Abstract:
High fluoride intake (>1.0mgL-1) can cause a variety of fluorosis-related
diseases that are common in some tank cascade systems. However, removing excess
fluoride from water is still a pressing global concern. Nanotechnological approaches,
among many emerging defluoridation techniques, showed high efficiency and sim-
plicity of usage. This study is mainly focused on the defluoridation of drinking water
using the Zeolite minerals-based -nanocomposite; that is modified with hexadecyltri-
methylammonium ions (HDTMA+) and L-lysine. Modified zeolites were character-
ized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD),
Thermos-gravimetric analysis (TGA), and differential scanning calorimeter analysis
(DSC). Batch sorption studies were demonstrated to determine the performance of the
developed Zeolite nanocomposite material, based on different parameters, such as pH,
contact time competitor anions, and initial fluoride concentration. The maximum flu-
oride removal was reported at an initial pH of 5.0 and 9.0 respectively for HDTMA-
modified and L-lysine-modified zeolite. The maximum sorption capacity of fluoride
by Langmuir isotherm was found to be 33.40 mg g-1 and 10 mg g-1 respectively for
HDTMA-modified and L-lysine-modified zeolite. It is demonstrated that initial flu-
oride concentration (1–10 mg L-1) to fast fluoride uptakes at a potency of 6.0 g L-1 for
both modified Zeolite nanocomposites, and significant fluoride removal capacity with
the 45-min contact time. Studies on regeneration with NaCl were effective after the
18-20 cycle of us
