触媒被覆層をもつメタン部分酸化触媒粒子の流動層合成

抄録

High-temperature fluidized-bed coating on alumina balls of 300-μm was carried out to produce particles covered with Ni-calcium hydroxyapatite (Ni-HAp) catalyst layer for partial oxidation of methane. The attrition durability of the catalyst-coated particles was investigated by a cold-model fluidization method. The catalytic partial oxidation of methane (POM) was demonstrated at 1073K in a fluidized bed reactor, where the catalyst-coated particles were fluidized by the reactant gas mixture. The effect of Ni loading (2.5wt.％ and 12.4wt.％ of the catalyst layer), superficial gas velocity on the CH₄ conversion and H₂ yield was investigated. The results clarified that the coating efficiency was improved by decreasing the superficial gas velocity. The catalyst particles produced in the present work had fair attrition durability, showing 5wt％ loss of catalyst layer after 48h fluidization at 0.60m/s. The CH₄ conversion increased with decreasing superficial gas velocity, reaching more than 95％ at 0.18m/s irrespective of Ni loading of Ni-HAp catalyst used in the present work. An optimum superficial gas velocity was found, at which the CO selectivity and the H₂ selectivity were both high.