Search

Achieving both rapid adsorption rate and high adsorption capacity for bisphenol micropollutants from aquatic systems is critical for efficient adsorbents in water remediation. Here, we elaborately prepared three nitrogen-rich triazine-based porous polymers (NTPs) with similar geometric configurations and nitrogen contents (41.70–44.18 wt%) while tunable BET surface areas and micropore volumes in the range of 454.7–536.3 m2 g−1 and 0.20–0.84 cm3 g−1, respectively. It was systematically revealed that the synergy of hydrogen bonding, π−π electron-donor-acceptor interaction, and micropore preservation promoted the rapid (within 5 min) and high capacity adsorption of bisphenols by NTPs. Particularly, microporous-dominated NTPs-3 with the highest micro-pore volume (0.84 cm3 g−1) displays remarkable adsorption capacity towards bisphenol A as evidenced by the adsorption capacity of 182.23 mg g−1. A simple column filter constructed by NTPs-3 also expressed good dynamic adsorption and regeneration capacity. This work provided new insight into the rational design and engineering of nitrogen-rich porous polymers for the remediation of micropollutant wastewater. Three nitrogen-rich triazine-based porous polymers with similar geometric configurations and nitrogen contents while tunable BET surface areas and micropore volumes were used for the adsorption of bisphenol micropollutants. [Display omitted] • NTPs have similar geometric configurations and nitrogen contents while tunable porosities. • The adsorption mechanism is the synergy of hydrogen bonding, π−π interaction, and micropore preservation. • NTPs-3 expressed rapid and high capacity adsorption of bisphenols. • A simple column filter constructed by NTPs expressed good dynamic adsorption and regeneration capacity. [ABSTRACT FROM AUTHOR]

Efficient adsorption of organic dyes from effluent has great importance for ecological and environmental protection. Herein, covalent triazine frameworks (CTFs) were constructed via the polycondensation of melamine and cyanuric chloride directly. Due to the numerous basic nitrogen atoms as high as 58.98 wt%, high BET surface area (670.2 m g−1), and hierarchical pore structure, CTFs demonstrated selective adsorption of anionic dyes in high capacity (e.g., a maximum adsorption capacity of 1581 mg g−1 for Congo red at 30 °C). The mechanism of the outstanding adsorption performance was carefully verified and ascribed to the electrostatic attraction and hydrogen bonding between CTFs and anionic dyes. The amine groups linking two adjacent triazine rings have primary responsibility for the superior performance. Unexpectedly, CTFs expressed a tuning synergetic effect for removing cationic dyes in aqueous solution coexisting with anionic dyes, exhibiting a great superiority in the specific and comprehensive treatment of organic dyes contaminated water. Furthermore, CTFs were stable and had long-periodic availability for more than 6 times, ensuring the adsorption rate higher than 90%. For better operation, hybrid monolithic aerogels were constructed by incorporating CTFs into polyvinylidene fluoride then casting in melamine resin foams. The obtained aerogels expressed high-efficient removal of anionic dyes coupled with convenient operation. This well-established metal-free porous material is a promising adsorbent candidate for anionic dyes selectively and even synergetic adsorption of cationic dyes in water remediation. [Display omitted] • Covalent triazine frameworks with numerous nitrogen atoms, high BET surface area, and hierarchical pore structure were constructed. • CTFs had selective adsorption of anionic dyes in high capacity. • The adsorption mechanism was verified to be electrostatic attraction and hydrogen bonding. • The amine groups (-NH-) in CTFs have primary responsibility for the superior adsorption performance. • CTFs expressed a tuning synergetic effect for removing cationic dyes coexisting with anionic dyes. [ABSTRACT FROM AUTHOR]