Preparation And Metal Doping Of Uniform Mesoporous TiO₂ Microparticles And Their Applications In Wastewater Treatment

With the rapid development of industry,the problem of environmental pollution has become increasingly serious.Among water pollution,the surface water is particularly polluted,and the total volume of potable water decrease year by year.However,traditional water treatment processes are difficult to effectively remove heavy metal pollutants with low content and organic pollutants with high content.For the heavy metal pollution,adsorption method has a good prospect,and the choice of adsorbent determines the amount of energy consumed and the cost of final disposal.The ideal adsorbent requires to meet the characteristics of low cost,large adsorption capacity,fast adsorption rate,stable physicochemical properties,and easy regeneration.At present,porous TiO₂ material has the potential to become ideal heavy metal ion adsorbent.In particular,the titanium hydroxyl groups on the surface of the TiO₂ material can undergo electrostatic adsorption with heavy metal ion groups under specific conditions.Utilizing this characteristic enables the material to rapidly complete the adsorption and regeneration process when adsorbing heavy metal ions.This paper presents a rapid and continuous method for preparing TiO₂ based on the advantages of TiO₂ as an adsorbent reported in the literature and utilizes a novel microfluidic spray technology.By combination with the evaporation-induced self-assembly?EISA?method and optimizing the process parameters in the experiment,a uniform mesoporous TiO₂ microspheres was prepared,the typical particle size is about 40 ?m.This kind of material has excellent performance of Cr?VI?adsorption.A large amount of Cr?VI?in the simulated wastewater can be adsorbed quickly and this material as adsorbent has fine cycle performance Further experimental results.suggested that uniform size adsorbents with dozens of microns have significant advantages in the dynamic adsorption process and further satisfy the demand for industrialized adsorbents.Degradation is one of the most popular treatment methods for organic wastewater.The degradation efficiency of organics and the cost of the treatment process depend on the appropriate degradation technology and catalyst.While the difficulty in the degradation of organic matter lies in whether it can be completely mineralized.Currently,photocatalysis and advanced oxidation technology have attracted widespread attention due to their simple process,energy saving and environmental protection features.Among them,the coupling of Fenton's method,ozone advanced oxidation method and photocatalytic method can effectively improve the removal rate of organic substances.Metal-loaded TiO₂ materials,on the one hand,act as advanced oxidation catalysts to catalye the rate of production of active substances,and on the other hand act as photocatalysts to provide photoelectron pairs.The synergistic effect of the two can effectively improve the number of active sites in the degradation system or the production efficiency of active substances.Based on this idea,a series of metal doped uniform mesoporous TiO₂ microparticles were prepared while Fe,Mn,and Cu were selected as the load.Photocatalytically assisted fenton reaction and photocatalytically assisted ozone advanced oxidation were used as degradation methods.Organic substances such as dyes and phenol,etc.were selected as pollutants.By optimizing the parameters in the preparation process,the crystal structure of the sample is effectively regulated.It is found that the degradation performance of Fenton reaction can be greatly improved by the modification of metal doping,and the catalytic degradation performance of photo-assisted ozone catalytic degradation can be significantly improved.