Tetracycline removal from aqueous solution through photoelectrochemical oxidation process using Bi2O3/ZIF-67@GP under visible light irradiation: Effects of operational parameters, water matrix

Abstract

Tetracycline degradation was investigated using two promising technologies of photocatalysis and photoelectrochemical oxidation through Bi2O3/ZIF-67 nanocomposite coating on a graphite plat (Bi2O3/ZIF-67@GP). The physical, chemical and morphological properties of coated graphite plat were determined by XRD, SEM, EDX, CROSS, UV–Vis DRS, and PL. Photocatalytic process in optimal process conditions (pH=4.1, pollutant concentration/load of photocatalyst =0.26 mg.m2/g.L and irradiation time=86 min) showed 77% pollutant removal efficiency. The use of photoelectrochemical oxidation processes has a positive effect on the efficiency of pollutant removal, at optimal conditions (Electrode distance=5.5 mm, pH=4, voltage=1.8 V, Time=89 min, and pollutant concentration/photocatalyst load= 0.2 mg.m2/g.L), the result was showed that 97% tetracycline removal efficiency. The effect of the water matrix including NaCl, Na2SO4, NaHCO3, KCl, MgSO4, and CaCl2 in different concentrations (100–800 mg/L) was recast the initial pH=7, and the pollutant concentration/photocatalyst load=0.2 mg.m2/g.L, and the time=90 min. The investigation and results showed that the presence of inorganic cations and anions caused a constant decrease in the reaction rate.