Preparation of Integrated Oxygen Permeable Membranes with a Porous Layer by Partial Reduction Process

Abstract

An oxygen permeable membrane based on mixed oxide-ion and electronic conduction is a promising material for hydrogen production from methane at high temperatures. To increase an oxygen permeation flux, decreasing in thickness is required. In this study, integrated oxygen permeable membranes supported on a porous layer was prepared by partial reduction of dense composite materials. The dense samples of (ZrO 2 -3 mol%Y 2 O 3 )-x vol%NiFe 2 O 4 (x = 33,40,50) were prepared by sintering at 1400°C under air for 5 h. The one side of the sample was reduced at a temperature range of 800 to 1000°C under Ar-5%H 2 . The microstructure and oxygen flux density were analyzed by using a scanning electron microscopy and a quadrupole mass spectroscopy, respectively. An integrated oxygen permeable membrane of (ZrO 2 -3 mol%Y 2 O 3 )-50 vol%NiFe 2 O 4 having a dense layer of 200 μm and a porous layer of 300 μm was successfully prepared. The oxygen flux density of the membrane was found to be 4.3―7.4 x 10 ―7 mol·cm ―2 ·s ― 1 .