| The anthraquinone method is a commonly used method for preparing hydrogen peroxide.However,there are inevitable side reactions in the anthraquinone process,resulting in the production of a large amount of degradants that do not have the hydrogen peroxide production capacitys,it is very important to regenerate the working solution.The conventional working solution regeneration catalyst is mainly a sodium hydroxide impregnated alumina ball.it has disadvantages such as easy loss of active components,short service life and so on.Therefore,it has very important significance to study a new type of anthraquinone working solution regeneration catalyst for hydrogen peroxide production.In this paper,the solid base catalysts of MgO/?-Al2O3 was prepared by the physical mixing method and the impregnation method,and the performance was studied.The studied on the molding process of the physical kneading method showed that the crushing strength of the catalyst reached 60.85 N/granule after 12 hours of aging treatment.When the addition amount of the starch paste pore former is 6 wt%,the pore volume is 0.38 cm3·g-1,the specific surface area is 295.0 m2·g-1,and the crushing strength of the catalyst can reach 50.34 N/granule.Based on this,the effect of MgO loading on the pore structure of the catalyst,the surface alkalinity of the catalyst and the regeneration activity of the ruthenium degradation product was also investigated.The results show that when the MgO loading is 15 wt%,the pore volume is 0.32 cm3·g-1,the specific surface area is 287.5 m2·g-1,and the number of basic sites is the highest,and the effective anthraquinone increase is 7.60 g·L-1.The impregnated method is prepared by immersing the shaped alumina particles in the solution of Mg(NO3)2 to prepare a MgO/?-Al2O3 catalyst.The monolayer dispersion property,pore structure,surface basicity and ruthenium degradation activity were studied.The results show that the monolayer dispersion threshold is 9.87 wt%of MgO prepared by impregnation method on strip ?-Al2O3 particles,and the pore volume is 0.41 cm3·g-1 when the actual MgO loading is 9.35 wt%.It reached 227.6 m2·g-1,and the effective anthraquinone increase reached 7.53 g·L-1.In this paper,a new method for preparing a solid base catalyst for the regeneration of anthraquinone degradants is proposed by combining atomic economic reaction and in situ growth method.Precursor of MgAl-LDHs synthesized directly on the surface of activated alumina by atomic economic reaction using speedy dewatering alumina(P-Al2O3)and Mg(OH)2 as raw materials.Then the catalyst of MgAl-LDO/?-Al2O3 which can be obtained by one-step calcination after extrusion molding.This method can avoid the disadvantages of secondary burning in the dipping method and the traditional in-situ growth method.The effects of precursor reaction temperature and Mg(OH)2 dosage on catalyst Morphology characterization,surface basicity and pore structure,and regeneration properties of ruthenium degradation products were investigated.The results show that the pore volume is 0.49 cm3·g-1,the specific surface area is 293.9 m2·g-1,the number of basic sites is the most effective.and the effective anthraquinone increase reached when the reaction temperature is 120oC,the amount of Mg(OH)2 is 20 wt%.In this paper,MgO/?-Al2O3 solid base catalysts of anthraquinone degradant regenerated was prepared by physical kneading and impregnation.A new preparation method for anthraquinone degradation regenerated catalyst was invented.The effects of different preparation methods on the performance of various aspects of the catalyst were discussed.This thesis has important theoretical and practical significance for the research and application of anthraquinone regenerating catalysts. |
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