Amorphous Porous Organic Polymers Based on Schiff‐Base Chemistry for Highly Efficient Iodine Capture

Abstract

Porous organic polymers (POPs) have been considered as prominent adsorbents for volatile iodine. So far, both crystalline and amorphous POPs have accomplished excellent iodine capture capability. Considering the difficulty and challenges in preparing perfect crystalline POPs, more explorations into developing versatile amorphous POPs are needed. Herein, amorphous POPs based on the Schiff-base reaction were designed and synthesized for volatile iodine removal. Four amorphous POPs products named as NDB-H, NDB-S, ADB-HS, and ADB-S obtained under different solvothermal conditions were investigated in terms of their morphologies, porosity, and their iodine enrichment performance in detail. It is noteworthy that excellent efficiency for removing iodine vapor was acquired for NDB-S (≈425 wt %), ADB-HS (≈345 wt %), and ADB-S (≈342 wt %). Remarkably, NDB-H exhibited an iodine capture capacity up to ≈443 wt %. Excellent reusability was obtained as well. Amorphous NDB-H has accomplished an extremely high iodine capture performance, illustrating the great chance to exploit versatile amorphous POPs for iodine enrichment and removal based on Schiff-base chemistry.

Improving iodine adsorption performance of porous organic polymers by rational decoration with nitrogen heterocycle

“…In the FTIR spectra (Figure 1(a), left), the vibrations at 1555, 1485, and 1334 cm −1 could be assigned to characteristic vibration of triazine rings, 34 while the peaks at 1670 and 3413 cm −1 to the stretching and bending vibrations of the N H bond of secondary amine, respectively. 35,36 The peak at 2920 cm −1 could be assigned to that of methylene (CH), 37 confirming the formation of NH CH NH linkage. In comparison with the FTIR spectra of reactant ( Figure S1), the peak at 1690 cm −1 corresponding to C O stretching vibration in Figure 1(a) disappears for all PAOPs, demonstrating the severe consumption of aldehyde groups.…”

Cationic Nonporous Macrocyclic Organic Compounds for Multimedia Iodine Capture

“…Most of the porous iodine adsorption materials have the advantage of high adsorption capacity. However, owing to the weak interactions between guest iodine molecules and porous host framework, adsorbed iodine in the channels will release rapidly when the iodine‐loaded materials are placed in methanol, ethanol and other organic solvents [18,27–30] . In fact, a large proportion of the porous materials are not suitable for long‐term storage of radioactive iodine.…”

“…However, owing to the weak interactions between guest iodine molecules and porous host framework, adsorbed iodine in the channels will release rapidly when the iodine-loaded materials are placed in methanol, ethanol and other organic solvents. [18,[27][28][29][30] In fact, a large proportion of the porous materials are not suitable for long-term storage of radioactive iodine. Therefore, how to reasonably design and synthesize the structure of adsorption materials to effectively enhanced interaction with iodine molecules while ensuring their adsorption capacity is one of the important challenges in this field.…”

The mechanochemical Friedel‐Crafts polymerization as a solvent‐free cross‐linking approach toward microporous polymers

“…Classically, the syntheses of POPs are accomplished by various solvent‐based approaches, which suffer from certain deficiencies 37–41 . In addition to the issues of rapid precipitation of the products and the need for solubilizing groups, either requiring expensive starting materials or additional synthesis steps, a severe drawback is the generated solvent waste and the accompanied environmental impact 42–47 …”