Green Oxidation of Carbon Black by Dry Ball Milling

A sustainable and green method is presented in this paper to produce highly oxidized carbon black using dry ball milling. The mechanical energy by colliding milling balls is able to easily break and build chemical bonds providing new oxygenated functional groups. The reaction is performed in the presence of air and in solvent-free conditions achieving, for the first time, a high degree of functionalization comparable to that obtained under harsh conventional conditions. With different milling times, it is possible to control the degree of oxidation. The procedure is environmentally friendly, respecting important green metrics, no solvent or additional reagent is required, and the product can be collected without any assistance from a solvent.