Dense hydrogen perm-selective membranes

The flux term depends on the membrane used. For hydrogen production and purification, dense hydrogen perm-selective membranes are often used, which often exhibit (virtually) infinite selectivity toward hydrogen (in the case of Pd-based dense membranes). In this particular case, the flux term reduces to the flux of hydrogen though the membrane, and it is equal to zero for all the other components. To compute... 

Among all types of membranes, the inorganic dense membranes have attracted the interest of many researchers due to their capacity to separate completely a product from gaseous mixtures [19]. In particular, the dense palladium membranes are used because of their complete hydrogen perm-selectivity. In the last years, the increasing interest towards this type of membranes is, also, due to hydrogen application as energy carrier. 

The majority of the dense Pd or its alloy membrane is used in hydrogen production because of its infinite perm-selectivity. It has been demonstrated that the Fl2 recovery and purity levels in Pd-MRs can reach as high as 99% and 99.9999%, respectively without the use of a sweep gas. Table 4.4 summarizes the reactions for H2 production in the Pd-MRs. 

---