COMPOSITION OF WOOD PRESERVATIVE BASED ON MODIFIED LIGNIN Russian patent published in 2024 - IPC A01N59/14 A01N59/16 A01N59/20 A01N61/00 B27K3/15 B27K3/16 B27K3/22 B27K3/26 A01P3/00 

FIELD: wood processing.

SUBSTANCE: invention relates to means and materials for wood processing. The method of producing a wood preservative composition involves the stages of: a) mixing lignin and a solution of Na₂B₄O₇ or NaNO₃ with stirring; b) adding, with stirring, a metal salt containing an M²⁺ ion, wherein M is selected from chromium (II), copper (II), zinc (II) and cadmium (II); c) filtering the solid obtained in step b), which is modified lignin; d) suspending the modified lignin in water to obtain a wood preservative composition, the final concentration of the modified lignin in the wood preservative composition being from 0.1 to 30% by weight. Preferably, a base selected from NaOH and KOH is added to obtain a pH of 7 to 13, and an acid selected from boric acid, acetic acid, sulfuric acid and hydrochloric acid is added to obtain a pH of about 7. The metal salt anion is NO₃^2-. The wood preservative composition contains the following: 0.1–30 wt.% relative to the total weight of the modified lignin preservative composition obtained in steps a), b) and c) of the method, a base selected from NaOH and KOH, and an acid selected from boric acid, acetic acid, sulfuric acid and hydrochloric acid to obtain pH about 7; and the rest is water. The wood preservative composition is used in a method of preserving wood used outdoors.

EFFECT: proposed wood preservative prevents wood decomposition due to wood-feeding fungal agents, provides hygroscopicity and fire resistance.

8 cl, 3 tbl, 10 dwg, 13 ex