Study On Preparation Of High Pure Hydrogen Peroxide By Combination Of Chelation And Ion Exchange

High purity hydrogen peroxide is widely used in the fields of electronics industries.The technologies of producing high purity hydrogen peroxide are more and more focused.The ion exchange resin method for high purity hydrogen peroxide production has the advantages of moderate conditions and high purity of product,but the researches on theoretical foundation of ion exchange process for purifying hydrogen peroxide are very few,many problems are urgently to be solved.Study on the purifying of technical grade hydrogen peroxide by ion exchange resins will have a theoretical and practical significance.Through the screening from different types of the ion exchange resins,and researching on fundamental experiments of ion exchange resins and chelate resins,the shortcomings of traditional purification processes were overcome by integration technology,which was comprised of the adsorption,chelation,ion exchange and membrane separation.This thesis mainly includes several aspects:1.Through exploring pretreatment conditions,their optimal values for raw hydrogen peroxide solution and ion exchange resins were determined.2.By comparing vapor volumes generated from purifying hydrogen peroxide solutions with 12 types of ion exchange resins,analyzing the structure changes of 12 types of ion exchange resins immersed in hydrogen peroxide solutions and high pure water,and observing the DFS(Decontamination Factors) values of all kinds of ion exchange resins for purifying hydrogen peroxide solutions,to determine the 1200Na and IRA900 chosen from 12 types of ion exchange resins.3.By the static state method,to draw the equilibrium isotherms of single ion solution and multicomponent solution under different temperatures.By the use of Langmuir model, Freundlich model and Markham Benton model,to fit the experiment data and evaluate the thermodynamic parameters.The results showed that purification of hydrogen peroxide solution was exothermic and adsorption was not suitable to purify a single ion solution under the increasing temperature conditions.Langmuir model,Freundlich model provided a better fit to the experimental data,but multicomponent solution was unsuitable to Langmuir model, Freundlich model,and even Markham Benton model.4.The mechanism of particle diffusion control for ion exchange process was determined by indirect judgment method.Kinetic equations of ion exchange were developed according to the two-phase diffusion model,and kinetic data were predicted for single ion and multicomponent solutions.The results showed that the experimental curves agree well with predicted ones of single ion solution,except multicomponent solution.5.The experimental results of purifying hydrogen peroxide by chelating resin under different conditions indicate that D401 is effective resin to purify trace metal ions such as Ca, Fe,Zn and Al,but it is not effective for K and Na ions in pretreatment stage.Before purifying technical grade hydrogen peroxide,D401 is used to pretreat technical grade hydrogen peroxide to reduce the accumulation of ions on ion exchange resins such as Ca,Fe,Zn and Al, and enhance the stability of ion exchange process.Through the study,to learn the purifying effects of D401 in the removal of Ca,Fe and Zn from aqueous solution under different experimental conditions such as pH,resin dosage,contact time and contact temperature.The experimental results and the observations show that resin dosage and contact time are main factors and pH and contact temperature are minor factors,it is not suitable when the purifying temperature is higher than 35℃,and neither is it when the pH value is higher than 5.6.The study on dynamic state performances of ion exchange for purifying hydrogen peroxide solution including Na⁺,PO₄^3-individually show that the ion concentration,velocity, ratio of height to diameter have effected on waves shape,breakthrough width,breakthrough volume,and it provides the basis for determining of the suitable operating conditions of ion exchange column.The breakthrough curves was analyzed and simulated by the constant-pattern wave model.The results show that the constant-pattern wave model is suitable to cation exchange column.Based on experimental data,the general correlations of dynamic column process for hydrogen peroxide solution are presented and correlation parameters are determined.It indicates that the correlations are suitable to the experimental data of ion exchange column process.7.Combining with experimental results,the integration technology of the adsorption, chelation,ion exchange and membrane separation has been applied to the design of purification process of 200 tonnes per annum.The product quality has achieved and exceeded the standard of SEMI-C7.The products have been used in the fields of electronics industries.