Abstract
Biochar is a stable form of carbon produced via the pyrolysis of biomass for use in sustainable environmental and agricultural practices. The concept of biochar was originally triggered from the ancient practice in which humans deliberately mixed carbonized biomass into soils to enrich the soil quality and fertility. According to the International Biochar Initiative (IBI), biochar can be defined as “a solid material obtained from the thermochemical conversion of biomass in an oxygen-limited environment.” Biomass-derived biochar production has been demonstrated as a potentially viable strategy for developing negative carbon emission technologies for climate change mitigation and as a material for effective amendment of relatively poor agricultural soils. Most interestingly, ongoing biochar research work has expanded broadly, stretching from its traditional core in the environmental and agricultural science to studies in the use of biochar for energy generation and as adsorbents for pollution treatment applications. The use of biochar for carbon sequestration and soil amendment has also attracted more interests by research scientists globally. Application of biochar as a material for soil amendment is closely linked with its potential for climate change mitigation by carbon sequestration. Specifically, the properties of biochar include resistance to microbial degradation and chemical transformations, high surface areas, high water retention capacity, cation-exchange capacity, porosity, and its effectiveness as support and substrate for soil microbes. These characteristics endow biochar with a greater potential to become a highly useful material for improving agricultural productivity through soil quality enhancement while simultaneously sequestering CO2 from the atmosphere to mitigate climate change. Although activated carbon is the most popular and widely used adsorbent for organic pollutants, several studies have proven that biochars derived from biomaterials are effective in the removal of a variety of pollutants, including a group of emerging environmental pollutants called perfluoroalkyl and polyfluoroalkyl substances (PFAS). These harmful synthetic contaminants are widely distributed in the environment and are known as “forever chemicals” due to their persistent nature. Moreover, biochar ability to absorb electromagnetic radiation and emit far-infrared wavelength radiation has promoted research, development, and commercialization of biochar’s applications in medical and health therapies.