Gao Jing, Dong Chen, Zhao Yunting, Ma Tian, He Yongjun
Department of Chemistry and Chemical Engineering, Xi'an University of Science and Technology, 58 Yanta Middle Road, Beilin District, Xi'an, China E-mail:
Water Sci Technol. 2023 Jan;87(2):454-468. doi: 10.2166/wst.2022.430.
Traditional liquid-solid extraction methods for the removal of zinc ions (Zn(II)) were generally limited by the leakage of extractant and low extraction capacity. The two-component Pickering emulsion hydrogels (PEHGs) in which the synergistic 2-ethylhexyl hydrogen-2-ethylhexylphosphate/tributyl phosphate (EHEHPA/TBP) was encapsulated in a semi-penetrating polymer network (SIPN) structured hydrogels polyacrylamide/sodium alginate (PAM/SA) were prepared by the Pickering emulsions polymerization route. The PEHGs were characterized by FTIR, SEM, TGA, and tensile mechanical measurements, and their self-healing properties were explored. The adsorption performance of PEHGs on Zn(II) was investigated. The results showed that the encapsulation of the extractant reached 95% due to the hydrogels network and nano-silica (nano-SiO) particle network in PEHGs-15. The critical crashing pressure of PEHGs-15 was 0.084 MPa, and the adsorption after 3 h of healing was only 86% of the original amount. The maximum adsorption capacity of PEHGs-15 on Zn(II) was 76.51 mg/g at pH 5. The functional groups of SA and EHEHPA/TBP enhanced the adsorption capacity of PEHGs-15 by chelating with Zn(II). After five adsorption-desorption cycles, the adsorption capacity of PEHGs-15 exceeded 85% of the initial one. The excellent mechanical properties, self-healing, and regenerative properties of PEHGs-15 offer the potential to remove Zn(II) from the solution.
传统的用于去除锌离子（Zn(II)）的液固萃取方法通常受到萃取剂泄漏和萃取能力低的限制。通过Pickering乳液聚合法制备了双组分Pickering乳液水凝胶（PEHG），其中协同的2-乙基己基磷酸2-乙基己酯/磷酸三丁酯（EHEHPA/TBP）被包裹在半互穿聚合物网络（SIPN）结构的水凝胶聚丙烯酰胺/海藻酸钠（PAM/SA）中。通过FTIR、SEM、TGA和拉伸力学测量对PEHG进行了表征，并探索了它们的自愈性能。研究了PEHG对Zn(II)的吸附性能。结果表明，由于PEHGs-15中的水凝胶网络和纳米二氧化硅（nano-SiO）颗粒网络，萃取剂的包封率达到了95%。PEHGs-15的临界破碎压力为0.084 MPa，愈合3 h后的吸附量仅为原始量的86%。在pH值为5时，PEHGs-15对Zn(II)的最大吸附容量为76.51 mg/g。SA和EHEHPA/TBP的官能团通过与Zn(II)螯合提高了PEHGs-15的吸附容量。经过五次吸附-解吸循环后，PEHGs-15的吸附容量超过了初始值的85%。PEHGs-15优异的机械性能、自愈性能和再生性能为从溶液中去除Zn(II)提供了潜力。
