Method and system for preparing hydrogen peroxide

A method for producing hydrogen peroxide, comprising:

• operation 1) feeding a working solution containing an alkylanthraquinone to a hydrogenation reactor and subjecting the alkylanthraquinone to a hydrogenation reaction in the presence of hydrogenation catalyst particles and hydrogen to obtain a slurry comprising a hydrogenated anthraquinone, a by-product and the hydrogenation catalyst particles, recovering the hydrogenation catalyst particles from the slurry to obtain a circulating slurry rich in hydrogenation catalyst particles and a hydrogenated solution free of hydrogenation catalyst particles, and returning the circulating slurry to the hydrogenation reactor;
• operation 2) dividing the hydrogenated solution into two streams, and regenerating the first stream of the hydrogenated solution to convert at least a part of the by-product contained in the first stream of the hydrogenated solution into the alkylanthraquinone to obtain a regenerated hydrogenated solution;
• operation 3) contacting the second stream of the hydrogenated solution and the regenerated hydrogenated solution with an oxygen-containing gas for an oxidation reaction to obtain an oxidized solution containing hydrogen peroxide and the alkylanthraquinone;
• and
• operation 4) carrying out extraction separation on the oxidized solution to obtain an extract liquor containing hydrogen peroxide and a raffinate containing the alkylanthraquinone, and returning the raffinate to the hydrogenation reactor for use as a part of the working solution;
• wherein the ratio of the volume flow rate of the circulating slurry to that of the working solution is 6-20:1, and the ratio of the mass flow rate of the first stream of the hydrogenated solution to that of the second stream of the hydrogenated solution is 10-50:50-90.