Sustainable manufacture and application of biochar to improve soil properties and remediate soil contaminated with organic impurities: a systematic review

Biochar production and application have become increasingly popular in the past 15 years. Biochar, derived from diverse biomass types, offers a rich carbon source created through thermal combustion. Biochar production primarily depends on pyrolysis conditions and feedstock type. This review focuses on the multifaceted aspects of biochar, encompassing hydrothermal carbonization, gasification, and pyrolysis temperatures in biochar production and its role in bioeconomy and soil remediation. Biochar has yielded valuable insights, notably in decreasing nutrient leaching, curbing greenhouse gas (GHG) emissions, reducing the bioavailability of environmental pollutants, sequestering carbon (C) in soils, and enhancing agricultural productivity. Consequently, it has emerged as a valuable commodity for the bioeconomy, which involves harnessing bioresources through bioengineering to create economically valuable products. As a marketable output, biochar finds application in energy, diverse biochar-based product manufacturing, and the agricultural sector. Thus, biochar production not only enhances soil quality but also unlocks additional revenue streams. This review underscores the critical role of feedstock selection and pyrolysis conditions in optimizing biochar production. Furthermore, it highlights biochar as a sustainable and effective tool for improving various soil types and remediating soil contamination caused by organic impurities, including persistent organic compounds and antibiotics.