ABSTRACT
Environmental pollution, causing serious harmful concerns, is increasing day by day. Various chemical and biological remediation strategies are being adopted to mitigate pollution. Out of those remediation strategies, biochar is one of the most investigated topics since the last decade. Biochar is a carbon derivative obtained from the carbonization of various organic biomasses under limited supply of or without oxygen, which yields a porous, carbon rich material with low density. Biochars have several physicochemical properties of interest such as high specific surface area and cation exchange abilities that are strongly affected by the source materials and pyrolysis temperatures, which enhance the sorption of a variety of contaminants to their surfaces. The sorption of these contaminants occurs through various processes, namely, ion exchange, electrostatic interaction, complex formation, membrane filtration, physisorption, and precipitation. 124To increase the pollutant removal capacity, further modification of the biochars may also be done by adding some metals like iron, calcium, magnesium, sulfur, silver, zinc, etc., through acid treatment, with the help of clay particles. Such modifications increase the surface area, affect the polarity, alter the pH, and form new functional groups in biochar which increases the adsorption capacity. In this chapter, we will be discussing about the production methods of biochars and various biochar composites, properties, and their utilization for remediation of environmental pollution.
