The extraction process for preparing hydrogen peroxide with bottom air injection in a spray column was investigated. With the increase of air superficial velocity

extraction efficiency was improved remarkably and the height of transfer unit (HTU) was largely reduced. Extraction efficiency was 2—3 times higher than that of liquid-liquid extraction without air introduction

and the HTU was only 1/2—1/3 of liquid-liquid extraction. Moreover

the air-liquid-liquid reactive extraction system for preparing hydrogen peroxide via anthraquinone was investigated. Oxidation reaction of the hydrogenated working solution was combined with extracting hydrogen peroxide from the working solution in a sieve plate column

which involves simultaneous oxidation of 2-ethylhydroanthraquionone and liquid-liquid separation. Oxygen was introduced with the hydrogenated working solution through a nozzle on the bottom of the column

with oxygen working as an agitating source as well as a reagent. Reaction rate and extraction efficiency increased with increasing air injection superficial velocity because of great improvement of mass transfer between air-liquid-liquid phases.