Two-step strategy for the comprehensive utilization of tobacco stem.

Tobacco stem (TS) is a by-product of tobacco industry, and the conventional landfill and incineration will lead to the release of nitrogen-containing compounds and cause a series of environmental and ecological problems. The removal of alkaloids in TS is a key step for the further utilization of TS. In this study, a two-step strategy including leaching treatment and pyrolysis has been reported to remove alkaloids. The results showed that the leaching treatment not only reduces the content of nitrogen-containing compounds effectively, but also removes some metal inorganic salts. The peak area of nicotine (C₁₀H₁₄N₂) decreased from 45.03 × 10⁶/mg to 4.31 × 10⁶/mg, and the number of free radicals increases. The biochar from L-TS has a lower degree of graphitization, looser structure, lower H/C ratio and oxygen-containing functional group content. With the increase of the pyrolysis temperature, the secondary reaction results in the decomposition of oxygen-containing macromolecules and aromatic compounds to form small molecules chemicals. [ABSTRACT FROM AUTHOR]