Studying the performance of montmorillonite-CuFe2O4 nanocomposite for peroxymonosulfate activation in acid red 18 dye degradation

The effluent from textile industries contains various metal pollutants and organic substances, which have attracted the attention of environmental engineers in recent decades. Methods based on advanced oxidation processes such as peroxymonosulfate (PMS) activation are excellent techniques for destroying organic pollutants such as dye with a complex structure. In the present study, copper ferrite nanoparticles (CuFe2O4) loaded on montmorillonite (MMT) were used as PMS activating catalyst in the decomposition of acid red 18 dye.

The MMT-CuFe2O4 catalyst was prepared by sol-gel method, and its properties were determined through TEM, SEM-EDX, XRD, and FTIR analysis. Optimum conditions for maximum dye removal were predicted through response surface methodology (RSM). The effect of anions on the rate of dye decomposition and catalyst stability was carried out as additional tests in the present study.

Diagnostic analyses showed that CuFe2O4 nanoparticles with nanometer size were loaded on the surface of MMT. The results of statistical analysis with R2 = 0.977 and F = 114.27 showed that the parameters were effective on the catalytic decomposition of dye. Maximum dye removal efficiency (99.66%) was predicted by the RSM model in optimal conditions including pH of 8.93, PMS dosage of 1.18 mM, catalyst dosage of 228 mg/L, and reaction time of 9.66 min. The presence of various anions in the reaction medium reduced the efficiency from 100% to 85%.

Based on the results, MMT-CuFe2O4 is a good candidate for treatment of the aqueous solution containing acid red 18 dye.