Adsorption Behavious Of Dye And Cu²⁺Using AC@TiO₂ Microsphere

Titanium dioxide(TiO2)has attracted increasing attention of-numerous researchers because of the nature of stability,non-toxic pollution,and low cost.However,particle size of the single TiO2 is small,and it is not easy to separation and easy reunion in aqueous solution,thus easy to cause secondary pollution.Granular activated carbon(AC)because of its nature is stable,strong adsorption ability,and wide pore size distribution,therefor combining TiO2 with AC can effectively solve the problems of TiO2 in the process of adsorption.At present,the method has become one of the commonly modified TiO2.In this paper,butyl titanate as the titanium source and granular activated carbon as a carrier was selected and granular TiO2 composite had been prepared by sol-gel method.Material prepared was characterized by scanning electron microscope techniques(SEM)、X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FT-IR).With acid dye methyl orange(MO),alkaline dye methylene blue(MB)and heavy metal ions(Cu2+)as simulated wastewater,the sorption performance of composites and the influencing factors were evaluated in the single and binary(MO and Cu2+,MB and Cu2+)system.The adsorptive influence factors of time and solution pH had been studied in the single system.The adsorption of AC@TiO2 for MO would be promoted under acidity condition,the adsorption of MB and Cu2+ would be improved under alkalecent condition,and the adsorption rate of MO,MB and Cu2+ were 95.55%,90.54%and 91.55%,respectively;The adsorption equilibrium adsorption time of MO,MB and Cu2+ were 4 h,4 h and 5 h,respectively;The maximum adsorption capacity of AC＠TiO2 for MO,MB and Cu2+ were 32.4 mg/g,25.3 mg/g and 23.4 mg/g;After 5 cycles of AC@TiO2,the adsorption rate of AC@TiO2 to MO,MB and Cu2+ still reached 80%.The adsorptive influence factors of time and concentration had been studied in the binary system.Compared with the single system,the adsorption equilibrium time of AC@TiO2 for MO was 3 h in binary(MO and Cu2+)system,and the adsorption rate increased to 98.21%;Adsorption equilibrium time,and the adsorption rate of AC@TiO2 for Cu2+ has a little change.The adsorption rate of AC@TiO2 for MO would promoted firstly and late reduced under different concentrate of Cu2+ circumstances,however,the impact of MO on Cu2+ adsorption would also increased.Compared with the single system,the adsorption equilibrium time of AC@TiO2 for MB was 5 h in binary(MB and Cu2+)system,and the adsorption rate decreased to 80.18%;Adsorption equilibrium time,and the adsorption rate of AC@TiO2 for Cu2+ change little.the adsorption rate of AC@TiO2 for MB would continuously decreased under different concentrate of Cu2+ circumstances,however,the impact of MB on Cu2+ adsorption would also decreased.The reaction kinetics of AC@TiO2 for MO,MB and Cu2+ were described as pseudo-second-order kinetic model in the single and binary system;The reaction isotherms for MO,MB and Cu2+ were fitted by Langmuir model in the single system.