樊君a; 胡晓云b; 大矢晴彦c; 上田义人c; 山胁正也c; 相原雅彦c; 竹内隆c; 根岸洋一c
FAN Juna; HU Xiaoyunb; OHYA Haruhikoc; EDA Yoshihitoc; YAMAWAKI Masayac; AIHARA Masahikoc;
TAKEUCHI Takashic; NEGISHI Youichic
摘要: Palladium membranes were prepared on an α-alumina support by metal-organic compound
chemicalvapor deposition (MOCVD) method from palladium(Ⅱ) acetate precursor. Permeation
properties of hydrogen andhelium gas were studied as a function of the number of times of
deposition of palladium on the peeling off phenomenonof palladium, which is common in
electroless plated membrane, was observed. Silica was introduced into the pores toprevent
the palladium grain from peeling off. The palladium-silica conjugated membrane does not
show the peelingoff phenomenon and can withstand the high temperature up to 800℃ which is
the upper limit of our apparatus.The separation factor for hydrogen gas over carbon dioxide
gas was improved with the increase of number of timesof silica coating by sacrificing the
H2 permeation and finally increased to four times. The improvement on theseparation of
hydrogen gas over carbon dioxide for palladium-silica conjugated membrane was evaluated and
amodel of permeation pattern (palladium and silica) was proposed. This model suggests that
the separation factorfor hydrogen over carbon dioxide could be improved by introducing
silica layer because the silica layer fills the poresand reduces the gas permeation without
sacrificing the hydrogen permeation through the palladium region. Theseresults indicate
that the introduction of silica into the palladium grain is a promising means to improve
the hydrogenseparation performance of palladium based composite membranes.