Capability of copper-nickel ferrite nanoparticles loaded onto multi-walled carbon nanotubes to degrade acid blue 113 dye in the sonophotocatalytic treatment process

In this study, copper-nickel ferrite (CuNiFe2O4) nanoparticles were successfully loaded onto multi-walled carbon nanotubes (MWCNTs) by using the coprecipitation method and used as new catalysts (MWCNT-CuNiFe2O4) in the sonophotocatalytic degradation process of the acid blue 113 (AB113) dye. The success of the MWCNT-CuNiFe2O4 synthesis and its properties were determined by analyzing it using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). A high efficiency of dye removal (100%), total organic carbon (93%), and chemical oxygen demand (95%) were achieved with the following conditions: pH of dye solution = 5, MWCNT-CuNiFe2O4 dosage = 0.6 g/L, AB113 dye concentration = 50 mg/L, UV light intensity = 36 W, ultrasonic wave frequency = 35 kHz, and treatment time = 30 min. The kinetic results revealed that the efficiency of the sonophotocatalytic process using MWCNT-CuNiFe2O4 was higher than that of the sonolysis, photolysis, photocatalysis, and sonocatalysis processes. Scavenging studies demonstrated that the holes (h(+)) and hydroxyl radical (center dot OH) were the main reactive species for the AB113 dye degradation. The stability and recyclability of MWCNT-CuNiFe2O4 were confirmed with eight consecutive cycles for a maximum efficiency of more than 92%. The high rate of BOD5/COD indicated that the sonophotocatalytic process had the potential to degrade the dye into degradable compounds. The toxicity study with an Escherichia coli growth inhibition rate emphasized that MWCNT-CuNiFe2O4 in the sonophotocatalytic degradation process of the AB113 dye had a significant effect on reducing toxicity, when compared to processes of photolysis and photocatalysis. During the sonophotocatalytic process using MWCNT-CuNiFe2O4, the AB113 dye was mineralized into CO2, H2O, NH4+, NO3-, and SO42-. The results of the present study proved that the MWCNT-CuNiFe2O4-based sonophotocatalytic process was a promising dye degradation technology to protect the aquatic environment.

Automated summary

In this study, CuNiFe2O4 nanoparticles were loaded onto MWCNTs and used as catalysts in the sonophotocatalytic degradation of AB113 dye. The efficiency of dye removal and the potential for protecting the aquatic environment were demonstrated.