Method for producing oxidized lignins and system for producing oxidized lignins

A method for producing oxidized lignins, wherein the method comprises bringing into contact

• a component (i) comprising one or more lignins,
• a component (ii) comprising ammonia,
• a component (iii) comprising one or more oxidation agents comprising hydrogen peroxide, and
• a component (iv) comprising polyethylene glycol,
• mass ratios of lignin, ammonia, hydrogen peroxide and polyethylene glycol being such that an amount of ammonia is from 0.01 to 0.5 weight parts, an amount of hydrogen peroxide is from 0.025 to 1.0 weight parts, and an amount of polyethylene glycol is from 0.03 to 0.60 weight parts, all based on a dry weight of lignin;
• and allowing a mixing/oxidation to take place, whereby an oxidized mixture is produced, followed by an oxidation step, the oxidized mixture being allowed to continue to react for a dwell time of from 1 second to 10 hours.