Defluoridation of drinking water by modified natural zeolite with Cationic surfactant, in the case of Ziway town, Ethiopia

Abstract

Excessive fluoride intake in drinking water sources in Ethiopia (Ziway town) causes health issues in the residents. The goal of this study was to utilize the defluoridation of drinking water using clinoptilolite zeolite modified with a cationic surfactant Hexadecy Trimethyl Ammonium Bromine. The treatment’s removal efficiency has been optimized by the pH of the solution (5.5 ± 0.2–8.5 ± 0.2), initial fluoridated water (1–10 mg/L) to fast fluoride removal at a potency of 5.5 g/L, dose of surfactant modified zeolite (2.5–18 g/L), contact time (30-min, and the effect of temperature (80–120 ◦C), which better removal efficiency as temperature increased. The study was examined, at the constant Blank of 10 mg/L, 5 g/L of Hexadecy Trimethyl Ammonium Bromine dosage records the highest fluoride removal potential at the end of the60 min runtime: Sodium Low Silica X (Na-SX) (88.4%), Sodium Linde Type A (Na-LTA) (64.6%) and Reagent only Zeolite (ZR) (25%). Incompatible with this reflection, the model waters with pH maintained at 5.5 ± 0.2 and 6.5 ± 0.2 verified rapid fluoride removal (89.7% and 72.3% respectively) within the first 3 h of runtime. The best performance of this treatment efficiency were obtained at pH (5.5–8.5), stock solution ≤ 10 mg/L, adsorbent dose ≤ 18, and more delayed time. The findings of this study indicated that unmodified clinoptilolite zeolite was incapable of adsorbing fluoride ions, but the surfactant-modified zeolite adsorbed fluoride but requires adequate pH control, temperature, and running times. The coincidence of large amount of natural zeolite and high level of fluoride in drinking water in Ethiopian rift valley areas pulls the very vital aspect, which requires the modified treatment technology.