Synthesis of a new chitosan- p-tert -butylcalix[4]arene polymer as adsorbent for toxic mercury ion

Abstract

In this paper, we have synthesized a novel chitosan- p-tert -butylcalix[4]arene polymer (CCP) as a highly efficient adsorbent for mercury ion (Hg 2+ ) removal from water. In fact, a lower rim diamine derivative of p-tert -butylcalix[4]arene has been cross-linked with chitosan chain by carbonyl diimidazole (CDI) as the linker. CDI forms a urea linkage between calix[4]arene diamine derivative and amine groups of the chitosan polymeric chain. The structure and properties of the new polymer were characterized by Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscope. Also, the adsorption capacity of CCP was studied towards Hg 2+ in aqueous medium by inductively coupled plasma-optical emission spectrometry. Interestingly, the results showed a considerable adsorption capacity for CCP in comparison with chitosan. Therefore, CCP can be introduced as a promising adsorbent for the elimination of Hg 2+ from wastewaters. Moreover, because of the conformity of adsorption kinetic with pseudo-second-order kinetic models, it can be concluded that chemical adsorption has an important role between functional groups on CCP polymer and Hg 2+ ions. In addition, according to Freundlich isotherm, the CCP surface was heterogeneous with different functional groups.

3D mesoporous polycalix-functionalized dual Brønsted–Lewis acidic double-charged DABCO-based ionic liquid: a powerful and recyclable supramolecular polymeric catalyst for the synthesis of spiro-fused[4H-pyran]

“…[36][37][38][39] The most practical procedure used to improve polymer efficiency for diverse applications is the functionalization of polymers. [40][41][42][43][44] In this respect, a 3D mesoporous organic polymer based on cone-like Cis-calix [4]resorcinarenes (3D-PC4RA) has shown good chemical reactivity due to its abundant phenolic hydroxyl groups with nucleophilic substitutions of the aromatic ring on the lower rim (that facilitate functionalization, including silylation, acylation, and alkylation) and hydrophobic cavities on the upper rim (that can encapsulate a variety of guest molecules). These two factors enhance their potential for assembling multifunctional materials.…”

Synthesis and characterization of a new reusable calix[4]arene-bonded silica gel sorbent for antidiabetic drugs

“…13 Due to unique geometry that calixarenes possess, and the availability of active functional groups, calixarenes have found various synthetic and chemical applications. 14,15 Many investigations are carried out on the adsorption performance of chemically bonded calixarene to silica gel. 16,17 A notable example is the modication of a silica resin by p-tert-butyl calix[4]arene, where the resulting sorbent is conveniently applied for selective binding to azo dyes.…”