Selective, highly efficient extraction of Cr(III), Pb(II) and Fe(III) from complex water environment with a tea residue derived porous gel adsorbent

• Published in: Bioresource technology Vol. 311; p. 123520
• Main Authors: Zhang, Shuaizhong, Liu, Chengzhen, Yuan, Yongkai, Fan, Minghao, Zhang, Dandan, Wang, Dongfeng, Xu, Ying
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.09.2020
• Subjects: Adsorption Mechanism; Fixed-Bed Column; Hydrogel; Tea Residue; Hydrogel; Adsorption Mechanism; Tea Residue; Fixed-Bed Column
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2020.123520

[Display omitted] •A novel gel adsorbent based on tea residue was successfully synthesized.•The gel showed selectivity, ultrafast dynamics for Pb(II), Cr(III), and Fe(III).•Tea residue and acrylic composite structure played a key role in adsorption.•The fixed bed column is used to treat wastewater with high efficiency. A novel macroporous (~150 μm) double network hydrogel (TR/PAA) was prepared from tea residue and acrylic acid, and its performance was systematically evaluated. The static adsorption experiments showed that gel exhibited high selectivity and adsorption capacity, ultrafast kinetics (~10 min) for Cr(III), Pb(II) and Fe(III). The adsorption behavior showed heterogeneous and chemisorption process adsorption capacities of 206.19, 253.16, and 94.88 mg g−1 for Cr(III), Pb(II) and Fe(III), respectively. In pluralistic systems, TR/PAA showed the adsorption order of Fe(III) > Cr(III) > Pb(II). Mechanism studies confirm that nitrogen and oxygen-containing functional groups play a major role in the adsorption process. In the fixed-bed column experiments, the treatment volume of simulated wastewater reached 1400 bed volumes (BV) (21.6 L), producing only 7 BV (323 mL) eluent. This work provides a new avenue for the combination of TR/PAA reuse and heavy metal removal, which is expected to be applied in actual wastewater treatment.