Electrocatalytic hydrodechlorination of pentachlorophenol on Pd-supported magnetic biochar particle electrodes

Abstract

To enhance the catalytic activity of Pd and to facilitate rapid recovery, a novel Pd/CuFe2O4/peanut shell-derived biochar (Pd/M−PSBC) particle electrode was developed and applied toward the electrocatalytic hydrodechlorination of pentachlorophenol (PCP) in a three-dimensional reactor. The physicochemical properties and the electrochemical performance of the particle electrode were systematically characterized through a series of characterizations, such as scanning electron microscopy, high resolution transmission electron microscopy, X-ray photoelectron spectroscopy and linear sweep voltammetry. The results demonstrate a uniform Pd distribution across the M−PSBC surface having an average particle size of 5 nm. Furthermore, the Pd/M−PSBC electrode exhibited outstanding hydrogen adsorption activity. Under optimal experimental conditions, voltage of 0.8 V, particle electrode dosage of 20 mg (2.2 wt% Pd loading), the PCP (50 mg/L) removal efficiency and the dechlorination efficiency reached 99.0% and 93.1%, respectively. By undertaking consecutive cycling experiments the stability of the Pd/M−PSBC electrode toward PCP dechlorination was observed to be excellent. Finally, a toxicity assessment confirmed the reduction of PCP and PCP intermediate toxicities.