Copper (sorbed on chitosan flakes) was used
as a catalyst for the oxidation of hydroquinone, with dioxygen
(from air) and hydrogen peroxide as oxidizing agents.
The supported catalyst was very efficient at oxidizing hydroquinone
into p-benzoquinone. With hydrogen peroxide
at pH 5.8, drastic oxidizing conditions led to the formation
of sub products. With a short contact time, together with the
use of a low hydrogen peroxide concentration and a small
amount of the catalyst, the formation of subproducts could be minimized. The influence of the catalyst/substrate and
hydrogen peroxide/substrate ratios was investigated to determine
optimum experimental conditions for a high initial
oxidation rate and a high production of p-benzoquinone.