Novel Integration of Hydrodynamic Cavitation Pre-Oxidation and Selective Postadsorption Using a Modified Adsorbent for Arsenic Removal From Water

Pacheco Umpire P.; Cáceres Huaylla K.; Santos dos Santos J.; Chambi C.; Cardenas Malaga M.; Yokoyama L.; Montalvo Andia J. · International Journal of Chemical Engineering (2026) · DOI: 10.1155/ijce/4556613

Resumen

Arsenic is a carcinogenic metalloid prevalent in groundwater, predominantly as As (III), the most toxic and recalcitrant species. This study evaluates a hybrid strategy coupling hydrodynamic cavitation (HC) oxidation of As (III) to As (V) with subsequent adsorption on FeCl3-modified activated carbon. HC oxidation followed a pseudo-first-order kinetic model (k = 3.02 × 10−2 min−1; R2 = 0.9754), with optimal conditions of 4 bar inlet pressure and pH 4. Adsorption equilibria were described by the Langmuir model for commercial carbon (CC), qmax = 1.99 mg·g−1, and by the Freundlich model for modified commercial carbon (MCC), KF = 0.49055 (mg·g−1) (L mg−1)1/n. Kinetics for both adsorbents were best fitted by the pseudo-first-order model (k1 = 0.08876 min−1 for CC and 0.1674 min−1 for MCC). The integrated process, HC pre-oxidation followed by MCC adsorption, improved arsenic removal by 34.68% relative to conventional adsorption. Findings support HC-assisted oxidation coupled with adsorption on Fe-modified carbon as an efficient, eco-friendly, and cost-effective option for treating waters with elevated As (III)/As (V) levels. Copyright

Instituciones: Universidad Nacional de San Agustín de Arequipa; Universidad Católica San Pablo