Not sure about the exact equations. But I think the purpose of those ingredients is to produce O2 to speed up the rust process. Except, I think the CuCl2 may just be for color.
You could experiment with your own solutions. Acids in general (even vinegar) will speed up the oxidation.
Hydrogen Peroxide and Bleach will produce O2 gas, which may work too. (But I've never tried that one. Stick to store-bought low concentrations.)
I don't know if it works on metal, but Potassium permanganate will create an aged look on wood, cloth, and glass.