Faculty Profiles - NAGAOKA Katsutoshi

In recent years, with the innovation of shale gas excavation technology, dry reforming of methane has been attracting attentions. Co-Mg-O solid solution catalyst are known to resist coking. However, most of Co in this catalyst remained unreduced even by H2 treatment at high temperature and number of active site is very small. Resultantly, this catalyst is easily deactivated due to oxidation of Co. In contrast, we revealed that Al doping on Co-Mg-O solid solution catalyst significantly improves reduction degree of Co and enhances durability of the catalyst. In this work, we investigated state of Al by using 27Al NMR and influence of Al loads on catalytic property.

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Development of Efficient Cold-start Process for Oxidative Reforming of n-Butane for Fuel Cell Applications

Nagaoka Katsutoshi, Sato Katsutoshi

Journal of the Japan Petroleum Institute Vol. 58 ( 5 ) page： 274 - 284 2015

Language：Japanese Publisher：The Japan Petroleum Institute

Efficient cold-start process of hydrogen production by oxidative reforming (OR) of hydrocarbon was developed using Rh catalyst supported on carriers with redox properties. In this process, the heat generated by re-oxidation of reduced catalyst rapidly heats the catalyst from ambient temperature to the catalytic auto-ignition temperature of the OR. OR was triggered at ambient temperature over Rh/CeO2 after reduction at 873 K, but not over Rh catalysts supported on Pr6O11 and Tb4O7, oxides of rare earth elements with redox characters like cerium. Over the latter catalysts, reduction of the carrier occurred at lower temperatures than over CeO2, but the reduced oxides were not re-oxidized at ambient temperature. Our results emphasized that re-oxidation as well as reduction of the catalyst are the key characteristics of the carrier for triggering OR at ambient temperature. With the use of Rh/Ce0.5Zr0.5O2 with excellent redox properties at low temperature, triggering OR of hydrocarbons at ambient temperature was achieved even under non-adiabatic conditions, where heat losses occur, over the catalyst after reduction at 373 K and after in-situ reduction by hydrogen formed during the OR. This new catalytic process is expected to be useful for the development of self-sufficient reforming processes for a new generation of fuel cells.

DOI： 10.1627/jpi.58.274

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Construction of cold-start process for H2 production from hydrocarbons or ammonia

Nagaoka Katsutoshi

Proceeding of Annual/Fall Meetings of the Japan Petroleum Institute Vol. 2015 ( 0 ) 2015

Language：Japanese Publisher：The Japan Petroleum Institute

We have constructed cold-start process for oxidative reforming of hydrocarbons or oxidative decomposition of ammonia without external energy input. For example, n-butane and O2 are just supplied to reduced Rh/CeO2 in the reactor at room temperature, and immediately after that, catalyst bed temperature rises to 850&nbsp; &deg;C and H2 and CO are produced. In this process, the heat produced by oxidation of CeO2-x to CeO2 increases catalyst bed temperature from room temperature to the catalytic auto-ignition temperature of the n-butane oxidative reforming. I will report cold-start mechanism, performance of developed catalysts, and strategy for designing effective catalysts.

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ハイドロタルサイトを前駆体とした担持Ni触媒によるアンモニア分解反応(第2報)酸化物添加効果の検討

安部成彦, 川越貴史, 佐藤勝俊, 永岡勝俊

石油・石油化学討論会講演要旨 Vol. 44th page： 335 2014.10