METHOD FOR SYNTHESIS OF CROSS-LINKED CARBOXYMETHYLATED LIGNIN-CARBOHYDRATE MATERIAL Russian patent published in 2011 - IPC C08B11/12 C08H8/00 

FIELD: chemistry.

SUBSTANCE: lignin-carbohydrate material (LCM) is treated with sodium hydroxide (NaOH) in molar ratio of OH groups of LCM: NaOH equal to 1:1 at temperature 60°C for 120 minutes. Sodium monochloroacetate is then added in molar ratio of OH-groups of the LCM: ClCH₂COONa equal to 1:0.5 and trichloroacetic acid (Cl₃CHCOOH) is added in molar ratio of OH groups of LCM: Cl₃CHCOOH equal to 1: (0.025-0.6). The reaction mixture is held for 60 minutes at 60°C. The obtained product is washed with ethanol which is acidified with mineral acid and dried in air. The obtained product is characterised by high content of carboxyl groups and viscosity of alkaline solutions.

EFFECT: obtained carboxymethyl ether can be used in different fields, for example, as a reagent for drilling oil and gas wells, for stabilising mortar in the construction industry, as chemical reagents during floatation and in mining and processing industry.

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