Removal of Acid Red 27, Reactive Black 5 and Acid Green 16 from Aqueous Solutions using Potassium Ferrate(VI)

Abstract

The article presents the possibility of using potassium ferrate(VI) (K2FeO4) to remove dyes (Acid Red 27, Reactive Black 5, Acid Green 16) belonging to the single azo, double azo and triarylmethane classes from aqueous solutions with an initial concentration of 100 mg/l (Chemical Oxygen Demand (COD) values for AR27, RB5 and AG16 sulutions were 172, 156 and 198 mg O2/l, respectively). For the most favorable values of oxidation parameters of AR27 and RB5 (pH 7, K2FeO4 concentration, 180 and 240 mg/l, respectively, reaction time 10 min), visual discolouration of the aqueous solutions investigated and a decrease in COD values of 83.7% and 81.4%, respectively, were achieved. In the case of AG 16 dye, in the most favorable conditions of the oxidation process (pH 3, K2FeO4, concentration 300 mg/l, 15 min), visual discolouration and a decrease in the COD value of 83.8% were also obtained. The probable reasons for the higher resistance of AG16 to oxidation using K2FeO4 compared to AR27 and RB5 were also explained, based on the analysis of the structure and type of bonds present in the molecule AG 16.

Application of Potassium Ferrate(VI) in the Treatment of Selected Water and Wastewater Pollutants – Short Review

“…In addition to the currently used purification methods: physical, chemical and biological, which often do not give satisfactory results, further, more innovative methods of wastewater treatment are being developed. One of such very promising and alternative methods, which are still mainly in the field of laboratory research, may be the use of K 2 FeO 4 , which is a compound with highly oxidizing and coagulating properties [49,50,51]. On the one hand, as a result of contact with contaminants, it acts as an oxidizer, while Fe(VI) ions are simultaneously reduced to Fe(III), Fe(OH) 3 can be precipitated, which acts as a coagulant.…”