Recyclable Cu-based monolith catalysts for peroxymonosulfate-activated degradation of organic dyes

The development of monolith catalysts with high reusability for the advanced oxidation processes targeting water-pollution remains a big challenge. In this work, we prepared a series of Cu-based monolith catalysts by simply calcining metallic Cu foam or Cu sheet under different temperatures. Performance of the monolith catalysts was evaluated in degradation of Methylene Blue or Orange II with peroxymonosulfate as oxidant. The monolith catalyst is more efficient at higher pH of the reaction medium, and can be used at least 20 cycles without loss of the degradation activity. Based on the characterizations of XRD, XPS and EPR, the active composition of the catalysts for the degradation is ascribed to CuO, and the active radicals generated during the degradation process are speculated to be O2•–, ·OH, SO4•– and 1O2.