Characterization and Surface Analysis of Commercially Available Biochars for Geoenvironmental Applications

摘要

Biochar is a solid byproduct generated during anaerobic biomass pyrolysis or gasification that has recently gained interest for both agricultural and environmental uses owing to its unique physical and chemical properties. These properties include high surface area and porosity, and ability to adsorb a variety of compounds, including nutrients, organic contaminants, and some gases. Physical and chemical properties of biochar are dictated by the feedstock and production conditions (i.e. pyrolysis temperature and conversion technology), which vary widely across commercial biochar producers. In this study, several commercially available biochars are characterized for key physical and chemical properties relevant to the common uses of biochars in environmental applications, specifically as an amendment to soil landfill covers for enhanced methane oxidation. SEM images of each biochar type were analyzed using Pore Crack Analysis Software (PCAS)~? in order to quantify differences in surface porosity and structure. Trends in these properties are related to feedstock and production method to aid in the proper selection of biochar for geoenvironmental applications. A high variability in chemical composition, surface properties, and pore structure among commercially available biochars was observed, highlighting the importance of pre-screening biochars prior to use in applications such as a landfill cover or soil amendment.