Patent ID: 7238335

Claim:
A process for the preparation of hydrogen peroxide by the anthraquinone cyclic process using a working solution containing as reactant at least one alkyl anthraquinone and/or alkyl tetrahydroanthraquinone, comprising the following steps: a) catalytically hydrogenating said working solution; b) oxidizing the hydrogenated working solution obtained in step a) with an oxygen-containing gas; c) performing an aqueous extraction of the hydrogen peroxide from the oxidized working solution obtained in step b) d) returning the extracted working solution obtained in step c) to step a) in a recycle stream; e) either periodically or continuously performing a regeneration step, comprising: i) contacting the hydrogenated working solution of step a) or the oxidized extracted working solution of step c) with an aqueous regenerating solution, L1, containing at least one alkyl anthrahydroquinone and/or alkyl tetrahydroanthrahydroquinone in deprotonated form to produce an L1/working solution mixture; ii) separating the L1/working solution mixture of step i) into a working solution phase, P 1 , and an aqueous phase, P2; and iii) returning the working solution phase P 1 to the anthraquinone cyclic process.