Exploring the Role of Carbon Nanosheets for Detoxification of Cr(VI) from Aqueous Solution

Abstract

Toxic pollutants in wastewater must be reduced in order to protect the aquatic ecosystem's stability and the public's health. Finding affordable and effective technologies for treating municipal, horticultural, aquacultural and industrial wastewater is urgently needed. Nitrogen-doped carbon nanosheets (N-CNS), which are produced by hydrothermal reaction from glycerol, sulfuric acid and melamine, have strong adsorptive behaviour against hazardous aqueous pollutants such as heavy metals and organic compounds. The overall elemental composition of CNS is altered by nitrogen incorporation, favouring CNS interaction with pollutants. The objective of the current investigation was to investigate the possibility for Chromium(VI) [Cr(VI)] adsorption on the CNS from a liquid solution. The ideal pH for Cr (VI) adsorption was noted to be 2.0. The Cr(VI) adsorption was enhanced when the starting metal concentration is more up to 700 mg L-1. A maximum removal of 256.41 mg g-1was seen when pH was 2.0 at 700 mg L-1 initial Cr(VI) concentration. We employed both the Freundlich and the Langmuir adsorption isotherms to determine the adsorption equilibrium constants. Using fitting curves and correlation coefficients (R2), it has been found that the model of the Langmuir isotherm is a best fit and it indicates homogeneous surface of CNS.