| The problem of arsenic pollution in water has seriously threatened regional ecological security.The development of new and efficient arsenic adsorption materials is a frontier topic in international research.The adsorption and removal of As（III）in water is a difficult problem in the development of arsenic adsorbents.Due to its photocatalytic activity,nano-titanium dioxide has become one of the most promising new materials for arsenic adsorption.The subject proposes the use of TiO 2-X materials with oxygen deficiency for the photocatalytic oxidation and adsorption of As（III）ions in water,and proposes a method for rapidly p reparing nano-TiO2-X with metatitanic acid as raw material.This paper focuses on the academic ideas put forward by the subject,comparative study of static hydrogen reduction method,high temperature plasma method,rapid hydrogenation reduction method for the preparation of TiO2-X,and the sample were characterized by XRD,TEM,UV-Vis DRS,BET,FTIR,XPS,powder resistivity test.The physicochemical properties of TiO2-X powders prepared by different methods were investigated and the effects of temperature,atmosphere and other factors on the physicochemical properties of sample color,during the preparation process,on phase,microstructure and light absorption properties were investigated.The results show that the static hydrogen reduction method could prepare TiO2-X-X powder,but the time period is long,and th e product is agglomerated and not suitable as an adsorbent.The product prepared by high temperature plasma method has a short time（about 1 s）,and the specific surface area of the obtained product is larger than that of the static method.However,the product phase mainly consists of Magnéli phase Tin O2n-1（3<n<10）,which has been converted into low-priced titanium oxide.The rapid hydrogenation reduction method produces TiO2-X in about 10 seconds,and the rutile-type meta-titanic acid and anatase-type meta-titanic acid are used as raw materials in a hydrogen atmosphere at 600℃,respectively,and the phase of the obtained sample is still a titanium dioxide phase.The specific surface areas are 108m2/g,210m2/g,the particle size is 10-20nm,and the forbidden band width is reduced by 0.05-0.06eV,which is suitable as an arsenic adsorbent compared to the raw material with high visible light absorption capacity.Comprehensive comparison,the final two sets of samples prepared in a hydrogen atmosphere at 600℃for subsequent arsenic adsorption experiments.By the self-built arsenic adsorption capacity test platform,the effects of sample crystal form,solution pH,illumination and initial concentration on the adsorption characteristics of Asn+in TiO2-X samples were investigated by ICP-MS and XPS.The adsorption results show that the arsenic adsorption kinetics of TiO2-x accords with the quasi-second-order kinetic equation based on chemical adsorption,and the equilibrium time is4h.Under the condition of no light,As（V）in water can be better adsorbed and removed under the acidic condition of pH=3,and As（III）can be better adsorbed and removed under the alkaline condition of pH=8.In the acidic environment under visible light,the arsenic（III）adsorption and removal ability of the sample is improved,but suppressed in the alkaline environment.Subsequent initial concentration experiments and XPS tests proved that TiO2-x has strong photocatalytic activity.Under visible light irradiation,arsenic（III）can be oxidized to As（V）,and the photocatalytic oxidation of arsenic（III）of anatase TiO2-X to arsenic（V）was calculated to be 111.3mgAsg-1h-1.Studies have shown that the rapid hydrogen reduction method is more suitable for the preparation of TiO2-X than the other two methods.The prepared sample exhibits good photocatalytic oxidatio n adsorption of arsenic（III）under visible light conditions.In this paper,a new method for rapid preparation of TiO2-X is proposed,and the product is applied to the field of visible-light photocatalytic arsenic adsorption,which expands the application field of TiO2-X,and provides reference for the rapid preparation and application of TiO2-X. |
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