Effect of humic acid on as redox transformation and kinetic adsorption onto iron oxide based adsorbent (IBA)

Hoda Fakour, Tsair Fuh Lin

Research output: Contribution to journalArticlepeer-review

15 Citations (Scopus)

Abstract

Due to the importance of adsorption kinetics and redox transformation of arsenic (As) during the adsorption process, the present study elucidated natural organic matter (NOM) effects on As adsorption-desorption kinetics and speciation transformation. The experimental procedures were conducted by examining interactions of arsenate and arsenite with different concentrations of humic acid (HA) as a model representative of NOM, in the presence of iron oxide based adsorbent (IBA), as a model solid surface in three environmentally relevant conditions, including the simultaneous adsorption of both As and HA onto IBA, HA adsorption onto As-presorbed IBA, and As adsorption onto HA-presorbed IBA. Experimental adsorption-desorption data were all fitted by original and modified Lagergren pseudo-first and -second order adsorption kinetic models, respectively. Weber’s intraparticle diffusion was also used to gain insight into the mechanisms and rate controlling steps, which the results suggested that intraparticle diffusion of As species onto IBA is the main rate-controlling step. Different concentrations of HA mediated the redox transformation of As species, with a higher oxidation ability than reduction. The overall results indicated the significant effect of organic matter on the adsorption kinetics and redox transformation of As species, and consequently, the fate, transport and mobility of As in different environmentally relevant conditions.

Original languageEnglish
Pages (from-to)10710-10736
Number of pages27
JournalInternational journal of environmental research and public health
Volume11
Issue number10
DOIs
Publication statusPublished - 2014 Oct 16

All Science Journal Classification (ASJC) codes

  • Pollution
  • Public Health, Environmental and Occupational Health
  • Health, Toxicology and Mutagenesis

Fingerprint

Dive into the research topics of 'Effect of humic acid on as redox transformation and kinetic adsorption onto iron oxide based adsorbent (IBA)'. Together they form a unique fingerprint.

Cite this