Study On The Controllable Preparation Of C_3AP/R-F/TiO₂ Composite Material And Its Adsorption Performance For Chloramphenicol And Safranine T

Antibiotic wastewater and dye wastewater are two common organic pollutants.Chloramphenicol is a kind of widely used antibiotics,low concentration of residues can also pose a threat to human.Safranine T,as a typical cationic dye,exists in surface waters for a long time,which not only increases the chromaticity of water,but also causes toxicity to aquatic organisms and human.Adsorption is often used to remove antibiotics and dyes in water due to its advantages of safety,convenient operation and low cost.Therefore,it is very meaningful to prepare an adsorbent that has high-efficiency adsorption performance for the two pollutants.Phenolic resin has a high carbon retention rate after carbonization and is used for preparing carbon material.Titanium dioxide has been shown to have a certain adsorption capacity after compound.This research aims to develop high-efficiency adsorbents,design a nano-adsorbent composed of carbon and titanium dioxide with a special spatial structure,and compare its adsorption performance;for the optimal adsorbent,investigate its adsorption performance and adsorption mechanism for different types of pollutants.The main research content of this thesis can result in the following aspects:（1）In this paper,four kinds of nanomaterials with different spatial structures are prepared.3AP/R-F is prepared by sol-gel method,and C_3AP/R-F is obtained by nitrogen carbonization;Use TBOT to hydrolyze in water to prepare 3AP/R-F@TiO₂ with a core-shell structure,and obtain C_3AP/R-F/TiO₂ after carbonization with nitrogen;use TEOS to hydrolyze in water and use 3AP/R-F@TiO₂ as the core to synthesize a double-shell structure 3AP/R-F@TiO₂@Si O₂,calcined with nitrogen,and etched with Na OH to remove silicon to obtain a complete core-shell structure of C_3AP/R-F@TiO₂;C_3AP/R-F/TiO₂ is calcined in an air atmosphere to make a as-prepared TiO₂ particles.In the experiment,the crystalline form of titanium dioxide in C_3AP/R-F/TiO₂ was controlled by adjusting the calcination temperature;the wall thickness was controlled by changing the amount of TBOT.This article uses TEM,XRD,BET and TGA for characterization.（2）The adsorption capacity of the four adsorbents for chloramphenicol was investigated,and the order of adsorption capacity from small to large is as follows:TiO₂<C_3AP/R-F<C_3AP/R-F@TiO₂<C_3AP/R-F/TiO₂.With chloramphenicol as the target pollutant,the adsorption capacity of C_3AP/R-F/TiO₂ on antibiotic pollution was studied.Under the initial conditions of reaction temperature of 25℃,reaction system of 50.00 m L,C_3AP/R-F/TiO₂ dosage of 0.40 g/L,the adsorption capacity of C_3AP/R-F/TiO₂ for chloramphenicol reached 11.30 mg/g after 2 h reaction,and about 98%of chloramphenicol was removed.Studying the effect of the calcination temperature and the amount of TBOT on its adsorption capacity,the results show that the higher the calcination temperature,the better the adsorption effect of the material on chloramphenicol;the more the amount of precursor TBOT,the adsorption effect of the material on chloramphenicol will increase first and then decrease.The p H of the solution and the concentration of coexisting ion Cl^-have no significant effect on the adsorption of chloramphenicol on C_3AP/R-F/TiO₂.Combined with the kinetic study and isotherm fitting,the adsorption characteristics of C_3AP/R-F/TiO₂ to chloramphenicol were analyzed.The recovery and reuse experiment of the adsorbent after adsorbing chloramphenicol showed that the removal rate of chloramphenicol was 98%during the first use,and after three repetitions,the adsorption effect was stable.（3）With saffron T as the target pollutant,the adsorption capacity of C_3AP/R-F/TiO₂ on dye pollutants was investigated.The results showed that under the initial conditions of reaction temperature of 25℃,reaction system of 50.00 m L,C_3AP/R-F/TiO₂ dosage of 0.30 g/L,the adsorption capacity of C_3AP/R-F/TiO₂ to saffron T reached 165.03 mg/g for 2 hours,and about100%of the saffron T was removed.When the solution increases from acidic to neutral,the adsorption capacity increases;when it increases to alkaline,the effect does not change significantly.Increasing the Cl^-concentration is too high,and the ability to adsorb saffron T decreases.Combined with the kinetic study and isotherm fitting,the adsorption characteristics of C_3AP/R-F/TiO₂ to chloramphenicol were analyzed.The recovery and reuse experiment of the adsorbent after the adsorption of the saffron T showed that the removal rate of the saffron T was stable at 98%after three times of repeated utilization,which indicated that the C_3AP/R-F/TiO₂ had a good repeated adsorption effect on the saffron T and had a good practical value.