Enhanced Cr(VI) removal by polyethylenimine- and phosphorus-codoped hierarchical porous carbons

Shixia Chen, Jun Wang, Zeliang Wu, Qiang Deng, Wenfeng Tu, Guiping Dai, Zheling Zeng, Shuguang Deng

Research output: Contribution to journalArticle

25 Scopus citations

Abstract

The amino- and phosphorus-codoped (N,P-codoped) porous carbons derived from oil-tea shells were facilely fabricated through a combination of phosphoric acid (H3PO4) activation and amino (polyethylenimine, PEI) modification method. The as-synthesized carbon adsorbents were systematically characterized and evaluated for Cr(VI) removal in aqueous solutions. The relationship between adsorbent properties and adsorption behaviors was illustrated. Moreover, the influences of contact time, initial Cr(VI) concentration, pH, coexisting anions and temperature were also investigated. The adsorption behavior of Cr(VI) could be perfectly described by the pseudo-second-order kinetic model and Sips adsorption model. The maximum adsorption capacity of Cr(VI) on the carbon adsorbents synthesized in this work was 355.0 mg/g, and this excellent Cr(VI) capacity could be sustained with other coexisting anions. In addition to high surface area and suitable pore size distribution, the high Cr(VI) removal capacity is induced by rich heteroatoms incorporation and the Cr(VI) removal mechanism was clearly illustrated. Furthermore, the continuous column breakthrough experiment on obtained N,P-codoped carbon was conducted and well fitted by the Thomas model. This work revealed that PEI modification and P-containing groups could significantly enhance Cr(VI) adsorption capacity and make these N,P-codoped biomass-derived carbons potent adsorbents in practical water treatment applications.

Original languageEnglish (US)
Pages (from-to)110-120
Number of pages11
JournalJournal of Colloid and Interface Science
Volume523
DOIs
StatePublished - Aug 1 2018

    Fingerprint

Keywords

  • Adsorption property
  • Hexavalentchromium
  • Phosphoric acid
  • Polyethylenimine
  • Porous carbon

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Surfaces, Coatings and Films
  • Colloid and Surface Chemistry

Cite this