Comparison for the Adsorption of Catechol and Hydroquinone on Activated Carbon Fibre: Kinetic Analysis
2019
Mingzhao Shen, Meiya Zhu, Jintao Sun, Yunlong Zhang, Rong Li, Fang Niu, Shiying Li, Xiao Mi and Guoting Li
Catechol and hydroquinone are widely applied in industrial synthesis while they are typical toxic organic pollutants. Efficient adsorptive removal of catechol and hydroquinone is highly needed. In this research, activated carbon fibre (ACF) was used for the kinetic removal of the two pollutants. As catechol and hydroquinone have different pKa values, it was found that the highest uptake of catechol and hydroquinone was observed at pH 11.0 and 5.0, respectively. The adsorption kinetics for catechol and hydroquinone were compared. The removal of hydroquinone is higher than that of catechol at almost all the pH conditions. At pH 7.0, the uptake of catechol and hydroquinone on ACF were 125.8 and 200.4 mg/g, respectively. As both Elovich and pseudo-second-order kinetic models could better describe the adsorption process, the adsorption of catechol and hydroquinone onto ACF might be chemisorption. The rate determining step might be diffusive in nature for the uptake of catechol and hydroquinone. Linear pseudo-second-order kinetic model fitted the experimental data better than pseudo-first-order kinetic model. The presence of natural organic matter, humic acid, could inhibit the uptake of catechol and hydroquinone on ACF profoundly.
显示更多 [+] 显示较少 [-]