抄録
In order to construct a high-performance microreactor used to conduct heterogeneous catalytic reactions, it is necessary to prepare a porous catalytic wall with high surface area on the microchannel. In this study, with the purpose of preparing of such wall, microchannels plated with copper-based components by electroless plating were prepared on the inner walls of aluminum tubes with micron-order diameter. The preparation procedure by electroless plating was as follows: activation of the inner walls of aluminum tubes by hydrogen chloride solution, displacement plating of zinc, intermediate plating of iron, and chemical reduction plating of copper. Each process solutions were flowed into aluminum tubes by a suction pump. The physicochemical properties and the steam reforming properties of methanol for the plated channel were then investigated. SEM photographs of the surface and section of the plated wall showed that the preparation used in this study produced catalytic components with a film thickness of about 100µm that were deposited porously on the inner surface of microchannels. An elemental analysis indicated that the plated wall consisted of copper and zinc, with the latter being detected in a wide area from the bulk to the surface of the wall. Microchannel-type copper-based catalyst oxidized by air were significantly higher in activity of methanol reforming than that reduced by hydrogen, indicating that the conversion was 100% and a hydrogen production rate was 0.07mol/h at 150°C with the channel length of 450mm. Even after the activity of the oxidized catalyst was declined, it restored its initial activity by reoxidation. The activity restoration by reoxidation could be repeated. These results show that the microchannel-type catalyst wall prepared in this study have high catalytic performance for reforming microreactor.
