A large area of the Athabasca oil sands region in northern Alberta has been surface mined, and large volumes of process water produced from oil sands extraction and upgrading. To facilitate reclamation and remediation of this disturbed land and process water, novel reclamation materials need to be developed that are economical, can be made with readily available materials, and are efficient in removing contaminants. Biochar is one of those promising materials and can be used to remove contaminants from soil and water, rebuilding functional soils and returning water to the environment.
Biochar properties mainly depend on feedstock type and production conditions, including pyrolysis temperature and post activation treatment. To date, most studies have focused on efficiency of biochars produced under limited pyrolysis conditions and feedstock types on specific contaminant removal. Relationships among biochar properties, including contaminant removal capacity, feedstock types, and pyrolysis conditions need to be better understood if the optimum biochar for land and water reclamation and remediation is to be produced. Novel biochars that are effective for removal of multiple contaminants with high surface area and porosity and a variety of functional groups need to be developed through surface modification, including surface functional groups, charge, and pH modification, following biochar production.
Ideally the modified biochar should be used for process water remediation, then for land reclamation, rather than being landfilled. The impact of used biochar application on soil properties, plant growth, and greenhouse gas emission needs to be evaluated. Potential to desorb contaminants also needs to be addressed.