Extraction of hydrogen from water vapor by hydrogen pump using ceramic proton conductor

Kawamura, Yoshinori; Konishi, Satoshi; Nishi, Masataka

Aiming at realization of the efficient blanket tritium recovery system of a fusion reactor, research and development of the hydrogen pump using the proton conductor are furthered. One of the advantages of the system using the hydrogen pump is concurrent processing of hydrogen isotopes and water vapor by one component. In this work, experimental research on the hydrogen extraction characteristic in a water molecule was performed with the hydrogen pump using SrCeYbO. In hydrogen extraction from a water molecule, application of the threshold, voltage corresponding to the decomposition energy of water, is necessary. The observed threshold was about 500-600mV at 873K and decreased with the increase in water vapor pressure. About pumping of H-HO mixture gas, the permeation of H anteceded water decomposition, and the threshold of water decomposition increased with the increase in hydrogen partial pressure. In order to process concurrently, application of fairly higher voltage is expected to be necessary.