Abstract
Poly((3-Acrylamidopropyl)trimethylammonium chloride) (p(APTMACl)) cryogels were used as a superporous polymer network for the removal of toxic arsenate anions from an aqueous medium. The fast swelling in water, in about 7 s, was shown to be very useful leading to fast arsenate adsorption by p(APTMACl) cryogels within 30 min in comparison to 12 h for bulk common p(APTMACl) hydrogels. A maximum adsorption capacity of about 120 (mg/g) arsenate was obtained for p(APTMACl) cryogels. Both the Langmuir and Freundlich adsorption isotherms were applied for adsorption of arsenate anions by p(APTMACl) cryogels, and it was observed that the adsorption of arsenate anions by p(APTMACl) cryogels are represented better via Langmuir adsorption isotherm providing the R2 value of 0.998. Furthermore, mag-p(APTMACl) cryogels were synthesized, and shown to be very useful in the fast removal of toxic arsenate anions. The mag-p(APTMACl) cryogels including the adsorbed arsenate were removed by an externally applied magnetic field, with some reduction in the arsenate ion adsorption capacity. It was also further demonstrated that p(APTMACl) cryogels can be reused in the adsorption of arsenate 5 times from aqueous environments without significant loss of adsorption capacity, from 113.47 ± 9 to 102.67 ± 6 mg/g.
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•P(APTMACl) cryogel with 10–100 μm pores are prepared in cryogenic conditions.•Superporous p(APTMACl) cryogel showed fast swelling ability in water.•Superporous p(APTMACl) cryogel adsorbed about 118 mg/g arsenate in about 2 h.•Magnetic p(APTMACl) cryogels can be used for fast arsenic removal in seawater.