Glutathione Surface Molecularly Imprinted Polymer from CLX1180 via Three Modes of Polymerization for Selective Adsorption of Glutathione

Magnetic chitosan/TiO2 composite for vanadium(v) adsorption simultaneously being transformed to an enhanced natural photocatalyst for the degradation of rhodamine B

A magnetic chitosan/TiO₂ composite material (MCT) was developed. MCT was successfully synthesized by a one-pot method using chitosan, TiO₂, and Fe₃O₄. The absorption equilibrium time of MCT was 40 min in absorbing vanadium(v), the optimal adsorption pH was 4, and the maximum adsorption capacity of vanadium(v) was 117.1 mg g^-1. The spent MCT was applied to photocatalytic reactions for reutilization. The decolorization rates for the degradation of rhodamine B (RhB) by new and spent MCT were 86.4% and 94.3%, respectively. The new and spent MCT exhibited absorption bands at 397 and 455 nm, respectively, which showed that the spent MCT was red-shifted to the cyan light region. These results indicated that the forbidden band widths of the new and spent MCT were about 3.12 and 2.72 eV, respectively. The mechanism of the degradation reaction showed that the hydroxyl radicals as oxidants in the spent MCT mediated the photocatalytic degradation of RhB. In addition, the superoxide anion radical formation of hydroxyl radicals was the main reaction, and the hole generation of hydroxyl radicals was the subordinate reaction. The N-de-ethylated intermediates and organic acids were monitored by MS and HPLC.

Synthesis process and adsorption performance of temperature-sensitive ion-imprinted porous microspheres (ReO4−-TIIM) for the selective separation of ReO4−

The adsorption–desorption process of imprinted microspheres is controlled by changing the temperature conditions of the external environment.

Selective identification and separation of ReO4- by biomimetic flexible temperature-sensitive imprinted composite membranes

A new type of temperature-sensitive imprinted composite membranes(ICMs) was developed. Poly N,N-diethylacrylamide (DEA) blocks, as temperature-sensitive polymer, were grafted onto the substrate of the imprinted polymer separation layer to endow membranes with better adsorption effect. The comprehensive properties of the imprinted composite membranes were adequately tested and evaluated in detail. Results showed that ReO₄^- -ICMs (Re-ICMs) with temperature-sensitive recognition sites could adjust the structure of the imprinted holes at different temperatures, which presented excellent performance in the selective separation and purification of ReO₄^-. The prepared Re-ICMs exhibit the maximum adsorption capacity of 0.1639 mmol/g at 35 °C with the equilibrium adsorption time of 2 h. After ten adsorption/desorption cycles, Re-ICMs could still maintain 73.5% of the original adsorption capacity, the separation degree of ReO₄^-/MnO₄^- was only reduced from the initial 24.5 to 15.9, and the desorption ratio dropped from 80.4% to 68.4%, indicating that Re-ICMs have excellent adsorption and separation performance and reusability.

Study on Synthesis and Adsorption Properties of ReO4 - Ion-Imprinted Polymer

In this work, an ion imprinted polymer (ReO₄ ^--IIP) of the perrhenate ion based on acrylamide (AM) and acrylic acid (AA) was prepared by solution polymerization using ReO₄ ^- as a template ion, N,N-methylenebisacrylamide (NMBA) as cross-linkers, hydrogen peroxide-vitamin C (H₂O₂-Vc) as an initiator, and a mixed solution of water (H₂O) and methanol (CH₃OH) with volume ratio v(H₂O)/v(CH₃OH) = 3:7 as a solvent. During the process of synthesis condition investigation and optimization, the adsorption capacity (Q) and the separation degree (R) in the equimolar concentration mixture solutions of NH₄ReO₄ and KMnO₄ were adopted as indexes, and the obtained optimal conditions were as follows: the molar ratios of NMBA, NH₄ReO₄, AA, H₂O₂, and Vc to AM were 5.73, 0.052, 1.29, 0.02, and 0.003, and the temperature and time of polymerization were 40 °C and 28 h, respectively. Under optimal conditions, the sample with indexes, Q and R of 0.064 mmol/g and 3.20, were harvested. What is more, a further reusability study found that good adsorption selectivity was maintained after repeating the experiment 9 times. Taking the non-IP prepared under the same conditions as a control, Fourier transform infrared spectroscopy, transmission electron microscopy, and Brunauer Emmett Teller were used to characterize the structure of the ReO₄ ^--IIP prepared under the optimal conditions. Finally, the kinetic study results showed that the zero-order kinetic model could better describe the adsorption process. The thermodynamic study results showed that the Langmuir model was more suitable for describing the isotherm adsorption process of the IIP.