Preparation Of Nickel Ferrite Complex With Natural Ore And Microwave Catalytic Degradation Of Organic Pollutants In Aqueous Solution

In recent years,more and more research on microwave?MW?application of catalytic technology in water pollution control.As to ferrite microwave catalytic oxidation catalyst technology is the research hotspot in recent years,has become a new effective method for the treatment of organic wastewater.However,in the microwave catalytic degradation of nickel ferrite,there are many problems,such as high cost and uneven dispersion of "hot spots".In order to reduce the cost and disperse the "hot spot" in the surface of the nickel ferrite under microwave irradiation,the NiFe₂O₄ was modified in this study,and the natural organic compound was used as the carrier to degrade the organic pollutants in the water by NiFe₂O₄ composite natural ore.Microwave hydrothermal method was introduced to prepare Ni Fe₂O₄/sepiolite,NiFe₂O₄/diatomite and NiFe₂O₄/kaolinite catalyst.To characterize these three kinds of catalysts,SEM catalyst,XRD and FTIR were tested and compared the difference of three kinds of catalyst particle size.The catalytic activity of NiFe₂O₄/sepiolite,NiFe₂O₄/diatomite,and Ni Fe₂O₄/kaolinite were compared.Therefore,the order of activity of the three NiFe₂O₄/natural ore is as follows: NiFe₂O₄/sepiolite >NiFe₂O₄/diatomite > Ni Fe₂O₄/kaolinite.Moreover,microwave hydrothermal pressure and time,molar ratios of NiFe₂O₄ and natural ore,and pH value of precursors,effects of microwave irradiation time,used time on organic pollutants for the degradation efficiency were studied.Mole ratio of 9:1,1.5 MPa,30 min,3.2 g/L catalysts,25 mL,10 mg/L methyl parathion?MP?,750 W,and 5.0 min microwave irradiation time were used,and the degradation rate is 100 %.In addition,azo fuchsin?AF?was used as the target pollutant and the degradation time was 3.0 min,the solution could be completely removed.However,the results show that organic pollutants such as methyl parathion?MP?,sodium dodecyl benzene sulfonate?SDBS?,crystal violet?CVL?,and azo fuchsine?AF?in aqueous solutions could be degraded effectively and rapidly in NiFe₂O₄/sepiolite/MW system.The degradation rate constants?k?of CVL,MP,AF and SDBS in NiFe₂O₄/ natural ore /MW system were calculated to be 1.864,0.782,0.472 and 0.329 min-1,respectively.In conclusion,the microwave catalytic degradation technology using NiFe₂O₄/natural ore catalyst shows great potential in organic wastewater treatment.