{"title":"Fabrication of Kaolin Loaded Chitosan Hybrid Nanofibers for Recovery of Precious Palladium Cations from Aqueous Solution","authors":"Yaqing Liu, Yixin Cui, Huibiao Meng, Ke Long, Linjun Shao, Guiying Xing","doi":"10.1007/s10924-024-03395-2","DOIUrl":null,"url":null,"abstract":"<p>Palladium plays an important role in modern industry, agriculture and medicine. The direct discharge of palladium results in serious environmental pollution and loses of precious palladium metal. Herein, kaolin/chitosan hybrid nanofibers were successfully prepared to recover Pd<sup>2+</sup> cations from aqueous solution. Chitosan and kaolin mixture was first electrospun into nanofibers with citric acid as the in situ crosslinking agent and poly(ethylene oxide) as the co-spinning polymer. Then, the chitosan molecules in these hybrid nanofibers were in situ crosslinked by critic acid at elevated temperatures to endow these nanofibers with excellent solvent resistance. Their structure characterization was conducted by Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and positron annihilation lifetime spectroscopy (PLAS). The adsorption performances of these fibrous adsorbents were carefully investigated and optimized (e.g. kaolin content, temperature, pH of solution and initial Pd<sup>2+</sup> concentration). The adsorption results demonstrated that incorporation of kaolin powders into the nanofibers could enhance the adsorption capacity from 31 mg/g to 64 mg/g. Thermodynamic parameters studies revealed the endothermic and spontaneous natures of the adsorption process of Pd<sup>2+</sup> cations on these hybrid nanofibers. The Pd<sup>2+</sup> adsorption behavior of this fibrous adsorbent fitted well with the second-order kinetic model, suggesting the chemical adsorption behavior of Pd<sup>2+</sup> cations on this fibrous adsorbent. Moreover, this fibrous adsorbent can be easily regenerated and reused at least three times without significant loss of initial adsorption capacities. These results clearly indicate that this fibrous chitosan/kaolin hybrid absorbent holds great potential in the recovery of precious palladium cations from aqueous solution.</p>","PeriodicalId":659,"journal":{"name":"Journal of Polymers and the Environment","volume":null,"pages":null},"PeriodicalIF":4.7000,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Polymers and the Environment","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1007/s10924-024-03395-2","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, ENVIRONMENTAL","Score":null,"Total":0}
引用次数: 0
Abstract
Palladium plays an important role in modern industry, agriculture and medicine. The direct discharge of palladium results in serious environmental pollution and loses of precious palladium metal. Herein, kaolin/chitosan hybrid nanofibers were successfully prepared to recover Pd2+ cations from aqueous solution. Chitosan and kaolin mixture was first electrospun into nanofibers with citric acid as the in situ crosslinking agent and poly(ethylene oxide) as the co-spinning polymer. Then, the chitosan molecules in these hybrid nanofibers were in situ crosslinked by critic acid at elevated temperatures to endow these nanofibers with excellent solvent resistance. Their structure characterization was conducted by Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and positron annihilation lifetime spectroscopy (PLAS). The adsorption performances of these fibrous adsorbents were carefully investigated and optimized (e.g. kaolin content, temperature, pH of solution and initial Pd2+ concentration). The adsorption results demonstrated that incorporation of kaolin powders into the nanofibers could enhance the adsorption capacity from 31 mg/g to 64 mg/g. Thermodynamic parameters studies revealed the endothermic and spontaneous natures of the adsorption process of Pd2+ cations on these hybrid nanofibers. The Pd2+ adsorption behavior of this fibrous adsorbent fitted well with the second-order kinetic model, suggesting the chemical adsorption behavior of Pd2+ cations on this fibrous adsorbent. Moreover, this fibrous adsorbent can be easily regenerated and reused at least three times without significant loss of initial adsorption capacities. These results clearly indicate that this fibrous chitosan/kaolin hybrid absorbent holds great potential in the recovery of precious palladium cations from aqueous solution.
期刊介绍:
The Journal of Polymers and the Environment fills the need for an international forum in this diverse and rapidly expanding field. The journal serves a crucial role for the publication of information from a wide range of disciplines and is a central outlet for the publication of high-quality peer-reviewed original papers, review articles and short communications. The journal is intentionally interdisciplinary in regard to contributions and covers the following subjects - polymers, environmentally degradable polymers, and degradation pathways: biological, photochemical, oxidative and hydrolytic; new environmental materials: derived by chemical and biosynthetic routes; environmental blends and composites; developments in processing and reactive processing of environmental polymers; characterization of environmental materials: mechanical, physical, thermal, rheological, morphological, and others; recyclable polymers and plastics recycling environmental testing: in-laboratory simulations, outdoor exposures, and standardization of methodologies; environmental fate: end products and intermediates of biodegradation; microbiology and enzymology of polymer biodegradation; solid-waste management and public legislation specific to environmental polymers; and other related topics.