Fabrication of attapulgite-based dual responsive composite hydrogel and its efficient adsorption for methyl violet. Issue 10 (29th April 2022)

• Record Type: Journal Article
• Authors: Liu, Yi-xin; Zhong, Hui; Li, Xiao-rong; Bao, Zhuan-li; Cheng, Zhi-peng; Zhang, Yu-jie; Li, Chun-xiang
• Is Part Of: Environmental technology. Volume 43:Issue 10(2022)
• Page Start: 1480
• Page End: 1492
• Publication Date: 2022-04-29
• Subjects: Acrylic acid -- adsorption -- attapulgite -- composite hydrogel -- N-isopropylacrylamide; Environmental engineering -- Periodicals; Environmental protection -- Periodicals; 628.05
• DOI: 10.1080/09593330.2020.1838623
• Languages: English
• ISSNs: 0959-3330

Abstract

ABSTRACT: In this work, attapulgite (ATP)-based dual sensitive poly (N-isopropylacrylamide-co-acrylic acid) composite hydrogel, P(NIPAM-co-AA)/ATP, was prepared by free radical polymerization. The prepared composite hydrogel was characterized via methods of scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), zeta potential analysis and Brunauer, Emmett, and Teller (BET) etc. The composite hydrogel showed pH and temperature sensitive behaviour, with lower critical solution temperature (LCST) of 35°C and highest swelling occurred at pH 8.0. The adsorption of methyl violet (MV) can be controlled by the hydrogel responsiveness, and 95.78% of MV can be removed at pH 8.0 and 35°C. The addition of a small amount of ATP (3 Wt%) can improve the swelling ratio and adsorption capacity. Kinetic analysis demonstrated that the experimental data were best fitted to the pseudo-second order model. Isotherm analysis showed that the equilibrium data followed Langmuir model with the adsorption capacity of 168.35 mg g −1 . In addition, the composite hydrogel has high adsorption selectivity for cationic dyes, and MV-loaded hydrogel is easy to regenerate, which can be used for successive adsorption cycles. These results demonstrate that the composite hydrogel has potential application in dye wastewater treatment. GRAPHICAL ABSTRACT: UF0001