Preparation Of Tubular Copper Sulfide And Its Performance On Tetracycline Removal From Water

In recent years,the production and use of tetracycline have caused serious water pollution.How to remove tetracycline pollution in water has become a research hotspot in the direction of water pollution control.Based on the synthesis of a series of copper sulfide with different morphologies,this thesis selected two tubular copper sulfides as the research objects by characterizing their physical and chemical properties,investigated their adsorption performance and mechanism for tetracycline in water,and explored their The photocatalytic degradation performance of tetracycline in water.The main findings are as follows:（1）10 kinds of copper sulfide with different morphologies were synthesized by hydrothermal and solvothermal methods,and their physical and chemical properties were characterized by BET,SEM,XRD,FTIR and other analytical methods.The results show that the morphology of the synthesized samples includes cactus,rod,tube and mulberry,and the particle size is micron level.All samples except BX-50 are pure indigo copper sulfide,and the synthesized copper sulfide samples are mesoporous materials.The specific surface area is between 26～37.6 m²/g,and the band gap is in the range of 0.71～1.25 e V.（2）Using BY-28 and BX-80 two kinds of tubular copper sulfide with superior physical and chemical properties as adsorption materials,the removal performance of the two kinds of copper sulfide on tetracycline in water under different p H conditions was studied;and their effect on tetracycline was further studied.The adsorption kinetics,adsorption isotherms,and desorption performance after adsorption saturation.The results show that the optimal adsorption p H of the two copper sulfides are 6.19 and 6.37,respectively;the adsorption kinetic data of BY-28 and BX-80 copper sulfide on tetracycline in water conform to the pseudo-second-order kinetic model,and the adsorption equilibrium times are respectively 3000 min and 6000min,that is,BY-28 has a faster adsorption rate.Their adsorption isotherms are in line with the Langmuir model.The saturated adsorption capacities at 298 K are 2339.1 mg/L and 1863.1mg/L,respectively,which proves that the synthesized BY-28 has better adsorption performance;using 0.03 M HCl+60%Ethanol desorption solution desorbed BY-28 and BX-80 after adsorption saturation,and the desorption rates were 99.0%and 94.6%,respectively;comparing the infrared spectra before and after adsorption,it was found that tetracycline bound to the two copper sulfide surfaces The positions are mainly the amide group,carbonyl group and dimethylamino group at 1523 cm^-1,1671 cm^-1 and 2928 cm^-1 on the A ring,and the carbonyl group on the C ring.（3）Using tubular copper sulfide BY-28 as the photocatalyst,the effects of p H value,catalyst dosage and light source type on the catalytic effect of BY-28 were studied,and the relationship between adsorption and photocatalysis and the system were further investigated.Active species.The experimental results show that the optimal initial p H of the tubular copper sulfide BY-28 photocatalytic degradation of tetracycline in water is 8,and the optimal catalyst dosage is 0.2 g/L.Under ultraviolet light irradiation,the removal rate of high-concentration tetracycline solution with an initial concentration of 200 mg/L can reach more than 90%in 180minutes,indicating that BY-28 has good photocatalytic degradation performance for tetracycline in water.In addition,studies on the relationship between photocatalysis and adsorption show that the presence of photocatalysis can increase the removal effect of copper sulfide,which proves that photocatalysis and adsorption are synergistic in the process of copper sulfide photodegradation of tetracycline.The results of free radical capture experiments show that the main active species in the reaction system are photo-generated holes（h⁺）and superoxide radicals(·O^2-).In summary,the tubular copper sulfide BY-28 synthesized in this paper is a new type of copper sulfide material with higher stability than amorphous copper sulfide.It has good adsorption performance and photocatalytic degradation performance for tetracycline hydrochloride in water,and can be used as an adsorbent.He photocatalyst treats high-concentration tetracycline wastewater,and can also provide theoretical support and technical support for the removal of other antibiotic pollutants in the water.