Mesoporous carbon derived from a biopolymer and a clay: preparation, characterization and application for an organochlorine pesticide adsorption

Abstract

The production of carbon-based materials is a field of intense scientific research due to the diversity of potential applications that this kind of material presents. In this paper, it is reported the synthesis of porous carbonaceous material (PCM) based on the pyrolysis at 850 °C of a composite made of Laponite (commercially available synthetic clay) and Cassava starch, followed by clay removal through acid digestion. The Laponite presence influenced the structural order and textural properties of the pyrolytic carbon formed. After pyrolysis and acid digestion of clay, it was obtained a material with a partial graphitic structure containing majorly sp^2 bounded carbon atoms, that has almost twice the specific surface area and up to 20 times more mesopore volume than the carbonaceous material obtained without the clay. The adsorbent potential of PCM was evaluated by adsorption of Dicamba, an organochlorine pesticide, from aqueous solutions. The PCM exhibits a high Dicamba removal efficiency, with a maximum adsorption capacity of 251.9 mg g^−1 related to a pseudo-second-order kinetic adsorption model with a strong pH dependence.