Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Sang-Koo Kwon is active.

Publication


Featured researches published by Sang-Koo Kwon.


High Temperature Materials and Processes | 2005

Suppression of the conversion process of Fe(OH)(3) to beta-FeOOH and alpha-Fe2O3 by silicate ions

Sang-Koo Kwon; Ken'ichi Kimijima; Kiyoshi Kanie; Atsushi Muramatsu; Shigeru Suzuki; Eiichiro Matsubara

The influence of the addition of silicate ions on the conversion processes of condensed ferric hydroxide Fe(OH)j gel to ferric oxyhydroxides and iron oxides was investigated under constant initial [Fe]/[OH~] ratio or constant initial pH. Fe(OH)3 gel, prepared from FeCl3 and NaOH solution, was aged at 333 Κ or 373 Κ in the presence and absence of silicate ions. The aged suspensions of each stage with colloidal state were separated into solid particles and supernatant solutions by centrifugation. Powder X-ray diffraction (XRD), transmission electron microscopy (TEM) and infrared spectroscopy (IR) were used to characterize the resultant solid particles. pH measurement and inductively coupled plasma (ICP) analyses were also carried out to obtain pH value and concentration of ferric and silicate ions in the supernatant solutions. XRD patterns and TEM micrographs revealed that silicate ions suppressed the conversion of the Fe(OH)3 gel to ß-FeOOH and a-Fe203 particles in both cases. Also, a decrease in nucleation number of a-FeiO^ particles resulted in larger particle size of final stage and the morphology became ellipsoidal with increase of aspect ratio by the specific adsorption of silicate ions. Analysis of pH curve indicated that silicate ions inhibited both dissolution from Fe(OH)3 gel to ßFeOOH and crystallization of ß-FeOOH particles. ICP and IR analyses showed that silicate ions had remarkably strong affinity with ferric ion by forming adsorbed silicon species on solid particles and this was a decisive factor for the suppression of the conversion process.


Corrosion Science | 2007

Influence of silicon on local structure and morphology of γ-FeOOH and α-FeOOH particles

Sang-Koo Kwon; Kozo Shinoda; Shigeru Suzuki; Yoshio Waseda


Corrosion Science | 2007

Influence of silicate ions on the formation of goethite from green rust in aqueous solution

Sang-Koo Kwon; Ken’ichi Kimijima; Kiyoshi Kanie; Shigeru Suzuki; Atsushi Muramatsu; Masatoshi Saito; Kozo Shinoda; Yoshio Waseda


Isij International | 2005

Inhibition of conversion process from Fe(OH)3 to β-FeOOH and α-Fe2O3 by the addition of silicate ions

Sang-Koo Kwon; Ken'ichi Kimijima; Kiyoshi Kanie; Atsushi Muramatsu; Shigeru Suzuki; Eiichiro Matsubara; Yoshio Waseda


Materials Transactions | 2005

Effect of Silicate Ions on Conversion of Ferric Hydroxide to β-FeOOH and α-Fe2O3

Sang-Koo Kwon; Ken’ichi Kimijima; Kiyoshi Kanie; Atsushi Muramatsu; Shigeru Suzuki; Eiichiro Matsubara; Yoshio Waseda


Corrosion Science | 2005

Influence of foreign ions on the atomic scale structure of ferric oxyhydroxides

Sang-Koo Kwon; Shigeru Suzuki; Masatoshi Saito; Yoshio Waseda


Corrosion Science | 2005

Atomic-scale structure of β-FeOOH containing chromium by anomalous X-ray scattering coupled with reverse Monte Carlo simulation

Sang-Koo Kwon; Shigeru Suzuki; Masatoshi Saito; Takayuki Kamimura; Hideaki Miyuki; Yoshio Waseda


Isij International | 2007

Analysis of Iron Oxyhydroxides and Oxides Converted from Green Rust in Aqueous Solution

Katsuya Inoue; Sang-Koo Kwon; Ken'ichi Kimijima; Kiyoshi Kanie; Atsushi Muramatsu; Kozo Shinoda; Shigeru Suzuki; Yoshio Waseda


Corrosion Science | 2006

Atomic-scale structure and morphology of ferric oxyhydroxides formed by corrosion of iron in various aqueous media

Sang-Koo Kwon; Shigeru Suzuki; Masatoshi Saito; Yoshio Waseda


Materials Transactions | 2006

Atomic-Scale Structure and Morphology of Ferric Oxyhydroxides Formed by Corrosion of an Iron–Silicon Alloy

Katsuya Inoue; Sang-Koo Kwon; Shigeru Suzuki; Masatoshi Saito; Yoshio Waseda

Collaboration


Dive into the Sang-Koo Kwon's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge