Study on the matching of adsorption rate and photocatalytic rate under electric field synergy to enhance the degradation performance of cyclohexane

Abstract

The mismatch between the adsorption rate and the photocatalytic rate in the degradation of cyclohexane severely limits the degradation efficiency of cyclohexane. In order to improve the performance of adsorption-photocatalysis, this study significantly improved the photocatalytic performance by iron modification and application of uniform electric field. The kinetic equations of adsorption and photocatalysis were fitted by conducting cyclohexane degradation experiments, and then a theoretical model for rate adjustment was constructed. The results show that the surface iron doping in TiO₂ has a high degree of dispersion; the Fe-TiO₂ with ACF as the support has the best homogeneity at 180 ℃; and the Fe-modified TiO₂ has a higher photocurrent, which is about four times the value of the unmodified TiO₂. The pore structure of ACF remained good after the addition of Fe-TiO₂; the optimum uniform electric field applied voltage was 2.0 V. In addition, the rate constants could be expressed in terms of the gas process variables, and the state points with the smallest difference between the adsorption rate and the photocatalytic rate were 68.58 %, 0.31 m/s and 42.44 ppm. This study provides a new avenue of research to improve the performance of adsorption photocatalysis in the degradation of cyclohexane.