Electrodeposition and characterization of Fe-Mo alloys as cathodes for hydrogen evolution in the process of chlorate production

Abstract

Fe–Mo alloys were electrodeposited from a pyrophosphate bath using a single diode rectified AC current. Their composition and morphology were investigated by SEM, optical microscopy and EDS, in order to determine the influence of the deposition conditions on the morphology and composition of these alloys. It was shown that the electrodeposition parameters, such as chemical bath composition and current density, influenced both the composition of the Fe–Mo alloys and the current efficiency for their deposition, while the micro and macro-morphology did not change significantly with changing conditions of alloy electrodeposition. It was found that the electrodeposited Fe–Mo alloys possessed a 0.15 V to 0.30 V lower overvoltage than mild steel for hydrogen evolution in an electrolyte commonly used in commercial chlorate production, depending on the alloy composition, i.e., the conditions of alloy electrodeposition.

Fe–Mo legure su elektrohemijski taložene iz pirofosfatnog kupatila korišćenjem periodično promeljivog AC strujnog režima. Sastav i morfologija dobijenih taloga ispitivani su SEM i EDS tehnikama, dok je poprečni presek uzoraka ispitivan optičkom mikroskopijom, sa ciljem da se odredi uticaj uslova taloženja na morfologiju i sastav legura. Pokazano je da uslovi taloženja sastav kupatila i gustina struje taloženja, praktič no ne utiču na morfologiju legura, ali da utiču na sastav legura i na iskorišćenje struje njihovog taloženja. Takođe je pokazano da istaložene Fe–Mo legure posedujumanju prenapetost za reakciju izdvajanja vodonika od mekog čelika (0,15 V do 0,30 V u zavisnosti od uslova taloženja) koji se koristi kao katoda u industrijskim postrojenjima za proizvodnju hlorata, ukazujući da se elektrohemijski istaložene Fe–Mo legure mogu koristiti kao katalitički aktivne katode u ovom procesu.