Chemical Identification and Organoleptic Evaluation of Iodine and Iodinated Disinfection By-Products Associated with Treated Spacecraft Drinking Water

Aboard the International Space Station, potable water will likely be produced from recycled wastewater. The National Aeronautic and Space Administration (NASA) plans to use iodine as a disinfectant, and, consequently, the formation of iodinated disinfection by-products (IDBPs) requires investigation. Objectives of this research were to determine possible precursors of IDBPs, identify IDBPs formed, and apply flavor profile analysis (FPA) as a tool to evaluate water qaulity. Experiments were performed by separately reacting iodine with each of the following organic compounds: methanol, ethanol, 1-propanol, 2-propanol, 1-methoxy-2-propanol, acetone, and formaldehyde. NASA previously identified all of these compounds in wastewater sources under consideration for recycling into potable water. Experiments were performed at pH 5.5 and 8, iodine concentrations of 10 and 50 mg/L, and organic concentrations of 5 and 50 mg/L. Gas chromatography/mass spectrometry was used to identify and monitor the concentrations of organic species. Spectrophotometry was used to monitor the iodine concentration. Acetone was the only compound identified as an IDBP precursor and it reacted to produce iodoacetone and iodoform. Concentrations of iodoform from 0.34 mg/L to 8.637 mg/L were produced at conditions that included each pH level, iodine concentration, and acetone concentration. The greatest iodoform concentration was produced at pH 8 from 50 mg/L of iodine and acetone. FPA indicated that the odor threshold concentration (OTC) of iodoform was 1.5 ug/L, and the OTC of iodine was 500 ug/L. Both iodine and iodoform have medicinal odors, making it difficult to distinguish each compound when present in a mixture.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Civil Engineering

Department dc:contributor.department

Civil Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1997

Author dc:creator

• Dodd, Jennifer Peters

Chair dc:contributor.committeechair

• Dietrich, Andrea M.

Committee members dc:contributor.committeemember

• Hoehn, Robert C.
• Gallagher, Daniel L.

• flavor profile analysis
• iodoform
• iodine
• disinfection by-product

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

etd-34521672975650

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/36642