaded onto the sodium titanate, or that the nickel, if loaded, will be dispersed on an atomic level. Sodium titanate only behaves as a cation exchange material under certain pH conditions. The solution pH also influences the hydrolysis and speciation of dissolved nickel ions (3), which can form large polymeric clusters or colloidal particles which are not adsorbed by the sodium titanate via a simple ion-exchange process. 

This paper describes some of our initial studies of the solution properties of sodium titanate powders in order to understand and control the metal-loading process in the preparation of a heterogeneous catalyst from the materials. The purposes of this study are 1) to define the pH and concentration regimes in which nickel is loaded onto sodium titanate as monomeric ions via ion exchange, as polymeric clusters via hydrolysis, or as discrete particles of colloidal nickel hydroxide, and 2) to characterize the catalysts with respect to the dispersion of the active metal under reaction conditions by measuring the activity and selectivity of the catalysts for a known "structure-sensitive" reaction, the hydrogenolysis of n-butane. 

The solution properties of the 1 1 complexes of nickel(II) with 2,2 6, 2"-terpyridine are poorly characterized this is particularly unfortunate, since the nickel(II)-2,2 6, 2"-terpyridine system has been widely studied in investigations into the binding of 2,2 6, 2"-terpyridine to metal ions. The rate of the reaction ... 

Costes J. P. and Laurent J. P., Solution properties of dinuclear copper and nickel complexes and their mononuclear precursors, Inorg. Chim. Acta, 134 (1987) pp.245-248. 

In contrast, when Ni(CT)Cl2 or Ni(CT)Br2 is dissolved in water, it converts to a planar, diamagnetic complex which acts as a di-univalent electrolyte. Also, the nickel (II) ion in Ni(CT)2+ will not combine with NH3 when dissolved in aqueous solution 11). These observations present a number of disturbing features. The failure of H2O and NH3 to coordinate is inferred from the fact that the solution properties are typical of planar nickel(II). Both NH3 and H2O occupy positions much higher in the spectrochemical series than Cl or Br. Consequently, if either of these neutral molecules were coordinated, the nickel atom would surely exist in its paramagnetic triplet state. 

Bis(2,4,4-trimethylpentyl)phosphinic add (CYAN EX 272) is extremely selective toward extracting cobalt from aqueous cobalt/nickel solutions [56, 57], and consequently, the corresponding bis(2,4,4-trimethylpentyl)phosphinate salt prepared form entry 6 [58] may have some unique selective metal complexing properties. 

Substances showing catalytic waves in ammoniacal cobalt or nickel solutions< > must fulfil another condition beside the two conditions mentioned above the substance has to form a complex-compound with cobalt and other components of the solution. Moreover, the acid properties of this complex and its adsorbability also seem to be of importance. The substances showing a catalytic effect of this type usually contain at least an atom of sulphur in their molecule (e.g. cysteine, dithiopyrimidine or proteins). Whether or not the presence of sulphur in the catalytically active molecule is a sufficient condition has yet to be decided. It was shown that e.g. gelatin or casein containing little or no sulphur atoms do not produce any catalytic wave of this type. Similarly, in the series of hydantoin, thiohydantoin and dithiohydantoin as well as pyrimidine, thiopyrimidine, and dithiopyrimidine, the catalytic effect was only observed for the thioderivative and it increased with the number of sulphur atoms in the molecule. 

This system includes four elements Rs - resistance of 0.5M NaCl solution. Ret - electric charge transfer resistance for phase boundary of nickel - solution, CPEai - constant phase element characterizing the electrical properties of the double layer at the interface, and the element W - Warburg impedance, which characterizes the control of corrosion processes by diffusion of mass in the area of the electrolyte at the metal surface. 

E. J. Rubin and R. Babaoian, A Correlation of the Solution Properties and the Electrochemiceil Behavior of the Nickel Hydroxide Electrode in Binary Aqueous Alkali Hydroxides, J. Electrochem. Soc. 118 428 (1971). 

Inframat Corporation (2003a) had demonstrated that WC/Co-Ni nanocoating could be obtained via electrocodeposition of WC/Co nanoparticles from a nickel sulfamate colloidal solution. Properties of this WC/Co-Ni nanocoating were compared with conventional electroplated hard chrominm and thermal sprayed WC/Co. Benefits derived from this nanocoating inclnde high hardness and wear resistance, low coefficient of friction, and a smooth deposited snrface. A US... 

C. It occurs in natural gas. May prepared by reduction of ethene or ethyne by hydrogen under pressure in the presence of a nickel catalyst, or by the electrolysis of a solution of potassium elhanoate. It has the general properties of the paraffins. Used in low-temperature refrigeration plant. 

Nickel—Copper. In the soHd state, nickel and copper form a continuous soHd solution. The nickel-rich, nickel—copper alloys are characterized by a good compromise of strength and ductihty and are resistant to corrosion and stress corrosion ia many environments, ia particular water and seawater, nonoxidizing acids, neutral and alkaline salts, and alkaUes. These alloys are weldable and are characterized by elevated and high temperature mechanical properties for certain appHcations. The copper content ia these alloys also easure improved thermal coaductivity for heat exchange. MONEL alloy 400 is a typical nickel-rich, nickel—copper alloy ia which the nickel content is ca 66 wt %. MONEL alloy K-500 is essentially alloy 400 with small additions of aluminum and titanium. Aging of alloy K-500 results in very fine y -precipitates and increased strength (see also Copper alloys). 

Compounds containing such metals as copper, barium, lead, molybdenum, and nickel generally are not used in processing solutions. However, trace quantities of certain metal dopants occasionally are used to impart desired soHd-state and photographic properties to emulsion grains. Because of its... 

The extraction of metal ions depends on the chelating ability of 8-hydroxyquinoline. Modification of the stmcture can improve its properties, eg, higher solubility in organic solvents (91). The extraction of nickel, cobalt, copper, and zinc from acid sulfates has been accompHshed using 8-hydroxyquinohne in an immiscible solvent (92). In the presence of oximes, halo-substituted 8-hydroxyquinolines have been used to recover copper and zinc from aqueous solutions (93). Dilute solutions of heavy metals such as mercury, ca dmium, copper, lead, and zinc can be purified using quinoline-8-carboxyhc acid adsorbed on various substrates (94). 

Bina Selenides. Most biaary selenides are formed by beating selenium ia the presence of the element, reduction of selenites or selenates with carbon or hydrogen, and double decomposition of heavy-metal salts ia aqueous solution or suspension with a soluble selenide salt, eg, Na2Se or (NH 2S [66455-76-3]. Atmospheric oxygen oxidizes the selenides more rapidly than the corresponding sulfides and more slowly than the teUurides. Selenides of the alkah, alkaline-earth metals, and lanthanum elements are water soluble and readily hydrolyzed. Heavy-metal selenides are iasoluble ia water. Polyselenides form when selenium reacts with alkah metals dissolved ia hquid ammonia. Metal (M) hydrogen selenides of the M HSe type are known. Some heavy-metal selenides show important and useful electric, photoelectric, photo-optical, and semiconductor properties. Ferroselenium and nickel selenide are made by sintering a mixture of selenium and metal powder. 

Elements that can dissolve in copper, such as zinc, tin, and nickel for example, increase annealed strength by varying amounts depending on the element and the quantity in solution. The effect of selected solution hardening elements on tensile properties of annealed copper aUoys is iUustrated by the data in Table 4, where the yield strength is the stress at 0.2% offset strain in a tensile test. 

Alpha—beta aluminum alloys respond to heat treatment with a general improvement of mechanical properties. Heat treatment is accompHshed by heating to 815—870°C, quenching in water, and reannealing at 370—535°C, depending on the size and section of the casting. Different combinations of strength, hardness, and ductility can be obtained. Some nickel in aluminum bronze is in soHd solution with the matrix and helps refine the precipitate, and a smaller amount is in the K-intermetaUic compound. 

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