My hypothesis is that the aluminum in the chemalloy is being consumed by the NaOH to give off hydrogen gas much the same way "raney nickle" is made only much slower.
from wikipedia:
Raney nickel is a solid catalyst composed of fine grains of a nickel-aluminium alloy, used in many industrial processes. It was developed in 1926 by American engineer Murray Raney[1] as an alternative catalyst for the hydrogenation of vegetable oils in industrial processes. More recently it is used as a heterogeneous catalyst in a variety of organic syntheses, most commonly for hydrogenation reactions.
Raney nickel is produced when a block of nickel-aluminium alloy is treated with concentrated sodium hydroxide. This treatment, called "activation", dissolves most of the aluminium out of the alloy. The porous structure left behind has a large surface area, which gives high catalytic activity. A typical catalyst is around 85-percent nickel by mass, corresponding to about two atoms of nickel for every atom of aluminium. The aluminium which remains helps to preserve the pore structure of the overall catalyst.Statistics: Posted by sparkgap — Tue Jan 20, 2009 1:58 pm
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