Removal of copper ions using poly (acrylic acid-co-acrylamide) hydrogel microspheres with controllable size prepared by
- PDF / 1,198,673 Bytes
- 8 Pages / 595.276 x 790.866 pts Page_size
- 10 Downloads / 209 Views
ORIGINAL CONTRIBUTION
Removal of copper ions using poly (acrylic acid-co-acrylamide) hydrogel microspheres with controllable size prepared by W/O Pickering emulsions Songbai Yuan 1 & Kegong Ning 2 & Yongjun He 1 Received: 28 February 2020 / Revised: 16 July 2020 / Accepted: 27 July 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Poly (acrylic acid-co-acrylamide) hydrogel microspheres were prepared via Pickering emulsion polymerization with hydrophobic silica as emulsifiers. The functional groups and the morphology of the hydrogel microspheres were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. The effect of the dosage of hydrophobic silica on Pickering emulsion polymerization was investigated, and the hydrogel microspheres with different particle sizes were used to remove copper ions in water. The results showed that the diameter (D) of the hydrogel microspheres was inversely proportional to the dosage (S) of the hydrophobic silica used. The size of the hydrogel microspheres mainly affected the adsorption equilibrium time, and the maximum adsorption capacity could reach 85 mg/g at pH = 5. The results of desorption experiment demonstrated that copper ions were adsorbed by hydrogel microspheres mainly through chemical interaction. Pickering emulsion polymerization was an efficient and environmentally friendly approach for the fabrication of granular hydrogels. Keywords Pickering emulsions . Polymerization . Hydrogel microspheres . Adsorption
Introduction Having hydrophilic networks, hydrogels can be applied to adsorb metals and organic contaminants in wastewater [1]. In recent years, the synthesis of hydrogels has increasingly received attention, and varieties of hydrogels have been prepared from chitosan [2], alginate [3], amino acid [4], lignin [5], acrylamide [6], acrylic acid [7], and their composites [8–11]. The presence of the functional groups including −COOH, −NH2, −OH, −SO3H, and −CONH2 in flexible polymeric networks enables the hydrogels to remove heavy metal ions from wastewater [12–14]. Free radical polymerization in aqueous solution is a traditional method to synthesize bulk hydrogels [15, 16]. The bulk hydrogels often need to be * Kegong Ning [email protected] * Yongjun He [email protected] 1
Department of Applied Chemistry, Xi’an University of Science and Technology, Xi’an, China
2
Department of Health Products Technical Research & Development Center, Yunnan Baiyao Group Co. Ltd, Kunming, China
broken into small ones before using [17]. It is of great importance to explore an approach to obtain granular hydrogels during the polymerization. Emulsion polymerization is an ideal strategy to gain granular hydrogels in micrometer or nanometer size. Abdolbaghi et al. prepared poly (acrylamide)/nanoclay nanoparticles with average size of ∼ 250 nm via W/O Pickering emulsion polymerization [18]. Sobhanimatin et al. fabricated the microspheres based on acrylamide and 2-acrylamido-2methylpropane sulfonic acid with a size
Data Loading...
