Alloy leaching

Medium Ni2Al3 phases having NiAl3 peritecticallv grown on them in ground slowly cooled powder alloys leach faster than. 

Very small Ni2Al3 phases with much more NIAI3 nucleation in the melt than peritectic growth in very rapidly cooled alloys Leach very much faster than. 

Fusion/ alloy leaching (mixed oxides, Raney metals)... 

Catalyst (alloy) Leaching C omposition of solution catalyst (atomic %) Cu (m /hil) Activity (g-CHgOH/1-cat.h) Specific activity (mg-CHgOHMiZ u h)... 

Keywords de-alloying, leaching, Raney-Ni catalysts, Monte Carlo simulation. 

Alloy Leach Solution Temp. (K) Catalyst Label... 

Production. Indium is recovered from fumes, dusts, slags, residues, and alloys from zinc or lead—zinc smelting. The source material itself, a reduction bullion, flue dust, or electrolytic slime intermediate, is leached with sulfuric or hydrochloric acid, the solutions are concentrated, if necessary, and cmde indium is recovered as 99+% metal. This impure indium is then refined to 99.99%, 99.999%, 99.9999%, or higher grades by a variety of classical chemical and electrochemical processes. 

A.lkaline Solutions. The most important example of alkaline leach is the digestion of hydrated alumina from bauxite by a sodium hydroxide solution at 160-170°C, ie, the Bayer process (see Aluminumand aluminum alloys). 

A process has been developed to recover niobium from ferroniobium (30). The need for this process came about when Brazil would only export niobium in the form of ferroniobium. The process starts with a hydriding step, so as to be able to cmsh the alloy. Screening precedes a nitriding step, followed by an acid leach of the iron nitrides. This leaves the niobium nitride for further processing to the pure niobium metal. 

Dezincification is explained by two theories. The first is that the alloy dissolves, with a preferential redeposition of copper. The other proposes a selective leaching of the zinc, leaving the copper behind. There is evidence that both mechanisms may operate, depending on the specific environment. 

Li was leached from a sample as a fimction of depth into the sample, they mounted the sample in epoxy and measured the Li as a function of distance from the alloy s surface using a finely collimated He beam. To know when they were measuring in... 

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