Eco-Friendly Phosphorus and Nitrogen-Rich Inorganic–Organic Hybrid Hypercross-linked Porous Polymers via a Low-Cost Strategy

ACS Appl. Polym. Mater.

et al. 2022

The development of porous organic polymers with high gas adsorption and separation performances by a facile preparation process has progressively addressed the urgent demand for cost-effective adsorbents employed in energy-efficient purification and recovery processes. However, these polymeric materials are still poorly developed for the practical adsorption and separation of light C1–C3 hydrocarbon components, such as methane (CH4), ethane (C2H6), and propane (C3H8), from natural gas under ambient conditions. The present work addresses this issue by reporting the facile preparation of two triphenylamine-based nanoporous organic polymers (ANOPs), ANOP-M and ANOP-A, via acid-catalyzed Friedel–Crafts hydroxyalkylation polymerization using commercially available triphenylamine with tetrakis(4-formylphenyl)methane and 1,3,5,7-tetrakis(4′-formylphenyl)adamantane monomers, respectively. The specific surface areas of the ANOPs vary from 1052 to 1272 m2/g, with average pore sizes of 1.36 nm. Furthermore, the ANOP networks are demonstrated to be highly interconnected. Interestingly, the ANOPs have different adsorption capacities toward different C1–C3 hydrocarbons (CH4, C2H6, and C3H8) and CO2 molecules, and ANOP-M shows the highest uptake of C3H8 (97.9 cm3/g) and C2H6 (64.6 cm3/g) among these gas molecules at 298 K and 1 bar. Analyses reveal that these differences depend greatly upon the physical parameters of the gas molecules (e.g., polarizability, critical temperature, and molecular size) and the porosity parameters of the ANOPs, as well as the affinity between the gases and the polymer skeleton. The adsorption selectivities of the ANOPs in conjunction with C3H8/CH4, C2H6/CH4, C3H8/C2H6, C3H8/CO2, C2H6/CO2, and CO2/CH4 gas mixtures also differ significantly and exhibit values of 151–164, 17.5–17.8, 6.16–6.43, 14.2–15.1, 2.93–3.17, and 4.35–4.70, respectively. Accordingly, the facile preparation and excellent light hydrocarbon adsorption and separation properties of the ANOPs make these materials highly promising for applications involving the adsorption/separation of C1–C3 light hydrocarbons and CO2 from natural gas under ambient conditions.

Section: ■ Results and Discussionmentioning

confidence: 96%

Facile Preparation of Triphenylamine-Based Nanoporous Organic Polymers for Adsorption/Separation of C₁–C₃ Hydrocarbons and CO₂ in Natural Gas

Xie

Wang

ACS Appl. Polym. Mater.

et al. 2022

“…The value of 3209 mg g ‒1 I 2 vapor uptake is less than those of the reported porous polymers, such as TTA‐FMTA‐COF(6110 mg g ‒1 , 350 K), [ 25 ] TTA‐FMTA‐COF(5070 mg g ‒1 , 350 K), [ 26 ] MeBID[3] (4950 mg g ‒1 , 348 K), [ 27 ] TTA‐TTB COF (4950 mg g ‒1 , 350 K), [ 28 ] i‐POP‐BPTM‐3(4150 mg g ‒1 , 350 K), [ 23 ] amorphous porous organic polymers (ADB‐S 342 mg g ‒1 , 348 K). [ 29 ] Moreover, the values are superior to those of other reported NOPs, as seen in Table S1 (Supporting Information), such as hyper cross‐linked polymers (HCP‐PNs, 1560–1900 mg g ‒1 , 353 K), [ 30 ] covalent triazine‐based framework (TTPBTA, 1640 mg g ‒1 , 350 K), [ 31 ] conjugated microporous polymers (SCMPs, 1880–2220 mg g ‒1 , 353 K), [ 32 ] and porous aromatic framework (PAF‐24, 2760 mg g ‒1 , 348 K). [ 33 ] Surprisingly, the I 2 vapor uptake order of ANOPs is in accordance with the CO 2 uptake order of ANOPs.…”

Section: Resultsmentioning

confidence: 99%

Facile Preparation of Cost‐Effective Triphenylamine‐Based Nanoporous Organic Polymers for CO₂, I₂, and Organic Solvents Capture

Macro Chemistry & Physics

Guo

Xie

et al. 2022

Seeking cost-effective construction of nanoporous organic polymers for CO 2 and I 2 capture and organic solvents adsorption remains challenging. Two triphenylamine-based nanoporous organic polymers, ANOP-1 and ANOP-2, have been prepared successfully by Friedel-Crafts (F-C) hydroxyalkylation from low-cost triphenylamine (TPA) with commercial terephthalaldehyde and isophthalaldehyde, respectively. The effect of isomers of phenyl dialdehydes on the structure of porous architecture is investigated. The as-prepared ANOPs exhibit a moderate uptake of CO 2 , I 2 , and organic solvents because of the electron-rich TPA unit and nanometer-scale pore size of <2 nm. These findings demonstrate that F-C hydroxyalkylation is a cost-effective strategy for producing large amounts of triphenylamine-enriched, high specific BET surface area materials to develop commercial organic materials for industrial use.

“…47 In addition, this value exceeded those of other reported NOPs, such as PANs (67.1−83.6 cm 3 /g), 1 sPIs (54.4−67.4 cm 3 /g), 42 PBOs (48.9−59.1 cm 3 /g), 48 and ANOPs (32.5−51.8 cm 3 / g). 32 Under ambient conditions, the CNOPs also exhibited high CO 2 uptakes of 64.7−71.0 cm 3 /g, which are higher than those by other NOPs, including HCP−PNs (19.3−29.5 cm 3 / g), 49 TPE−OAC−MA (47.0 cm 3 /g), 50 PANs (20.9−50.4 cm 3 /g), 51,52 and pTOC (28.4 cm 3 /g). 53 The high CO 2 adsorption capacities in CNOPs might be associated with the abundant carbazole units and large microporous structures.…”

Section: ■ Introductionmentioning

confidence: 99%

Friedel–Crafts Synthesis of Carbazole-Based Hierarchical Nanoporous Organic Polymers for Adsorption of Ethane, Carbon Dioxide, and Methane

Wei

et al. 2022

Ind. Eng. Chem. Res.

The Friedel–Crafts (FC) reaction is a prominent synthetic tool for rapidly constructing complex molecular frameworks, but syntheses of carbazole-based nanoporous organic polymers (CNOPs) via FC hydroxyalkylation are rare. Herein we report the acid-catalyzed FC hydroxyalkylation synthesis of two CNOP networks, prepared (using p-phthalaldehyde) from 1,3,5-tris(9-carbazolyl)benzene and tris[4-(9H-carbazol-9-yl)phenyl]amine. The specific surface areas of the CNOPs ranged from 1374 to 1546 m2/g, and the CNOPs had a hierarchical porous structure with pore sizes ranging from 0.87 to 6.60 nm. Furthermore, the high porosity in conjunction with abundant carbazole units in the CNOPs enabled excellent adsorption performance toward C2H6, CO2, and CH4. CNOP-2 derived from 1,3,5-tris(9-carbazolyl)benzene and p-phthalaldehyde displayed C2H6, CO2, and CH4 uptakes of up to 98.7, 90.2, and 30.7 cm3/g, respectively, at 1 bar and 273 K. Also, the adsorption selectivities of the CNOPs in conjunction with C2H6/CH4 and CO2/CH4 gas mixtures were 23.4–23.5 and 6.4–7.3, respectively. This work demonstrates a cost-effective FC reaction that can be used to design and construct carbazole-based nanoporous organic polymers.