Hollow polyphosphazene microcapsule with rigid-flexible coupling cationic skeletons for highly efficient and selective adsorption of anionic dyes from water

作者：Zhang, Xiaofan; Hou, Lumiao; Liu, Haowei; Chang, Limin; Lv, Shen; Niu, Bolin; Zheng, Jianwei^*; Liu, Shaohua; Fu, Jianwei^*

来源：Applied Surface Science, 2023, 626: 157234.

DOI：10.1016/j.apsusc.2023.157234

• Polymer
• Microcapsule
• Selective adsorption
• Dye
• Microstructure

An amino-rich hollow polyphosphazene microcapsule with rigid-flexible coupling cationic skeleton (HTCM) was facilely prepared by one-step polycondensation from hexachlorocyclotriphosphazene and tetraethylenepent-amine. The systematic adsorption studies for six single dye systems and three binary mixed dye systems showed that HTCM possessed a highly-efficient and selective adsorption behavior towards anionic dyes from water. Especially, the adsorption capacity of HTCM towards methyl orange (MO) at equilibrium reached 1009.66 mg g-1 at 25 degrees C, and the relative separation factors of anionic dye MO for three cationic dyes (methylene blue, Crystal violet and Rhodamine B) was up to 124.22, 124.87 and 136.35, respectively. The adsorption rate of MO onto HTCM was very rapid, attaining 68.6 % of adsorption equilibrium capacity for MO within the first 30 min. The adsorption kinetics, isotherm and thermodynamic analysis revealed that the uptake behavior of HTCM to-wards MO obeyed pseudo-second-order kinetic model, intraparticle diffusion model and Langmuir model, and the uptake process was spontaneous and endothermic. As verified from FT-IR and XPS analysis for HTCM before and after MO adsorption, the adsorption mechanism of HTCM for MO involved electrostatic interaction and hydrogen bonding. The present study promises the potential of HTCM for highly selective separation of anionic dyes from wastewater.

• 单位
  郑州大学; 华中科技大学