Oxygen permeation membranes

Since the turn of the millennium, there has been growing interest in oxygen permeation membranes due to their potential for use in industrial processes and commercial applications such as gas separation, commercial chemical reactions and solid oxide fuel cells. This chapter provides a brief review of the current state of research and development of oxygen permeation membranes that could play an important role in more efficient oxy-combustion processes. 

Brinkman, K., lijima, T., Takamura., H. (2007). Acceptor doped BiFeOa ceramics a new material for oxygen permeation membranes. Japanese Journal of Applied Physics, 46, L93. 

Properties and performance of A-site deficient (Bao,sSro,s)i Coo,8Feo,203 s for oxygen permeating membrane. /. Membr Sci., 306, 318-328. 

Yang, Z., Ding, W., Zhang, Y, et al. (2010). Catalytic Partial Oxidation of Coke Oven Gas to Syngas in an Oxygen Permeation Membrane Reactor Combined with NiO/MgO Catalyst, Int. 

Schematics of an oxygen membrane reactor for catalytic POx of methane. A blown up section on the left-hand side shows the details of the ceramic membrane wall explaining the mechanism of oxygen permeation across the membrane. /- is the chemical potential of oxygen and ai and

Biichi, F. N., Wakizoe, M. and Srinivasan, S. 1996. Microelectrode investigation of oxygen permeation in perfluorinated proton exchange membranes with different equivalent weights. Journal of the Electrochemical Society 143 927-932. 

Zhang, L., Ma, C. and Mukerjee, S. 2003. Oxygen permeation studies on alternative proton exchange membranes designed for elevated temperature operation. Electrochimica Acta 48 1845-1859. 

Xu, S.J. and Thomson, W.J. (1999) Oxygen permeation rates through ion-conducting perovskite membranes. Chemical Engineering Science, 54, 3839-3850. 

The permeation technique as discussed in the context of permeation membranes in Section II.2, can also be used to determine diffusion coefficients and minority conductivities (in fact steady-state oxygen flux that is given by (see Eq. (34))... 

Lin, Y. S., Wang, W., and Han, J. (1994). Oxygen permeation through thin mixed-conducting solid oxide membranes, AIChE J. 40(5), 786. 

FIGURE 10.3 (a) Hydrogen and (b) oxygen permeation through dense oxide ceramic membranes. 

In this figure the oxygen permeation is plotted as a function of the relative pressure of cyclohexane. The curve, which was obtained from the membrane before the CVI-experiment, shows a clear transition point. This is indicative of a mesoporous material, in this case with a calculated Kelvin radius of 2.5 nm. For the membrane after CVI no such curve could be obtained and no clear transition point could be observed. This behaviour is representative for microporous materials. 

Metals such as Zr and Nb have also been proposed for H2 permselective dense membranes [1]. Dense silver membranes have been used for selective oxygen permeation [18],... 

Therefore, assnming an effective area size as S and a membrane thickness as L, respectively, the total jonle heat value caused by oxygen permeation can be derive as ... 

Even though further detailed energy analysis and measurements of actual temperature distribution in the membrane are required, the joule heat caused by oxygen permeation (8.4 W) appears to be originating from AG of reforming reactions and returns to the system to be used as a part of heat required for POX and SMR reactions [11]. 

---