Investigation of Ion Transport Mechanisms in NAFION in the Presence of Water and Methanol

Abstract

The electrical conductivity of NAFION membranes in various methanol/water solutions was measured. The conductivity measurements were conducted at frequencies between 100 Hz and 40 MHZ while the membrane was at room temperature and atmospheric pressure. The membranes absorbed different amounts of each solution by either soaking in the solution, being suspended over the solution, or being given a small amount of solution to absorb while in a closed tube. Generally, it was found that membranes with a high methanol fraction did not have high conductivity. The highest conductivity was found in pure water samples. This led to the conclusion that at these concentrations, methanol does not significantly affect the conductivity of protons but does pass through the membrane. Solutions with a small amount of methanol appeared to be absorbed more by the membrane than did pure water. This may be due to the larger mass of the methanol molecule. The large amount of methanol absorbed by NAFION in this experiment is indicative of methanol crossover.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1996
Accession Number
ADA375694

Entities

People

  • Jennifer R. Mills

Organizations

  • United States Naval Academy

Tags

Communities of Interest

  • Advanced Electronics
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Alcohol Fuels
  • Alcohols
  • Chemical Reactions
  • Combustion
  • Conductivity
  • Efficiency
  • Frequency
  • Fuel Cells
  • Heat Engines
  • Impedance
  • Internal Combustion Engines
  • Measurement
  • Molecular Weight
  • Molecules
  • Transport Ships
  • United States Naval Academy
  • Vehicles

Readers

  • Environmental Engineering
  • Mathematics or Statistics
  • Organic Chemistry