Study On The Catalytic Activity Of Nano-enzyme Of High Iron Attapulgite From Gansu Province

Attapulgite(ATP)is a kind of one-dimensional fibrous nano material existing in nature,which has high porosity,large specific surface area and other excellent properties,and is widely used in all walks of life.In the process of dyeing wastewater treatment,decolorization is very important.At present,decolorization method is an important content of dyeing wastewater treatment.In this paper,through the study of the unique properties of high-iron ATP in Linze of Gansu Province,a variety of mineralogical analyses were carried out,and the adsorption and degradation experiments of methylene blue(MB)were carried out.The factors influencing the adsorption and degradation effect of MB were discussed in detail,and the reaction mechanism was discussed.The main contents of this paper are as follows:(1)Physical and chemical characteristics of high-iron ATP in Linze.Through mineralogical characterization of high-iron ATP in Linze,the following results are obtained.X-ray diffraction(XRD)results show that attapulgite,illite,kaolinite,quartz and feldspar are the main minerals of Linze high iron ATP;The iron phase of attapulgite is analyzed,which contains magnetic iron,carbonate iron,silicate iron,sulfide iron,hematite,etc;The results of X-ray fluorescence spectrometry(XRF)show that the main elements in high-iron ATP of Linze are Si,Al,Fe,Mg,etc;The results of X-ray photoelectron spectroscopy(XPS)show that the main form of Fe in Linze high-iron ATP is compound.(2)Activated high-iron ATP adsorbed MB.After acid,alkali and high temperature activation,the adsorption capacity of ATP for MB was improved.When ATP was activated with 15%HCl solution,2 mol/L Na OH solution and 350?high temperature,the adsorption rate of MB was 89.62%,85.34%and 81.32%respectively.The adsorption equilibrium of MB can be reached by activating high iron ATP within 30min.(3)A attapulgite enzymatic catalytic system was constructed.In the system,the adsorption equilibrium was achieved first,and then MB was degraded.The results showed that when the concentration of H₂O₂ was 0.15 mol/L,the content of ATP was10 g/L,the temperature was 60?,and the p H was 2,the degradation rate could reach100%within 4 h.According to the kinetic fitting results,the degradation of MB by ATP accorded with the pseudo first order kinetic equation.At the end of the experiment,the MB degradation experiment was repeated.The experimental results show that the degradation rate of MB can still reach 78%after 6 cycles.(4)A photocatalytic degradation system of attapulgite was established.The adsorption equilibrium was achieved first,and then MB was degraded.The results showed that the conditions of MB degradation in 1 h were as follows:the amount of ATP was 10 g/L,the concentration of H₂O₂was 0.15 mol/L,the initial concentration of MB in the solution was 100 mg/L,and the initial p H value of the solution was 2.At the end of the experiment,the reusability of high iron ATP catalyst in photocatalytic system was discussed.The results showed that the degradation rate of MB could still reach 82%after six cycles.Finally,the mechanism of MB degradation catalyzed by high iron ATP was studied by free radical capture experiment.Hydroxyl played a leading role in the degradation process.