METHOD OF SULPHATING ORGANOSOLVENT LIGNIN Russian patent published in 2019 - IPC C08H7/00 C07G1/00 

FIELD: chemistry.

SUBSTANCE: invention relates to chemical technology and is intended for preparation of water-soluble ammonium or sodium salts of lignin sulphate esters, which can be used as chemical additives to regulate the properties of washing liquids when drilling oil and gas wells, and in the pharmaceutical industry as potential antiviral drugs. Method of sulphating organosolvent lignins is carried out by reacting lignins with sulfating complex sulfamic acid – urea while stirring in homogeneous medium in presence of diethylene glycol dimethyl ether solvent at temperature of 80–120 °C for 3.0–5.0 hours at a ratio of the amount of lignin to the sulphatation complex equal to 1:3 (g:mmol). Product is isolated by diluting with water, neutralization and purification from low-molecular impurities by dialysis.

EFFECT: high output of sulphated lignin, wider range of solvents for lignin sulphation in a homogeneous medium.

1 cl, 1 tbl, 7 ex