Study On Photocatalytic Purification Of Formaldhyde By Synergistic Effect Of Graphene Or CNTs And Nano TiO₂/ACF

In this article, TiO2/ACF, CNTs/TiO2/ACF and Graphene/TiO2/ACF were prepared by the immersion and spray painting method,and absorb and photocatalytic degradate the target pollutant formaldehyde in a self-made decontamination equipment under254nm UV light illumination at normal pressure and temperature. The concentration of the formaldehyde before and after the deconamiation was detected by using diacetylmethane spectrophotometry, looking for the best capacity of TiO2loading on ACF, the best usage amount of CNTs and Graphene and the best usage amount of multi-times connection of equal quantity formaldehyde decontamination gases.Research showed that formaldehyde purification efficiency of TiO2/VACF photocatalysis was not merely change in pace with the load rate, but had a maximum value.Through experiment, TiO2/ACF had the highest photocatalysis efficiency with a load rate of4.4%; efficiency of TiO2/ACF photocatalysis decomposition decreased with the extension of the adsorption. Whencame to a certain degree,the effect of TiO2/ACF photocatalysis became worse; When usage amount increased, formaldehydepurifycation efficiency of TiO2/ACF gradually raised gradually; when using six timesof the unitage of TiO2/ACF, the purification efficiency reached100%and maintained the same efficiency for along time.Through the experiment, formaldehyde purification efficiency of CNTs/TiO2/ACF photocatalysis was not merely change in pace with the load rate, but had a maximum value. TiO2/ACF had the highest photocatalysis efficiency with a load rate of0.3%; efficiency of CNTs/TiO2/ACF photocatalysis decomposition decreased with the extension of adsorption time.when came to a certain degree, the effect of CNTs/TiO2/ACF photocatalysis became worse. When the usage amount is equal to the amount of multi-times connection of equal quantity formaldehyde decontamination gases, the formaldehyde purification efficiency of CNTs/TiO2/ACF photocatalysis raised gradually. Formaldehyde purification efficiency of Graphene/TiO2/ACF photocatalysis was not merely change in pace with the load rate, but had a maximum value.Through experiment, Grapheme/TiO2/ACF had the highest photocatalysis efficiency with a load rate of0.05%; efficiency of CNTs/TiO2/ACF photocatalysis decomposition decreased with theextension of adsorption, and, when came to a certain degree, the effect of the TiO2/ACF photocatalysis became worse. When the usage amount is equal to the amount of multi-times connection of equal quantity formaldehyde decontamination gases, the formaldehyde purification efficiency of Graphene/TiO2/ACFphotocatalysis raised gradually.Through comparing amonge the effecet of formaldehyde decontamination of same unitages of TiO2/ACF、CNTs/TiO2/ACF and Graphene/TiO2/ACF and dynamic analysis,a conclusion came out that Graphene/TiO2/ACF has a best degradation effect followed by CNTs/TiO2/ACF, and TiO2/ACF the worst.The research found that through recycling six times of the unitage of TiO2/ACF, three times of the unitage of Graphene/TiO2/ACF and CNTs/TiO2/ACF at a long time interval, the post photocatalytic degradation ability had rebounded. With batch-type interruption of gas flow and light in this chemical reaction, the formaldehyde purification process can come out a effect of "apparent self-cleaning and regeneration".SEM test and specific surface and aperture test showed that the structure, surfacial area and aperture had changed little after loading, making not only TiO2/ACF, CNTs/TiO2/ACF, and Graphene/TiO2/ACF had big adsorption performance, but also with the existence of CNTs, Graphen can raise the photocatalytic efficiency.This research mainly compared the photocatalytic performance of TiO2/ACF, CNTs/TiO2/ACF and Graphene/TiO2/ACF. The results could provide new effective way to decontaminate air pollution and have certain significance in improving the quality of human life and environmental safty.