Journal of the Ceramic Society of Japan
Online ISSN : 1348-6535
Print ISSN : 1882-0743
ISSN-L : 1348-6535
Full papers
The effects of the addition of calcium phosphate on catalytic activities for ammonia decomposition on CoMo-based catalysts
Takuya EHIROKazuaki KATAGIRIShimpei YAMAGUCHITakashi NISHIMURAMakoto SAITOYayoi YOSHIOKA
Author information
JOURNAL OPEN ACCESS
Supplementary material

2019 Volume 127 Issue 11 Pages 802-809

Details
Abstract

In this study, wet impregnation method and sol–gel technique were used to prepare CoMo-based catalysts supported on two types of porous silicas containing calcium phosphate. The prepared catalysts were characterized using various techniques, such as N2 adsorption–desorption measurement, scanning electron microscope, X-ray diffraction (XRD), fourier transform infrared spectroscopy (FT-IR), differential thermal analysis, and X-ray photoelectron spectroscopy. The catalysts were tested for ammonia decomposition to produce COx-free hydrogen. The results of the XRD and FT-IR measurements elucidated that the crystal structure of calcium phosphate on the silica supports was attributed to calcium hydroxyapatite (HAp). The addition of calcium phosphate changed the porous structures of the catalysts, and decreased their BET surface areas and total pore volumes. Furthermore, the catalytic activity of the CoMo-based catalysts was influenced by the amount of calcium phosphate added. It was observed that the ammonia conversion at 873 K was increased by a maximum of 12.6% when 0.5 wt% of calcium phosphate was added to the catalyst, while a further addition of calcium phosphate beyond 1.0 wt% inhibited the ammonia conversion. From this study, it was concluded that HAp could work as a promoter for ammonia decomposition.

Content from these authors
© 2019 The Ceramic Society of Japan

この記事はクリエイティブ・コモンズ [表示 4.0 国際]ライセンスの下に提供されています。
https://creativecommons.org/licenses/by/4.0/deed.ja
Previous article Next article
feedback
Top