Group Leader, Membrane Separation Processes Group,
Research Institute for Chemical Process Technology,National Institute of Advanced Industrial Science and Technology (AIST), Japan
(https://www.aist.go.jp/index_en.html)
(email: h-negishi@aist.go.jp)
Address: AIST Central-5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
I am investigating the preparation of silicalite membranes by hydrothermal synthesis with electrophoretic deposition as a seeding technique. Silicalite is a kind of zeolite. About 2 μm of silicalite powder were deposit on the porous stainless steel tube. After hydrothermal synthesis, the obtained silicalite membrane show high separation performance of alcohol from alcohol/water. These membranes are applied to refinement of bio-alcohol, such as bio-ethanol and bio-butanol.
An energy efficient adsorption system using low-temperature waste heat attracts attention from the growing interest in the global environment. In order to realize energy-saving desiccant air conditioning technology, I am also studying mesoporous silica (MPS) thick coating on aluminum substrate using ordered MPS powder. MPS powder about 10 μm in diameter was deposited in acetone to obtain a uniform coating about 250 μm thick. The obtained MPS thick film showed rapid water vapor adsorption / desorption characteristics.
In addition, I am studying the fundamental dc-EPD mechanism of oxide powder in organic suspension. For example, it is extremely power saving EPD and the effect of electroosmotic flow in a porous substrate.
Selected publications
•H. Negishi, K. Yamaji, T. Imura, D. Kitamoto, T. Ikegami and H. Yanagishita, Electrophoretic deposition mechanism of YSZ/n-propanol suspension, J. Electrochem. Soc., 152(2), J16-J22 (2005)
・H. Negishi, M. Okamoto, T. Imura, D. Kitamoto, T. Ikegami, Y. Idemoto, N. Koura, T. Sano and H. Yanagishita, Preparation of Tubular Silicalite Membrane by Hydrothermal Synthesis with Electrophoretic Deposition as a Seeding Technique, J. Am. Ceram. Soc., 89 (1), 124-130 (2006)
・H. Negishi, A. Miyamoto, A. Endo, Preparation of thick mesoporous silica coating by electrophoretic deposition and its water vapor adsorption-desorption properties, Microporous and Mesoporous Materials, 180, 250-256 (2013)
・H. Negishi, Uniform and ultra low-power electrophoretic deposition of silica powder using a nonflammable organic solvent, J. Euro. Ceram. Soc., 36(2), 285-290 (2016)
・K. Ueno, H. Negishi, M. Miyamoto, S. Uemiya, Y. Oumi, Effect of deposition seed crystal amount on the alpha-Al2O3 support and separation performance of silicalite-1 membranes for acetic acid/water mixtures, Separation and Purification Technology, 174, 57-65 (2017)
・H. Negishi, K. Ueno and Y. Oumi, Effect of Electroosmotic Flow on the Electrophoretic Deposition of Zeolite Powder on a Porous Alumina Support, ECS Transactions, The Electrochemical Society, 82 (1) 13-18 (2018)
