Preparation Of Bamboo-carbon Supported Iron Catalyst And Study On Removal Of Oxytetracycline Hydrochloride In Water

Oxytetracycline hydrochloride belongs to tetracycline antibiotics,which is potentially toxic to humans.Some of its degradation by-products are more toxic than the parent and are difficult to be removed with conventional treatment methods.Catalytic oxidation technology has become an emerging technology in the field of waste water treatment.However,using Fe2+ as a catalyst has problems like generation of iron mud and increasement of chroma.Therefore,the development of high-efficiency,non-iron-producing and easy to recycle and separate catalysts has become a new research hotspot.In this study,Fe-BC composite catalysts was prepared by solution impregnation method.The composition and morphology of the composite catalyst were characterized by XRD,SEM and EDS.On this basis,various influencing factors and their regularities of degradation of oxytetracycline hydrochloride in water by Fe-BC composite catalyst were investigated in detail.The degradation of oxytetracycline hydrochloride in heterogeneous Fenton and heterogeneous photo-Fenton reaction system was analyzed.The following conclusions have been reached:(1)Fe-BC composite catalyst was successfully prepared by using bamboo charcoal as the carrier and solution impregnation method with ferrous sulfate as raw material and calcination at 300 ℃.The characterization results show that the iron oxide has been loaded on the surface of bamboo charcoal.The composite catalyst is easily separated and recycled.The surface of the composite catalyst after the coating is covered with a dense iron oxide film,and the surface of the composite catalyst is scattered with Fe2O3 and Fe3O4 particles,which increases the specific surface area of the bamboo charcoal.(2)The amount of Fe-BC composite catalyst,H2O2 dosage and pH are the main factors which affect the removal efficiency.When the dosage of Fe-BC composite catalyst was 6g/L,the concentration of oxytetracycline hydrochloride was 200 mg/L,the pH=3.67,the adsorption reaction was 30 min,and the catalytic reaction was 60 min,the removal rate of oxytetracycline hydrochloride can reach 92.3%.(3)The addition of ultraviolet light and composite photocatalyst synergistically,the pH reaction range is extended to 2～10.When the dosage of Fe-BC composite catalyst was 6 g/L,the concentration of oxytetracycline hydrochloride was 200 mg/L,the pH=3.67,the adsorption reaction was 30 min and the catalytic reaction was 60 min under 60 W ultraviolet light(light intensity is 7.3×104 W/m3),the removal rate of oxytetracycline hydrochloride is 94.2%,which increases by 1.9%comparing with heterogeneous Fenton oxidation.(4)In the stability test of Fe-BC composite catalyst,it was found that the removal rate of Fe-BC composite catalyst can be kept at about 70%when it was used within three times,which shows the good stability.After four times,the removal rate drops to 60.17%,which cannot be used indefinitely,and the load stability still needs to be improved.(5)The Fe-BC composite catalyst has a good linear correlation with the degradation trend line of oxytetracycline hydrochloride,which accords with first-order reaction kinetics model.