Thermo-Responsive Molecularly Imprinted Hydrogels for Selective Adsorption and Controlled Release of Phenol From Aqueous Solution

Abstract

In this study, thermo-responsive molecularly imprinted hydrogels (T-MIHs) were developed as an effective potential adsorbent for selectively adsorption phenol from wastewater. During the process, N-isopropyl acrylamide (NIPAm) was used as thermal responsive monomer. The obtained materials were characterized in detail by fourier transform infrared (FT-IR) spectrometer, scanning electron microscope (SEM), and thermo gravimetric analysis (TGA). A series of static adsorption studies were performed to investigate the kinetics, specific adsorption equilibrium, and selective recognition ability of phenol. Reversible adsorption and release of phenol were realized by changing temperatures. Three type of phenols, namely 3-chlorophenols (3-CP), 2,4-dichlorophenol (2,4-DCP), and 2,4,6-trichlorophenol (2,4,6-TCP) were selected as model analytes to evaluate the selective recognition performance of T-MIHs. The T-MIHs have good selectivity, temperature response, and reusability, making them ideal in applying in the controlled separation and release of phenol pollutants.

Smart Adsorbents for Aquatic Environmental Remediation

“…[100] Likewise, an evaluation of the temperature effect on phenol adsorption using NIPAM found that adsorption increased to a maximum at 35 °C (near the LCST of NIPAM) but decreased upon a further rise in temperature. [101] The adsorption rate of MB and Pb 2+ on an adsorbent synthesized with PNIPAM on cellulose filaments was faster at 25 °C (lower than the LCST of PNIPAM) while desorption of MB and Pb 2+ occurred at 45 °C. [102] The increase in adsorption, up to the LCST, is attributed to the expanded form of NIPAM which provides more active sites for adsorption.…”

Magnetic Surface Molecularly Imprinted Polymer for Selective Adsorption of 4-Hydroxycoumarin

“…Recently, molecular imprinted technology (MIT) ( Chen et al, 2016 ; Xu et al, 2021 ; Zhang 2020 ), as a rising molecular recognition technology, provides a new method to overcome the mentioned problems. In MIT, a specific target molecule or a structural analogue (virtual template) was firstly employed to facilitate recognition site formation through covalent or non-covalent interaction with bulk phase by polymerization, after removing the template, a molecularly imprinted polymer (MIP) was subsequent achieved with imprinted cavities which highly match the three-dimensional shape, size and functional site of target molecule ( Gao et al, 2020 ; Pan et al, 2018 ; Si et al, 2018 ). Compared to other adsorption systems, MIPs exhibit three unique characteristics of structure predetermination, application universality and recognition specificity and are highly promising for solid phase extraction ( Zhang et al, 2020 ), chemical sensors ( Cheng et al, 2017 ; Lopez et al, 2021 ; Raziq et al, 2021 ), capillary electrophoresis ( Bezdekova et al, 2021 ), simulated antibodies ( Seitz et al, 2021 ) and chromatographic separation ( Cheng et al, 2014 ).…”

Study of the Preparation and Properties of Chrysin Binary Functional Monomer Molecularly Imprinted Polymers

“…This polymer is a material with complementary spatial structure and functional group interaction with template molecule. The molecularly imprinted polymer has a strong affinity and recognition ability for the template molecule [ 23 , 24 , 25 , 26 , 27 , 28 ]. The method has excellent prospects for application in the field or market for easy and fast molecular identification.…”