Oxidation of hydroquinone to p‐benzoquinone catalyzed by Cu(II) supported on chitosan flakes

Abstract 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 subproducts. 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. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3034–3043, 2006