Catalysts Prepared with Matured Compost Derived from Mechanical-Biological Treatment Plants for the Wet Peroxide Oxidation of Pollutants with Different Lipophilicity
The current work proposes a strategy for the valorization of compost obtained from
municipal solid waste, through its activation with H2SO4 and thermal treatment at 400–800 C to
produce low-cost catalysts for wet peroxide oxidation. All the developed materials were catalytically
active for the aqueous solution oxidation of 2-nitrophenol (C2-NP,0 = 0.5 g L1) and 4-nitrophenol
(C4-NP,0 = 5.0 g L1). In particular, using the catalysts prepared by thermal activation of the compost
(with and without subsequent treatment with H2SO4), complete removal of both model pollutants
was achieved after 24 h (at 50 C, initial pH 3, Ccat = 2.5 g L1, and employing a stoichiometric quantity
of H2O2 needed for the total mineralization of the pollutants). In a cyclohexane–water mixture
(simulating biphasic oily wastewater), 4-nitrophenol is also completely removed by the catalyst not
treated with H2SO4. In contrast, the removal of 2-nitrophenol decreased to 93% due to its higher
lipophilic character. Thus, this work demonstrates that active catalysts for wet peroxide oxidation
can be obtained by using as a precursor a matured compost derived from municipal solid waste.
