Materials for Energy, Efficiency and Sustainability: TechConnect Briefs 2015Materials for Energy, Efficiency and Sustainability TechConnect Briefs 2015

Water Technologies Chapter 8

Nitrogen-doped porous carbon for the removal of Cr or As in aqueous solutions

J.S. Han, D.G. Ha, S.H. Kang
Seoul National University, Korea

pp. 275 - 278

Keywords: chromium, asenic, PH, nitrogen, pore distribution

The removal of hexavalent chromium and arsenic from aqueous solutions was investigated with nitrogen-doped porous carbon. Excellent adsorption behavior was obtained due to the strong attraction between [HCrO4]- or [H2AsO4]- and nitrogen sites under weak acidic conditions. It is because nitrogen atoms adjacent to carbon are positive in charge. Furthermore, nitrogen has an important role in producing various size of pores in carbon: from micro to meso when synthesized via chlorination of Ti(CxN1-x). In this paper, we study the influence of different pH, specific pore size, functional nitrogen, and defect degrees on the adsorption of Cr or As. Superior Cr adsorption to As by nitrogen-doped carbon was interpreted by comparing the binding energy of [HCrO4]-, [H2AsO4]-, and [OH]- with various nitrogen sites. Overall, nitrogen-doped porous carbon with micro pores can remove Cr and As from aqueous solutions.