Physicochemical properties of pyrogenic carbonaceous product, biochar, syngenetically modified for its use in adsorption systems

Abstract

The growing demand for organic products in the market promotes their use in various fields. One such products is biochar (BC). It was found that for climate change mitigation, biochar production from lignocellulosic biomass has more potential rather than biomass combustion for energy generation. Among the innovative environmental applications, biochar has potential as an adsorbent for retaining contaminants in environmental engineering and agrotechnical systems. Artificial modification of biochar can improve its adsorption capacity; however, indirect or natural change of biochar composition (e.g., contaminated biomass) based on syngenetic elements provides prospects for new applications of biochar as well as decreases the modification costs. The types of feedstock were lignin and wood of birch and pine trees growing in the area of aerogenic contamination and in the soil contaminated with potentially toxic elements. The temperatures of pyrolysis were 450°C and 700°C. The residence times of pyrolysis were 1, 2, and 4 h. The aim of this article is to evaluate the influence of the methods of modifying biochar syngenetically on its adsorptive properties. In the course of the study, it was found that the feedstock chemical composition mainly determined the composition of the biochar produced (R=0.434–0.906). It was found that the cation exchange capacity (CEC) of biochar had correlation with Pb, Cr, Ni, and Cd concentrations in biochar.