A novel solid acid coating catalyst on Q235 carbon steel for Fenton-like oxidation of phenol under circumneutral pH.

Novel amorphous Fe 3 O 4 /FePO 4 /ZrO 2 ceramic coatings as solid acid with porous structure were successfully synthesized in the phosphate electrolyte containing K 2 ZrF 6 via plasma electrolytic oxidation (PEO) technique and characterized by scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The surface acidic property was investigated by NH 3 -TPD method. The results showed that the pore size and the intensity of pore interconnection of amorphous Fe 3 O 4 /FePO 4 /ZrO 2 ceramic coating with solid acid property, increased with the increase of the K 2 ZrF 6 dosage from 0.5 g to 2.0 g in the phosphate electrolyte. The Fenton-like performance of PEO coating catalysts was investigated by degradation of phenol under circumneutral pH. It was found that phenol removal efficiency decreased with the adding of K 2 ZrF 6 amount from 0.5 g to 2.0 g except no catalytic activity of coating prepared without K 2 ZrF 6 , and Fenton-like PEO coating catalyst prepared with 0.5 g K 2 ZrF 6 exhibited a superior catalytic activity which could degrade phenol thoroughly within 2 min under circumneutral pH. The strong acid sites played a dominant role in enhancing the Fenton-like catalytic activity. The excellent catalytic activity of PEO coating prepared in the phosphate electrolyte containing K 2 ZrF 6 endowed it potential application in wastewater treatment. [ABSTRACT FROM AUTHOR]