Abstract
In this study, Zirconium-modified Engelhard Titanium Silicate 4 (Na-K-ETS-4/xZr) catalysts were synthesized and evaluated for their photocatalytic efficiency in degrading crystal violet (CV) and methylene blue (MB) in aqueous solutions. The catalysts were characterized using XRD, FTIR, SEM, WDXRF, and nitrogen adsorption/desorption isotherms. The results confirmed the successful incorporation of Zr into the ETS-4 framework, with the highest Zr content reaching 9.2 wt %. The photocatalytic performance under visible light irradiation was studied at varying pH levels. The Na-K-ETS-4/6.3Zr catalyst exhibited the highest photodegradation efficiency for CV (76.6 %), while Na-K-ETS-4/8.9Zr achieved 86.6 % efficiency for MB. A combination of Engelhard Titanium Silicate 10, Na-K-ETS-10/6.3Zr and Na-K-ETS-4/8.9Zr significantly enhanced dye degradation, achieving up to 96.5 % efficiency for MB. Kinetic studies indicated that the degradation process follows a non-linear pseudo-first-order model. The catalysts also demonstrated excellent reusability, with minimal efficiency loss after five cycles, and full recovery after an ethanol wash. These findings suggest that Na-K-ETS-4/xZr is a promising candidate for environmental water treatment applications due to its efficient photodegradation performance and stability.