Preparation Of Carbon Adsorped Rare Earth Ferrite Powder And Their Photocatalytic Degradation Of Pollutants In Water

Due to the world’s economic and military needs,the use of fuel is increasing.The use of fossil fuels has caused a large number of pollution problems,among which the treatment of industrial wastewater is particularly important.Among all kinds of sewage treatment technologies,photocatalytic technology has been applied in the field of sewage treatment because of the characteristics of mild reaction conditions,simple operation,green and efficient.The selection of catalyst materials in photocatalytic technology is very important,semiconductor generally has high stability,is the most applied and studied materials in photocatalyst.Ti O₂is the most widely studied in this field.Ti O₂is stable,cheap and readily available,and has a high photocatalytic rate,but it has a high electron hole recombination rate,leading to no light response phenomenon in the range of visible light.This important and fatal shortcoming restricts the catalytic use of Ti O₂.Therefore,a large number of research points in the field of photocatalysis are looking for new semiconductor photocatalysis materials that are more stable,cheap and have a wider range of light response.Based on this,the main contents of this paper are as follows:（1）Using Eu（NO₃）₃·6H₂O as rare earth source,Fe（NO₃）₃·9H₂O as iron source and KOH as precipitant,Eu Fe O₃nanopowders were prepared by carbon adsorption hydrothermal method.It was characterized by TG-DTA,XRD,UV-vis,BET and TEM.The characterization results of the catalysts showed that the Eu Fe O₃nanopowders obtained by carbon adsorption co-precipitation method and calcination at 600°C for 4 h had a large specific surface area.is 29.5 m²/g.Compared with the ordinary precipitation method,the rare earth ferrite has smaller particle size,the average particle size is 66 nm,better crystallinity and smaller sintering degree.The addition of carbon black in the catalyst preparation effectively controlled the size of the particles,making the prepared particles have larger specific surface area.The methyl orange（MO）aqueous solution commonly seen in production and life was selected for reaction,and the photocatalytic activity of nanopowders was investigated by the catalytic degradation of MO in the reaction system.Preparation of Eu Fe O₃Powder by Carbon Adsorption Calcination at 600℃,The peak value of photocatalytic MO degradation rate within 60 min was 88.63%,2.8 times that of the catalyst prepared by coprecipitation method.（2）Using Sm（NO₃）₃·6H₂O as rare earth source,Fe（NO₃）₃·9H₂O as iron source,and KOH as precipitant,Sm Fe O₃nanopowders were prepared by carbon adsorption hydrothermal method,and characterized by TG-DTA,XRD,UV-vis,BET and TEM.The results show that the average particle size and specific surface area of Sm Fe O₃calcined at600℃are 64 nm and 26.1 m²/g.After 80 min of photocatalytic degradation,MO was almost completely decomposed,and the degradation rate of MO in the solution was as high as 98.59%,which was more than 2.6 times that of Sm Fe O₃catalyst prepared by ordinary precipitation method.