Effect of inorganic salts on ferric oxalate‐induced decomposition of CI Acid Black 234 under different weather conditions

Abstract

In this study, sodium chloride and sodium sulphate were used for investigating their effects on photocatalytic decomposition of a triazo acid dye, CI Acid Black 234, used widely for the coloration of leather and wool products by the Fe III -oxalate complexes ⁄ hydrogen peroxide system under different weather conditions, respectively. Moreover, the photocatalytic degradation and mineralisation of CI Acid Black 234 was also examined by ultraviolet-visible spectrum and total organic carbon measurements. The results indicated that photocatalytic decoloration of CI Acid Black 234 was significantly limited in the presence of inorganic salt. Increasing the concentration of inorganic salt led to a lower decoloration percentage and kinetic reaction constant. The effect of inorganic salt on dye decomposition varied with solar light intensity. Sodium chloride exhibits a much stronger reduction effect on photocatalytic decoloration, degradation and mineralisation than sodium sulphate at similar reaction conditions, especially on a cloudy day.

Renovation and Reuse of Reactive Dyeing Effluent by a Novel Heterogeneous Fenton System Based on Metal Modified PTFE Fibrous Catalyst/H2O2

“…This may be due to the two competing factors. On one hand, it is obvious that the presence of salt can increase the aggregation degree of ionic dyes in water, inhabiting the dye degradation [23].On the other hand, the reaction between sulfate ions and hydroxyl radical produced by photo-Fenton reaction can generate the higher oxidative sulphate radicals, which increase the dye degradation efficiency [24].…”

Effect of inorganic anions on the photocatalytic decolorisation of an azo dye in the aqueous phase by cadmium sulphide/polymer nanocomposite films under visible light irradiation

“…In the effluent of practical dyes, various electrolytes (such as , , , Cl − and ) are added into the dyebath in the textile industries in order to improve colour fastness [10] or to retard dyeing rates [11]. Therefore, the effects of coexisting anions on photocatalytic decolorisation and degradation of dye wastewater cannot be neglected as the occurrence of dissolved inorganic ions is rather common in dye‐containing industrial wastewater.…”