Microwave synthesis of biochar for environmental applications

摘要

Growing environmental awareness attracted research attention to the development of efficient methods in the recycling and the recovery of wastes. Microwave assisted pyrolysis (MWAP) is an alternative heating approach to convert organic waste materials into value-added products, such as biochar (BC), biogas and bio-oil. Different types of biochar materials have been produced through microwave heating technique that, in most of the cases, can be utilized for adsorption of organic and inorganic pollutants. The BC have been employed as CO2 mitigator and fertilizer for soils due to their promising physiochemical properties. In this review paper, we discuss the various aspects of Microwave assisted pyrolysis and the available case studies, as well as the mechanism of adsorption of different pollutants onto biochars. Development of microwaved biochar for other applications such as supercapacitors, batteries, electrode materials, and composite membranes are also discussed. It is believed that the development and synthesis of high potential biochar through microwave assisted pyrolysis still needs very precise adjustment of processing conditions, pre-treatment of feedstock and post treatment steps for further enhancement of properties for specific applications. The paper concludes that considering the sustainable route in development of high-performance biochar would make microwave assisted pyrolysis cost-effective, environmentally friendly, and tunable materials of great potential for wide range of applications.