Preparation of Co/Ti electrode by electro-deposition for aqueous nitrate reduction

Abstract

A Co/Ti electrode for nitrate reduction was prepared by electrode-deposition. In the single-compartment electrolysis cell, nitrate (100 mg/L) removal reached nearly 100% after 3 h electrolysis under the current density of 20 mA cm–2 by using the Co/Ti electrode as cathode, and the main reduction products were ammonium nitrogen (66.5%) and nitrogen gas (33.5%). This performance on nitrate removal was comparable to a Co3O4/Ti electrode, and the electroactivity of the Co/Ti electrode towards nitrite reduction was higher than that of a Co3O4/Ti electrode. The Co/Ti electrode exhibited an improved stability with 18.7% of mass loss and 25.5% of Co dissolution compared with the Co3O4/Ti electrode after ultrasonic interference. The presence of chlorine ion (1,000 mg/L) could promote the total nitrogen (TN) removal to approximately 100% after 3 h electrolysis because of the ammonium oxidation by the free chlorine produced from the anode. In the presence of calcium (50 mg/L) and phosphate (0.5 mg/L), the nitrate removal decreased from 85.4 ± 1.5 to 57.7 ± 3.5% after ten reuse cycles. This result suggests that Ca and P should be pre-removed before the electro-reduction of nitrate.

Ce-doped three-dimensional graphite felt/PbO2 anode: single-step room-temperature electrodeposition and efficient electrocatalytic degradation of tetracycline

“…8 EAOPs require no additional reagents, ensure high degradation efficiency, and induce relatively minor secondary pollution. [9][10][11] Notably, the choice of electrode materials in EAOPs significantly influences the production of reactive species, which determines the efficiency of electrochemical contaminant degradation. 12 Numerous researchers are dedicated to developing novel anodic electrode materials that can efficiently degrade organic pollutants like TC over a broad pH range with good activity, high stability, and lower cost.…”