Study On Regeneration Of Degradation Products In Working Solution For Production Of Hydrogen Peroxide By AO Process

Hydrogen peroxide is an important chemical product widely used for chemical,textile,paper,food,medicine,environmental protection and other areas.Currently,the main productive method of hydrogen peroxide is anthraquinone process.This method is the alkyl anthraquinone dissolved in an organic solvent,hydrogenation and oxidation of hydrogen peroxide production by alternating.The degradation of anthraquinone in the hydrogen peroxide has been a major factoraffecting production.This paper focuses on the process conditions and catalyst modification method of regenerate the degradation in the working solution.Taking the purchase of ?-Al₂O₃ as catalyst,the effects of operating conditions on the working solution regeneration were studied within this thesis,It was found that the regenerating temperature and the resident time were the two key factors for the working solution regeneration.Prolonging the reaction time and increaseing the reaction temperature,are advantageous for regeneration of degradation products.Under the temperature of 60?,after 3 hours reaction,4.1% degradation products can be transformed into active anthraquinone.MgO/?-Al₂O₃ catalysts were prepared by incipient wetness impregnation with magnesium nitrate aqueous solution and ?-Al₂O₃ as supports.The as-synthesized catalysts were characterized by XRD,TEM,TPD and BET.The results show that the position of characteristic diffraction peaks shifts to the low-angle direction,indicating the formation of MgAl₂O₄ phase.The addition of MgO into ?-Al₂O₃ supports induced the decrease in the acidity and increase in the basicity of catalysts.2-alkyl-5,6,7,8-tetrahydro-9,10-anthrahydroquinone?alkyl = ethyl and amly?,2-alkyl-9-anthrone and real working solution as a model reaction,to evaluate the catalyticactivity of MgO/ ?-Al₂O₃ catalysts.The results show that,the catalytic performance of MgO/ ?-Al₂O₃ is better than the unmodified ?-Al₂O₃,and increase with increasing the MgO loading mass in MgO/?-Al₂O₃ catalysts.When the loading amount of MgO reaches 30%,MgO/?-Al₂O₃ catalyst for 2-alkyl-5,6,7,8-tetrahydro-9,10-anthrahydroquinone transformation were increased by 231% and 137% respectively,compared with ?-Al₂O₃,the regeneration of 2-amly-9-anthrone were increased by 25%,the regeneration of degradation products in real anthraquinone working solution is increased by more than 54%.Na₂O/?-Al₂O₃ catalysts were prepared by incipient wetness impregnation with magnesium nitrate aqueous solution and ?-Al₂O₃ as supports.Then the Na₂O/?-Al₂O₃ catalysts were used in the regeneration reaction of amyl anthraquinone working solution,to evaluate the activity of the catalysts.The result show that H4 AAQ and AAN can be converted into AAQ in the presence of Na₂O/?-Al₂O₃ catalysts.The conversations of H4 AAQ and AAN increases with the increase of Na₂ O loading first and then reduces,and both of them reach the maximum value at the Na₂ O content of 15%,with the improvement of 157% and 29%,respectively,compared with ?-Al₂O₃.