Preparation of modified zeolite/chitosan composites and study on the adsorption performance of Pb2+

Abstract

AbstractAs one of the most common pollutants in wastewater, heavy metals seriously threaten human health and survival, and among the current removal methods, the adsorption method has attracted the most attention because of its simple and safe operation. Zeolite is a substance with a unique spatial structure, cheap cost, and environmental friendliness. Zeolite is a substance with a unique spatial structure, cheap cost, and environmental friendliness. Due to its size and high surface area‐to‐volume ratio, zeolite exhibits excellent adsorption and ion exchange properties and is a promising adsorbent. In this paper, the modified zeolite chitosan composite film was prepared by solution method by dissolving chitosan in acetic acid solution as the solvent, and the effects of zeolite content, modifier type, initial pH, pore‐making agent, adsorption time, adsorption temperature, initial concentration, and feeding amount were studied. The optimal conditions for Pb2+ adsorption were 40% modified zeolite content, 293 K in 100 mg/L solution, a feeding amount of 1 g/L, pH = 5.5, and a removal rate of 96.6% in 24 h. The isotherm is consistent with the Langmuir adsorption model, which is manifested as single‐molecule chemical adsorption, and the highest saturated adsorption capacity is 139.6 mg/g. After five cycles, it still has a greater than 90% initial adsorption effect.Highlights Chitosan‐modified zeolite composite membranes are inexpensive. After adsorption, the sorbent is easy to recover.