Kinetics of nitrate adsorption and reduction by nano-scale zero valent iron (NZVI): Effect of ionic strength and initial pH

Do-Gun Kim, Yuhoon Hwang, Hang-Sik Shin, Seok-Oh Ko, Hang-Sik Shin, Seok-Oh Ko

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Kinetic models for pollutants reduction by Nano-scale Zero Valent Iron (NZVI) were tested in this study to gain a better understanding and description of the reaction. Adsorption kinetic models and a heterogeneous catalytic reaction kinetic equation were proposed for nitrate removal and for ammonia generation, respectively. A widely used pseudo-first-order reaction model was a poor fit for nitrate removal in an iron-limiting condition and for ammonia generation in an excess iron condition. However, in this study, pseudo-first-order and pseudo-second-order adsorption kinetic equations were a good fit for nitrate removal; in addition, a Langmuir-Hinshelwood kinetic equation was able to successfully describe ammonia generation, regardless of the NZVI dose, the ionic strength, and the initial pH. These results strongly indicate that nitrate reduction by NZVI is a heterogeneous catalytic reaction, and that that the kinetic models can be used in diverse conditions. The kinetic parameters correlate well with the reaction condition, unless the NZVI dose was greatly increased or unless the NZVI surface was significantly changed at a very high initial pH.
Original languageEnglish
JournalK S C E Journal of Civil Engineering
Volume20
Issue number1
Pages (from-to)175-187
ISSN1226-7988
DOIs
Publication statusPublished - 2016

Keywords

  • adsorption
  • heterogeneous catalytic reaction
  • ionic strength
  • kinetics
  • NZVI
  • pH
  • Adsorption
  • Ammonia
  • Catalysis
  • Enzyme kinetics
  • Integral equations
  • Iron
  • Kinetic energy
  • Kinetic parameters
  • Kinetic theory
  • Kinetics
  • Nanotechnology
  • Nitrates
  • Reaction kinetics
  • Surface morphology
  • Effect of ionic strength
  • Heterogeneous catalytic reactions
  • Langmuir-Hinshelwood kinetic equation
  • Nano-scale zero valent irons
  • Nitrate adsorptions
  • Pseudo second order
  • Pseudo-first order reactions
  • Ionic strength

Fingerprint Dive into the research topics of 'Kinetics of nitrate adsorption and reduction by nano-scale zero valent iron (NZVI): Effect of ionic strength and initial pH'. Together they form a unique fingerprint.

Cite this