Carbon nanotube based magnetic composites for decontamination of organic chemical pollutants in water: A review

Abstract

Contamination of water by organic chemical pollutants is one of the most critical environmental problems today as these are harmful to human beings and the aquatic ecosystem. Organic chemical pollutants persist for a long time in water and cause deleterious effects on human health even in small concentrations. Hence, decontamination of water demands simple methods using efficient materials. Carbon nanotube (CNT) based composites with metal/metal oxide have been materials of significant interest for decontamination of organic chemical pollutants from water due to their catalytic, magnetic, and structural features. Most of the adsorbents/catalysts pass through the challenge of separation from solution, and incorporation of magnetism can make them easily separable in presence of an external magnet. In this review, we present recent progresses and prospects in carbon nanotube based magnetic composites as potential decontaminants. We (i) identify the types of CNT based magnetic composites, (ii) evaluate the magnetism in the composite, (iii) identify different types of organic chemical pollutants in water decontaminated by CNT based magnetic composites, (iv) study the mechanism of removal of pollutants by the composite, (v) assess various parameters such as, nature & composition of CNTs, surface area, pore size & pore volume of the composite, pH of the medium, concentration of the pollutant, nature of the pollutant, temperature and contact time, those affect the efficiency of the composite. A comprehensive analysis on the interaction of organic pollutants and the composite, which play a pivotal role in decontamination of water, has been presented. The removal of organic pollutants like dyes, pharmaceuticals, pesticides, aromatic hydrocarbons and persistent organic pollutants from water has been covered. Overall, this review provides insight for the future efforts on CNT based magnetic composites for the decontamination of organic chemical pollutants in water.