Superadsorbent hydrogel based on lignin and montmorillonite for Cu(II) ions removal from aqueous solution

• Published in: International journal of biological macromolecules Vol. 127; pp. 511 - 519
• Main Authors: Sun, Xiao-Feng, Hao, Yiwei, Cao, Yingyue, Zeng, Qihang
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.04.2019
• Subjects: Adsorption; Cu(II) ion; Lignin; Montmorillonite; Superadsorbent; Lignin; Superadsorbent; Cu(II) ion; Montmorillonite; Adsorption
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2019.01.058

Superadsorbent hydrogel was prepared from lignin and montmorillonite for Cu(II) ions removal, and the chemical structure and morphology of the hydrogel were characterized by FT-IR, XRD, SEM and XPS. The swelling kinetics of the prepared hydrogel was investigated, and the result showed that the swelling process fit the Schott second-order dynamic equation. The influences of pH, contact time, Na+ concentration, and initial Cu(II) ion concentration on adsorption were studied, and the maximum adsorption value was 1.17 mmol/g, and the adsorption was rapid during the initial 5 h period, and copper ions adsorption on the superadsorbent hydrogel is a favorable process. The results also indicated that the adsorption kinetics was in accordance with the pseudo-second-order kinetic model and the adsorption isotherm conformed to the Freundlich model. FT-IR and XPS analysis revealed that the adsorption behavior was mainly due to ion exchange. The desorption ratios of copper ions from the superadsorbent were >0.8, and the regeneration efficiency was >80% after five cycles reuse, and the results show the excellent desorption performance and reusability of the prepared hydrogel.