Reactivity of the intermediates of the reduction of SO2. Functionalization of graphite, graphite oxide and graphene oxide

Abstract

Graphite particles (0.505-‰mm) were oxidized to graphite oxide with KClO3 in a H2SO4/HNO3 mixture. Graphite and graphite oxide particles were modified by reaction with SO2 at 630-‰°C. Thiolysis with sodium dodecane-1-thiolate and aminolysis with dodecane-1-amine of these particles occurred with the insertion of the organic moiety in the carbon matrix. Graphite microparticles (6.20-‰μm) were oxidized by H2SO4/ KMnO 4/ H2O2 mixture and were exfoliated to graphene oxide sheets (MPGO). MPGO was modified by reaction with SO2 at 630-‰°C. The modified MPGO was refluxed in DMSO with dodecane-1-thiol, dodecane-1-amine, and hexadecane-1-bromide. The reactions occurred with the insertion of the organic moiety in the carbon matrix, according to the X-ray photoelectron and nuclear magnetic resonance spectra. Mechanisms for the reactions were postulated using the atom inventory technique. Despite the structural differences, graphite, graphite oxide, and graphene oxide present the same selectivity for aminolysis and thiolysis reactions, with respect to the oxidized and non-oxidized intermediates of the reduction of SO2, as was found for the activated carbon. © 2014 John Wiley & Sons, Ltd.