The oxygen content of YBa2Cu3O7, (LaSr)(8)Cu8O20, La4BaCu5O13, La2Sr6C
u8O16 and La2CuO4 is reduced by hydrogen in different steps to metasta
ble reaction products at 160-450 degrees C and the stable decompositio
n product of metallic Cu and different oxides above 420-730 degrees C.
Similar reactions were also observed for CH3OH, which reacts catalyti
cally above approximate to 200 degrees C. The behaviour of CH4 is simi
lar to an inert gas below approximate to 450 degrees C.