| dc.description.abstract | A worldwide basic human right is the availability of affordable, trustworthy, and safe water. Pollutants
of emerging concern like halogenated pharmaceuticals have been documented in all environmental
matrices. Their adverse effects on humans and biota necessitate the need for their removal from water.
The remediation of pharmaceuticals from water is a growing concern since conventional wastewater
treatment plants are not equipped effectively for the task. Owing to its simplicity of use, affordability,
and environmental friendliness, adsorption using natural and modified adsorbents appeals as a method
of remediation. This study investigated the adsorptive potential of iron-modified Kenyan zeolite by
varying contact time, initial pollutant concentration, temperature, and pH, while employing
spectrophotometric monitoring. Adsorbent characterization using EDS, XRD, SEM, FTIR, and point
of zero charge analyses provided insights into the structural and chemical changes brought by iron
modification. The sorption capacity of unmodified zeolite was 7.71, 4.35, and 5.19 mg/g for
Chloramphenicol, Ciprofloxacin, and Diclofenac potassium, respectively, while iron- modified zeolite
exhibited significantly higher capacities of 22.49, 18.43, and 15.70 mg/g, respectively. Kinetic studies
revealed that Chloramphenicol adsorption followed a pseudo-first order model, while Ciprofloxacin
and Diclofenac potassium adhered to a pseudo-second order model. Isothermal analyses indicated that
Chloramphenicol and Diclofenac potassium adsorption better fitted to the Freundlich model, whereas
Ciprofloxacin was well described by the Temkin model. Thermodynamic analysis confirmed that
adsorption onto iron-modified zeolite was spontaneous and feasible for all pollutants, with adsorption
of Chloramphenicol and Diclofenac potassium being exothermic and Ciprofloxacin’s showed
endothermic characteristics. These findings highlight the superior performance of iron-modified
Kenyan zeolite as an affordable and efficient adsorbent for pharmaceutical pollutant removal, offering
a promising solution for water treatment.
Keywords: Iron-modified zeolite, Diclofenac potassium, Chloramphenicol, Ciprofloxacin | en_US |
