Paper ID : 1260-MST2015-FULL
Arash Helmi *1, Fausto Gallucci2, Martin van Sint Annaland1
1Chemical Process Intensification, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513, 5612 AZ Eindhoven, The Netherlands
2Eindhoven University of Technology
Higher process efficiency and smaller reactor volumes can be achieved via integration of separation and reaction in one single unit. An example of integrated reactors is the membrane assisted reactor for hydrogen production via water gas shift (WGS). Removal of hydrogen from the reaction zone can shift the thermodynamic equilibrium toward full conversion of CO and at the same time providing an ultrapure stream of hydrogen suitable for proton exchange membrane fuel cell (PEMFC) applications.
When ultra-thin membranes are used in a packed bed membrane reactor, the external mass transfer limitations in the catalyst bed result in a much lower concentration of hydrogen at the surface of membrane and consequently decrease the membrane performance in terms of total hydrogen flux. Since the high cost of palladium is the main barrier for commercialization of membrane reactor based technologies, it is of paramount importance to maximize the efficiency of membranes inside the membrane reactor. Fluidized bed reactors, with their excellent mass and heat transfer properties, are able to enhance mass transfer rates from the bulk to the surface of the membrane and thus decrease the required membrane area and ultimately the costs associated with the amount of Pd. The main goal of this research is the proof-of-concept and long term stability test of ultra-thin palladium based membranes integrated in a fluidized bed membrane reactor at various operating conditions.
After successful integration of catalyst and membranes inside the membrane reactor setup the long term performance of the membrane reactor was checked for water gas shift reaction. The performance of the membrane reactor in terms of CO conversion, H2 recovery, membrane permeability and hydrogen purity was monitored for long time. Effect of process parameters as temperature, pressure, steam to carbon ratio and inlet gas velocity was assessed and reproducibility assured.
Fluidized bed, membrane, hydrogen, PEMFC
Status : Paper Accepted (Oral Presentation)