Siberian Federal University

The work is devoted to the study of the chemical structure and sorption properties of lignin isolated from the stems of industrial cannabis (Cannabis sativa) in relation to the radionuclide uranium‑238. Lignin was obtained as a result of alkaline cooking of raw materials, followed by precipitation from black liquor. The structure of the biopolymer was studied by IR‑Fourier and 2D‑NMR spectroscopy. It was found that the studied lignin belongs to the guaiacyl‑syringyl‑p‑coumar type (GSH). A unique feature of its chemical structure was revealed: an abnormally low content of β-O-4-ether bonds (22.8 %) and the dominance of pinoresinol structures (β-β), the number of which reaches 62.2 %. The study of sorption capacity under in vitro conditions simulating the environment of the gastrointestinal tract (38 °C; pH 2, 6 and 8) showed that hemp lignin has a high primary adsorption of uranium-238 (about 90 %). The index of strong adsorption after two stages of desorption was 63.5 %, which makes it possible to consider this material as a promising basis for enterosorption preparations designed to remove radionuclides from the gastrointestinal tract of mammals