Recent advances in hydrochar application for the adsorptive removal of wastewater pollutants

Water pollution is one of the major environmental challenges in contemporary times. Biochar from hydrothermal processes (known as hydrochars) has been explored as adsorbents for the removal of pollutants from wastewater. Hydrochars are a special class of biochar that is obtained from hydrothermal processes such as hydrothermal carbonisation (HTC) and hydrothermal liquefaction (HTL). Because of its good pore volume, surface area, high efficiency, and regeneration ability, hydrochar is an appealing choice for the remediation of a wide range of contaminants. This review aimed to focus the uniqueness of hydrochar properties and evaluate their performance on the adsorption of different pollutants from wastewater. It was observed that hydrochars can be effectively applied to a wide variety of pollutants including heavy metals, dyes, Pharmaceutically Active Compounds (PhACs), Endocrine Disruption Chemicals (EDCs), nitrates, phosphates and sulphate. The utilisation of hydrochar in water treatment solves constraints such as lack of regeneration, environmental friendliness, commercial feasibility, and disposal, handling or management concerns.