The use of acrylic yarn modified with amidoxime and carboxylate-containing polymer for lead removal from drinking water

Amidoxime and carboxylate-containing polymer adsorbents derived from acrylic yarn exhibit high adsorption capacity for lead(ii) (Pb2+) ions in water. The adsorption process follows pseudo-second-order kinetics and fits the extended Langmuir isotherm model with the maximum adsorption capacity of Pb2+ with 238 mg lead per gram of the fiber at room temperature. Endothermic (Delta H degrees = 20.3 kJ per mole), spontaneous, and with the increase in the entropy of Pb2+ adsorption was observed from the thermodynamic studies. Dynamic column adsorption experiments showed that the fiber can process 4.3 L of water spiked with 1 ppm of lead(ii) solution at a flow rate of 4.4 mL per min under the specified conditions. The selectivity of Pb2+ with the competitive metal ions showed varying results with highly selective for Pb2+ in a binary solution with sodium and calcium and varying degrees of competitiveness with transition metal ions. This efficient and easily prepared fiber adsorbent appears to be a promising new material for the remediation of lead-contaminated aquatic environments and potable waters.

Automated summary

Amidoxime and carboxylate-containing polymer adsorbents derived from acrylic yarn have high adsorption capacity for Pb2+ ions in water. The adsorption process follows pseudo-second-order kinetics and fits the extended Langmuir isotherm model. Thermodynamic studies show endothermic, spontaneous adsorption with increased entropy. Dynamic column adsorption experiments demonstrate the efficiency of the fiber adsorbent in treating lead-contaminated water. However, the selectivity of Pb2+ varies with different competitive metal ions.