Faujasite-Type Zeolite Obtained from Ecuadorian Clay as a Support of ZnTiO3/TiO2 NPs for Cyanide Removal in Aqueous Solutions

Abstract

In this study, zeolites prepared by the hydrothermal method from Ecuadorian clay were combined with the precursor clay and with the semiconductor ZnTiO3/TiO2 prepared by the sol-gel method to adsorb and photodegrade cyanide species from aqueous solutions. These compounds were characterized by X-ray powder diffraction, X-ray fluorescence, scanning electron microscopy, energy-dispersive X-rays, point of zero charge, and specific surface area. The adsorption characteristics of the compounds were measured using batch adsorption experiments as a function of pH, initial concentration, temperature, and contact time. The Langmuir isotherm model and the pseudo-second-order model fit the adsorption process better. The equilibrium state in the reaction systems at pH = 7 was reached around 130 and 60 min in the adsorption and photodegradation experiments, respectively. The maximum cyanide adsorption value (73.37 mg g−1) was obtained with the ZC compound (zeolite + clay), and the maximum cyanide photodegradation capacity (90.7%) under UV light was obtained with the TC compound (ZnTiO3/TiO2 + clay). Finally, the reuse of the compounds in five consecutive treatment cycles was determined. The results reflect that the compounds synthesized and adapted to the extruded form could potentially be used for the removal of cyanide from wastewater.

Cyanide Removal by ZnTiO3/TiO2/H2O2/UVB System: A Theoretical-Experimental Approach

“…The coupled semiconductor ZnTiO 3 /TiO 2 , which integrates zinc titanate (ZnTiO 3 ) with TiO 2 , has been explored for the removal of various pollutants in wastewater due to its molecular properties and adsorption and photocatalysis characteristics [41,42]. This hybrid semiconductor exhibits superior physical and chemical properties compared to individual components, primarily due to alterations in their electronic states.…”

Perovskite Nano-Powder and Nano-Film Catalysts in Mineralization of Aqueous Organic Contaminants through Solar Simulated Radiation

“…For the ZnTiO3 and MnTiO3 materials, the PZC values were ~7.80 and ~7.83. ZnTiO3 has a PZC value reported in the literature within the range of 7.00-7.60 [51,52], depending on the presence of TiO2. For MnTiO3, the present high values were due to the mixed phase with TiO2, as reported earlier [53].…”