Steady State Analysis of Water Transport through Sulfonated Polyether Ether Ketone (SPEEK) Membrane for Fuel Cell Application

Sulfonated Polyether Ether Ketone (SPEEK) membrane is considered as a potential alternative membrane for fuel cell because of its cost effectiveness and easily prepared. SPEEK membranes were prepared by solution casting method with film thickness of 80, 127 and 150 pm. Samples are analyzed by Fourier Transform Infrared (FTIR) Spectrometer. Water uptake study states that diffusivity of water increased with increase in Degree of Sulfonation (DS) of the membrane. Experimental moisture uptake data was fitted to a dual stage model. Proton conductivity of the membrane was measured by two probe method using impedance analyzer. Proton conductivity of the sample is improved with improving DS of membrane. Proton conductivity of membrane gave promising results in the range of 10(-2) to 10(-1) S/cm. Membrane water content has the greatest effect towards proton conductivity. The permeation of water through membrane was measured by in house permeation cell at a temperature range of 4090 degrees C and feed side water activity between 0.2 and 1. Water permeation from liquid feed increased with increase in membrane temperature and inversely proportional with membrane thickness. Water transported across the membrane in a permeation cell was considered as a one dimensional diffusion model. Water permeation data was compared with conventional Nafion permeation results. Water permeability data shows linear improvement with membrane water content and temperature.