title: Structure regulation of silica nanotubes and their adsorption behaviors for heavy metal ions: pH effect, kinetics, isotherms and mechanism.
abstract: Silica nanotubes (SNTs) with controlled nanotubular structure were synthesized via an electrospinning and calcination process. In this regard, SNTs were found to be ideal adsorbents for Pb(II) removal with a higher adsorption capacity, and surface modification of the SNTs by sym-diphenylcarbazide (SD-SNTs) markedly enhanced the adsorption ability due to the chelating interaction between imino groups and Pb(II). The pH effect, kinetics, isotherms and adsorption mechanism of SNTs and SD-SNTs on Pb(II) adsorption were investigated and discussed detailedly. The adsorption capacity for Pb(II) removal was found to be significantly improved with the decrease of pH value. The Langmuir adsorption model agreed well with the experimental data. As for kinetic study, the adsorption onto SNTs and SD-SNTs could be fitted to pseudo-first-order and pseudo-second-order model, respectively. In addition, the as-prepared SNTs and SD-SNTs also exhibit high adsorption ability for Cd(II) and Co(II). The experimental results demonstrate that the SNTs and SD-SNTs are potential adsorbents and can be used effectively for the treatment of heavy-metal-ions-containing wastewater.
authors.affiliation: College of Materials and Textiles, Zhejiang Sci-Tech University, Hangzhou 310018, PR China.
authors.forename: Pan
authors.initials: P
authors.lastname: Wang
authors.affiliation: College of Materials and Textiles, Zhejiang Sci-Tech University, Hangzhou 310018, PR China; Key Laboratory of Advanced Textile Materials and Manufacturing Technology, Zhejiang Sci-Tech University, Ministry of Education, Hangzhou 310018, PR China. Electronic address: du@zstu.edu.cn.
authors.forename: Mingliang
authors.initials: M
authors.lastname: Du
authors.affiliation: College of Materials and Textiles, Zhejiang Sci-Tech University, Hangzhou 310018, PR China.
authors.forename: Han
authors.initials: H
authors.lastname: Zhu
authors.affiliation: College of Materials and Textiles, Zhejiang Sci-Tech University, Hangzhou 310018, PR China.
authors.forename: Shiyong
authors.initials: S
authors.lastname: Bao
authors.affiliation: College of Materials and Textiles, Zhejiang Sci-Tech University, Hangzhou 310018, PR China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Yang
authors.affiliation: College of Materials and Textiles, Zhejiang Sci-Tech University, Hangzhou 310018, PR China.
authors.forename: Meiling
authors.initials: M
authors.lastname: Zou
mesh_terms: D000327:Adsorption; D002104:Cadmium / Q000737:chemistry*; D003035:Cobalt / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D007854:Lead / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D012822:Silicon Dioxide / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods
chemical_list: D014874:Water Pollutants, Chemical; D002104:Cadmium; D007854:Lead; D003035:Cobalt; D012822:Silicon Dioxide
keywords: Adsorption; Heavy metal ions; Pb(II); Silica nanotubes (SNTs); Structure regulation