Re: how does Calcium hypochlorite decompose in the presence of catalysts?

I am not familiar with the use of these catalysts for this reaction.  I am 
surprised that catalytic amounts of these would produce a precipitate.  
question:

What amount of the catalyst is used compared to the calcium hypochlorite?
How much precipitate is formed?
What is the pH of each reaction?
 

1. The color of the iron precipitate is typical of FeCl3 or Fe(OH)3, but 
again it should not precipitate accept at high concentration.

2. The black with CuSO4 is typical of CuS, which may form at low 
concentrations, but you state the sulfate is a catalyst, so there should 
be no sulfide.

3. The chlorine smell is probably just a pH shift to give off chlorine, 
which hypochlorite easily does.

This reaction can also be done with a nickel catalyst.  Since it is a 
catalyst, it is not part of the reaction.  If you are getting side 
reaction, I might guess that you may have a pH problem.  As real 
catalysts, the only reaction should be the decomposition of the 
hypochlorite.