Metal oxide-cellulose nanocomposites for the removal of toxic metals and dyes from wastewater

Waste water remediation of toxic metals and dyes could be complex to achieve owing to several factors. Various techniques have been developed for the removal of these pollutants. However, the success of these water treatment techniques mainly depends on the choice of appropriate media. Most of the commercial and chemically synthesized materials for water treatment create additional hazards due to the leaching of toxic chemicals into the process water. Consequently, studies on the development of better materials which could achieve high efficiency without posing any health risk led to the exploration of non-toxic composite materials such as those composed of cellulose and metal oxides. The focus is on the choice of materials and the best methods that allows their combination in order to address the pollution caused by heavy metals and dyes. This review critically analyses or assess the use of cellulose incorporated with metal oxides in the removal of toxic metals and dyes from industrial effluent. The nanocomposites have been accepted as a technique that circumvents the problems associated with the use of only metal oxides in water purification. They provide a platform for an improvement in the hydrophobicity of the composite with concomitant efficiency in adsorption and photocatalysis. (C) 2020 Elsevier B.V. All rights reserved.