Hydrochars as novel functionalized materials for heavy metals removal

Abstract

Untreated industrial effluent is causing alarming levels of water pollution in our modern world. Hydrochars, functional carbonaceous materials obtained during the hydrothermal carbonization of waste biomass, possess a great potential for use in industrial wastewater treatment. Their high reactivity and regenerative properties compensate its deficiency, which is reflected in a small specific surface area. In addition, these materials are amenable to additional functionalization and modification by various chemical treatments. Previous studies have demonstrated that incorporating metals onto the surface of hydrochar or treating it with hydrogen peroxide or alkalis can significantly enhance its adsorption capabilities. This paper provides a brief overview of using hydrochars from various sources as adsorbents for heavy metals. This review aims to assess the impact of material modification on its structural characteristics and sorption capacity.