Preparation and Oxygen Permeation of La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) Perovskite-Type Membranes: Experimental Study and Mathematical Modeling

Autor: Toraj Mohammadi, Amir Atabak Asadi, Mona Iravaninia, Amir Behrouzifar, Afshin Pak
Rok vydání: 2012
Předmět:
Zdroj: Industrial & Engineering Chemistry Research. 51:3069-3080
ISSN: 1520-5045
0888-5885
Popis: La0.6Sr0.4Co0.2Fe0.8O3−δ nanopowder, synthesized via an autocombustion technique, was pressed into disk-shaped membranes. Results of permeation experiments revealed that oxygen permeation flux increases as temperature, feed side oxygen partial pressure, and feed and sweep gas flow rates increase, while it decreases with membrane thickness and permeate side oxygen partial pressure. A Nernst–Planck based mathematical model, including surface exchange kinetics and bulk diffusion, was developed to predict oxygen permeation flux. Considering nonelementary surface reactions and introducing system hydrodynamics into the model resulted in an excellent agreement (RMSD = 0.0344, AAD = 0.0274 and R2 = 0.9960) between predicted and measured fluxes. Feed side surface exchange reactions, bulk diffusion, and permeate side surface exchange reaction resistances are in the range of Rex′ = 7 × 103 to 9 × 106, Rdiff = 1 × 105 to 2 × 107, and Rex″ = 1 × 104 to 2 × 107 (s/m), respectively. The permeation rate-limiting step was...
Databáze: OpenAIRE