Synergistic effect of adsorption and photocatalysis for the degradation of toluene by TiO2 loaded on ACF modified by Zn(CH3COO)2

Activated carbon fiber (ACF) was modified by Zn(NO3)(2), ZnCl2, and Zn(CH3COO)(2)), respectively, and then, TiO2 was loaded on the modified ACFs. The adsorption and photocatalysis performance were explored through the removal of toluene, and TiO2/ACF-(Ac) modified by Zn(CH3COO)(2)) with the best toluene degradation performance was selected. The characterization results of a scanning electron microscope (SEM), X-ray diffraction spectra (XRD), and Fourier transform infrared spectrometer (FTIR) indicated that the samples were rough, and TiO2 was mainly loaded on the surface containing large amount of oxygen-containing functional groups in anatase phase. An ultraviolet-visible diffuse reflectance spectrophotometer (UV-vis DRS) revealed that the catalyst enhanced the light response range. The photoelectric chemical experiment results demonstrated that the modified ACFs remarkably improved the charge transmission and the separation efficiency of electrons and holes. The adsorption saturation time reached 40 h and toluene photodegradation rate was 70%. Four toluene degradation intermediate products were determined by GC-MS, and the removal mechanism of toluene by TiO2/ACF-(Ac) was discussed.

Automated summary

The study focused on modifying activated carbon fibers with different metal salts and loading TiO2 for the removal of toluene. Among the modified samples, TiO2/ACF-(Ac) modified by Zn(CH3COO)(2) showed the best performance in toluene degradation. Characterization results indicated rough surfaces with TiO2 mainly loaded on areas containing oxygen-containing functional groups. The modified ACFs significantly improved charge transmission and the efficiency of electron-hole separation.