Related Experiment Video
Updated: Jul 22, 2026
12:05
Preparation of Hydrophobic Metal-Organic Frameworks via Plasma Enhanced Chemical Vapor Deposition of Perfluoroalkanes for the Removal of Ammonia
Published on: October 10, 2013
"Reagentless" flow injection determination of ammonia and urea using membrane separation and solid phase basification
J R Akse1, J O Thompson, R L Sauer
1UMPQUA Research Company, Myrtle Creek, Oregon 97457, USA.
Summary
This study introduces a novel flow injection analysis method for determining ammonia and ammonium. The technique efficiently measures ammonia and ammonium in aqueous solutions with high sensitivity and a broad dynamic range.
Area of Science:
- Analytical Chemistry
- Environmental Science
Background:
- Accurate determination of ammonia and ammonium is crucial for environmental monitoring and water quality assessment.
- Existing methods may face challenges with speciation and sensitivity.
Purpose of the Study:
- To develop and validate a sensitive flow injection analysis (FIA) method for ammonia and ammonium determination.
- To extend the FIA method for urea analysis using enzymatic hydrolysis.
Main Methods:
- Utilized in-line solid-phase basification beds to shift ammoniacal nitrogen to the un-ionized form.
- Employed a hydrophobic microporous hollow fiber membrane for gas-phase diffusion of ammonia.
- Detected ammonium ions in the analytical stream via specific conductance measurement.
- Incorporated immobilized urease for enzymatic urea hydrolysis.
Main Results:
- Achieved a lower limit of detection of 10 µg/L for ammonia/ammonium.
- Demonstrated a dynamic concentration range spanning three orders of magnitude.
- Successfully extended the methodology for urea determination.
Conclusions:
- The developed FIA method offers a sensitive and robust approach for ammonia, ammonium, and urea analysis.
- The use of membrane separation and specific conductance detection provides reliable quantification in aqueous samples.
