Plasma and Fusion Research

Volume 19, 1205012 (2024)

Rapid Communications

New Silica Removal Technique by Vacuum Heating toward High-Performance Cryosorption Pumps Based on Biomass-Based Activated Carbon
Yuto YANAGIHARA1), Takanori MURASE1), Hiroyuki NOTO1), Kunihiro OGAWA1,2), Akihiro SHIMIZU1,2), Mitsutaka ISOBE1,2), Kazuki NAGAHARA1), Hiroyuki TANOUE1), Sho NAKAGAWA1), Yuki HAYASHI1,2), Ngat T.H. PHAM3), Tomohiro SHIOZAKI3), Toshiaki SOGABE3) and Mudtorlep NISOA4)
National Institute for Fusion Science, National Institutes of Natural Sciences, 322-6 Oroshi-cho, Toki 509-5292, Japan
The Graduate University for Advanced Studies, SOKENDAI, 322-6 Oroshi-cho, Toki 509-5292, Japan
ANAORI CARBON Co., Ltd., 6-20 Hatakeda-cho, Ibaraki 567-0028, Japan
Functional Materials & Nanotechnology CoE, Walailak University, Nakhon Si Thammarat, 80160, Thailand
(Received 15 December 2023 / Accepted 9 January 2024 / Published 27 February 2024)


We developed a new silica (SiO2) removal technique that can maximize biomass-based activated carbon adsorption performance. SiO2 removal is one of the key processes in making activated carbon suitable for cryosorption pumps in fusion machines. In this study, we employed an evaporation process to remove SiO2 by high-temperature vacuum heating. The charcoal made from rice straw was heated at 1800℃ for 1 h at approximately 10 Pa in a vacuum furnace. We found that SiO2 amount was significantly reduced from 15.8 wt% to 4.20 wt% due to vacuum heating. In addition, the result of surface element mapping analysis using energy-dispersive X-ray spectroscopy (EDX) indicated a considerable decrease in the oxygen content of SiO2. We demonstrated the great potential of activated carbon derived from rice straw as an adsorbent for high-performance cryosorption pumps.


cryosorption pump, activated carbon, silica, vacuum heating, unutilized biomass

DOI: 10.1585/pfr.19.1205012


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