Faculty Profiles - ICHINO, Ryoichi

Papers - ICHINO, Ryoichi

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Synthesis of MOR Zeolite/Magnetite Composite via Seed Assisted Method Reviewed International coauthorship International journal

Hagio Takeshi, Nijpanich Supinya, Kunishi Hiroto, Yamaoka Keiichi, Phouthavong Vanpaseuth, Kamimoto Yuki, Ichino Ryoichi, Iwai Kazuhiko

JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY Vol. 19 ( 10 ) page： 6841 - 6848 2019.10

Electrodeposition of rare-earth elements from neodymium magnets using molten salt electrolysis Reviewed International journal

Kamimoto Y., Itoh T., Yoshimura G., Kuroda K., Hagio T., Ichino R.

JOURNAL OF MATERIAL CYCLES AND WASTE MANAGEMENT Vol. 20 ( 4 ) page： 1918 - 1922 2018.10

Electrodeposition of Copper / Carbonous Nanomaterial Composite Coatings for Heat-Dissipation Materials Reviewed International journal

Yasuki Goto, Yota Kamebuchi, Takeshi Hagio, Yuki Kamimoto, Ryoichi Ichino, Takeshi Bessho

Coatings Vol. 8 ( 1 ) page： 1-10 2018.1

Effect of the Addition of Molybdenum on the Structure and Corrosion Resistance of Zinc-Iron Plating Reviewed International journal

Kosugi Daichi, Hagio Takeshi, Kamimoto Yuki, Ichino Ryoichi

COATINGS Vol. 7 ( 12 ) 2017.12

Recovery of rare-earth elements from neodymium magnets using molten salt electrolysis Reviewed International journal

Kamimoto Y., Itoh T., Kuroda K., Ichino R.

JOURNAL OF MATERIAL CYCLES AND WASTE MANAGEMENT Vol. 19 ( 3 ) page： 1017 - 1021 2017.7

Phosphorus removal and magnetic separation using magnetic schwertmannite Reviewed International coauthorship International journal

Kamimoto Yuki, Yamauchi Kazushige, Hagio Takeshi, Ichino Ryoichi, Min Kyung Sok, Kwon Koo Ho, Kim Ye Jin, Jung Yong Jun

DESALINATION AND WATER TREATMENT Vol. 63 page： 463 - 468 2017

Removal properties of phosphate with Ettringite Reviewed International coauthorship International journal

Kamimoto Yuki, Onda Keita, Ichino Ryoichi, Min Kyung-Sok, Kwon Koo-Ho, Jung Yong-Jun

DESALINATION AND WATER TREATMENT Vol. 63 page： 478 - 482 2017

Ti<inf>3</inf>AlC<inf>2</inf> MAX Phase: A surprising candidate material for highly selective and efficient gold recovery from strong acid solutions Reviewed International coauthorship International journal

Thaveemas P., Phouthavong V., Hagio T., Dechtrirat D., Chuenchom L., Nijpanich S., Chanlek N., Park J.H., Ichino R.

Separation and Purification Technology Vol. 343 2024.9

Language：English Publishing type：Research paper (scientific journal) Publisher：Separation and Purification Technology

Given the scarcity of natural gold sources and associated mining challenges, the recovery of gold from secondary sources, such as electronic equipment waste (e-waste), becomes imperative. E-waste is typically treated with aqua regia to obtain highly acidic gold-containing solutions, which are subsequently processed by various methods to recover gold. Gold recovery materials offer numerous benefits but often exhibit insufficient selectivity, efficiency, and cost-effectiveness. To address this problem, we herein used a nonmodified pristine Ti-Al-C MAX phase (Ti3AlC2) to realize the one-pot room-temperature recovery of gold from highly acidic solutions (pH < 1) in the form of easily collectable bulky ball-shaped Au0 aggregates. High gold selectivity (Kd = 2.03 × 106 mL/g) and extraction efficiency (∼99 %) were observed even in the presence of interfering metal ions (Pd2+, Pt4+, Co2+, Ni2+, Cu2+, Zn2+), and the maximum gold extraction capacity (>6000 mg/g) surpassed that of previously reported gold recovery materials. The recovered gold was highly pure (>90 mass%) and contained minimal amounts of the original MAX phase, which obviated the need for intensive postpurification. The results of instrumental analyses suggested that gold recovery relied on electron transfer, similar to cementation, and primarily involved the reduction of solution-phase Au3+ to Au0 via electron transfer from the Ti and Al of Ti3AlC2. Thus, our work demonstrates the significant potential of pristine Ti3AlC2 for the energy-efficient recovery of gold from highly acidic solutions and paves the way for the efficient valorization of e-waste.

DOI： 10.1016/j.seppur.2024.127113

Scopus

Removal of heavy metals by BEA zeolite/Fe<inf>3</inf>O<inf>4</inf> composite prepared via dry-gel conversion method using agrowaste-derived raw material Reviewed International coauthorship

Phouthavong V., Hagio T., Park J.H., Nijpanich S., Duangkhai K., Rujiravanit R., Thaveemas P., Chounlamany V., Kong L., Li L., Ichino R.

Solid State Sciences Vol. 149 2024.3

Authorship：Last author Language：English Publisher：Solid State Sciences

Using agrochemicals are considered as an anthropogenic source of heavy metal contamination in water, and ecofriendly remediation tools for removal is desired. Here, we demonstrate material circulation by converting SiO2 extracted from agrowaste: rice husk ash, into an easily collectable adsorbent: BEA zeolite/Fe3O4 composite, through dry-gel conversion technique. In addition, the synthesized BEA zeolite/Fe3O4 composite was tested for removal of heavy metals for the first time. Instrumental analyses confirmed that incorporated Fe3O4 particles inside BEA zeolites showed no severe effects on its morphologies. Pseudo-second order kinetic and Langmuir isotherm models were found best described the adsorption of three typical toxic heavy metals: Pb(II), Cu(II), Zn(II). Moderate adsorption capacities of 0.675, 0.310, and 0.308 mmol/g for Pb(II), Cu(II), and Zn(II), respectively, following the selectivity order: Pb(II) > Cu(II) ≈ Zn(II) were obtained. The composite adsorbent exhibits magnetic collectability, reusability and stability, indicating its practicality for removal of heavy metals from water.

DOI： 10.1016/j.solidstatesciences.2024.107473

Scopus

Super hardening of Fe–W alloy plating by phase transformation of amorphous to metal carbides-dispersed nanocrystalline alloys and application as promising alternative for hard chromium plating Reviewed

Park J.H., Kim J.I., Shinohara Y., Hagio T., Umehara N., Ichino R.

Surface and Coatings Technology Vol. 477 2024.2

Authorship：Last author Language：English Publisher：Surface and Coatings Technology

Despite the superior hardness, wear resistance, and corrosion resistance of hard chromium (Cr) plating using toxic hexavalent chromium (Cr6+), the gradual restriction on the use of Cr6+ in industrial fields necessitates the development of an alternative, harmless plating material with excellent performance. Here, we report the fabrication of super-hard plating by the simple annealing of electrodeposited Fe–W–C plating as a promising alternative for hard Cr plating. Amorphous-structured Fe–W–C plating, including co-deposited citric acid-derived carbon, forms uniformly dispersed ternary metal carbides inside the plating during annealing, which changes the plating structure from amorphous to nano-carbide-dispersed alloys. The phase-transformed, nanocrystalline Fe–W–C alloy annealed at 700 °C exhibited a maximum hardness of 20.5 GPa, which surpassed the hardness of hard Cr plating (12.5 GPa). The ball-on-disc tribo-test and corrosion test results further demonstrated the superior wear and anti-corrosion properties of the carbide-dispersed Fe–W–C alloy plating compared with hard Cr plating. This study develops the applicability of this super-hard plating as a new hard coating material that overcomes the limitations of conventional metal plating without using any toxic chemical.

DOI： 10.1016/j.surfcoat.2024.130388

Scopus

Potential of C-plane Aligned Hexagonal Tungsten Oxide Film as a Molecular Sieve-type Separation Membrane Reviewed International coauthorship International journal

Hagio Takeshi, Kunishi Hiroto, Wada Shintaro, Terao Toshihiro, Kinoshita Sora, Phouthavong Vanpaseuth, Nijpanich Supinya, Park Jae-Hyeok, Ichino Ryoichi

Vol. 41 ( 1 ) page： 9 - 19 2024.1

Authorship：Last author Language：English Publishing type：Research paper (scientific journal) Publisher：Japan Association of Zeolite

Separation membranes are attracting increasing attention because they can contribute to realizing a carbon neutral and sustainable society through energy reduction of energy-consuming separation processes and through recycling of resources. Among numerous research elements on this topic, research on membrane materials is one topic of importance because it determines their separation characteristics. A group of inorganic crystals with molecular-sized micropores (microporous inorganic crystals), also called molecular sieves, are promising separation membrane material candidates. Among them, the authors have proposed hexagonal tungsten oxide as a potential molecular sieve-type membrane material. Because this material possesses uniaxial pores parallel to its crystallographic c-axis, c-plane oriented hexagonal tungsten oxide membrane is expected to function as a molecular sieve type-separation membrane; however, its application as a separation membrane material has not been considered. Here, we introduce our recent attempts on challenging to synthesize dense c-plane oriented hexagonal tungsten oxide film, and the experimental results seeking its possibility to apply as liquid/liquid and/or gas/gas separation membranes. The obtained membrane was confirmed to selectively separate water from a water/acetic acid mixture. Furthermore, results on the permeability of various liquids and gas molecules implied that the membrane functions as a molecular sieve-type separation membrane for small molecules through utilization of its micropores. This discovery is expected to contribute to expanding options for membrane materials.

DOI： 10.20731/zeoraito.41.1.9

CiNii Research

Facile Synthesis of Spherical Porous Tricobalt Tetroxide and Metal Cobalt for High Quality Cobalt Production and Recycling Reviewed

Matsunaga Shohei, Suzuki Takahiro, Hagio Takeshi, Park Jae-Hyeok, Kamimoto Yuki, Ichino Ryoichi, Takeshita Kyohei, Sato Fumiatsu, Sasaya Kazuo, Iguchi Takahisa, Tsunekawa Minoru

MATERIALS TRANSACTIONS Vol. 64 ( 12 ) page： 2739 - 2747 2023.12

Language：English Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Metals and Materials

<p>Liquid-phase synthesis is suitable for controlling the morphological and structural properties of functional inorganic materials and such control is important because they strongly affect the functionality of the product. Cobalt-based materials is one group of materials that requires control of powder morphology and structure. Cobalt is an important metal element used in various industrial fields such as secondary batteries, superalloys, permanent magnets, hard metals, and catalysts. The ever-growing demand of cobalt highlights that there is an urgent necessity to develop high quality material synthesis methods and to secure cobalt resources for countries that rely on import like Japan. Especially, technologies to recycle cobalt in a form reusable for secondary batteries and catalysts are desired because further increase in demand is anticipated. Meanwhile, spherical porous tricobalt tetroxide secondary particles obtained by calcination of spherical cobalt carbonate precursors have been reported to be promising materials for battery applications. Moreover, porous metal cobalt obtained by hydrogen reduction of tricobalt tetroxide is known to be effective for catalyst applications. However, conventional methods to synthesize spherical cobalt carbonate requires addition of additives in the reaction mixtures or otherwise requires hydrothermal treatment in pressure vessels. These are unfavorable to develop a practical and sustainable process for cobalt-based material production and recycling. In this study, a facile room temperature synthesis method to prepare spherical cobalt carbonate precursors from solutions of cobalt chloride and ammonium hydrogen carbonate that does not require any additives or hydrothermal treatment is developed by optimizing the carbonate solution concentration, carbonate/cobalt salt molar ratio, and stirring time during reaction. Furthermore, we succeeded in obtaining porous tricobalt tetroxide and porous metal cobalt that carry on the exterior spherical morphology of the original cobalt carbonate precursor by calcination and hydrogen reduction. The developed process shall contribute to realize high quality cobalt-based material production and recycling.</p>

DOI： 10.2320/matertrans.m-m2023809

Scopus

CiNii Research

AC Electromagnetic Field Controls the Biofilms on the Glass Surface by Escherichia coli & Staphylococcus epidermidis Inhibition Effect Reviewed

Aoyama N., Kanematsu H., Barry D.M., Miura H., Ogawa A., Kogo T., Kawai R., Hagio T., Hirai N., Kato T., Yoshitake M., Ichino R.

Materials Vol. 16 ( 21 ) 2023.11

Authorship：Last author Language：English Publishing type：Research paper (scientific journal) Publisher：Materials

Biofilms, mainly comprised of bacteria, form on materials’ surfaces due to bacterial activity. They are generally composed of water, extracellular polymeric substances (polysaccharides, proteins, nucleic acids, and lipids), and bacteria. Some bacteria that form biofilms cause periodontal disease, corrosion of the metal materials that make up drains, and slippage. Inside of a biofilm is an environment conducive to the growth and propagation of bacteria. Problems with biofilms include the inability of disinfectants and antibiotics to act on them. Therefore, we have investigated the potential application of alternating electromagnetic fields for biofilm control. We obtained exciting results using various materials’ specimens and frequency conditions. Through these studies, we gradually understood that the combination of the type of bacteria, the kind of material, and the application of an electromagnetic field with various low frequencies (4 kHz–12 kHz) changes the circumstances of the onset of the biofilm suppression effect. In this study, relatively high frequencies (20 and 30 kHz) were applied to biofilms caused by Escherichia coli (E. coli) and Staphylococcus epidermidis (S. epidermidis), and quantitative evaluation was performed using staining methods. The sample surfaces were analyzed by Raman spectroscopy using a Laser Raman spectrometer to confirm the presence of biofilms on the surface.

DOI： 10.3390/ma16217051

Scopus

PubMed

Gas permeation properties of c-plane aligned hexagonal tungsten oxide membranes formed by multi-stage synthesis Reviewed International coauthorship International journal

Wada S., Hagio T., Kunishi H., Park J.H., Phouthavong V., Yamada Y., Terao T., Li X., Nijpanich S., Ichino R.

Journal of the Korean Ceramic Society Vol. 60 ( 6 ) page： 967 - 978 2023.11

Authorship：Last author Language：English Publishing type：Research paper (scientific journal) Publisher：Journal of the Korean Ceramic Society

Crystalline microporous membranes are promising tools for gas separation because their molecular dimension pores allow us to accurately sieve molecules by size. Recently, microporous hexagonal WO3 was reported as a new potential membrane material and its membrane was found to enable separation of water from water/acetic acid mixtures. Pore size of hexagonal WO3 seemed to be also suitable for separation of small gasses; however, its gas permeation properties have not been reported. Additionally, densification of membranes by decreasing intercrystalline gaps are extremely important in gas separation. One effective method to densify polycrystalline membranes is to repeat membrane synthesis, namely multi-stage synthesis. Here, we attempt to prepare dense hexagonal WO3 membranes on porous tubular supports by multi-stage synthesis and examined their densification and gas permeation properties. Densification was confirmed by permeation of SF6 (gas molecule larger than pores of hexagonal WO3), and its potential for separating small gasses was considered from single gas permeation of He and He/SF6 permselectivity. The results indicated that the multi-stage synthesis is effective to densify the membranes and He/SF6 permselectivity reached 42.8 for three-stage synthesis under modified conditions, implying hexagonal WO3 is a potential membrane material for small gas separation.

DOI： 10.1007/s43207-023-00321-5

Scopus

Synthesis of Sulfur-Doped Magnetic Iron Oxides for Efficient Removal of Lead from Aqueous Solutions Reviewed International coauthorship

Xu J., Pan M., Zou C., Huang X., Hagio T., Ichino R., Kong L., Li L.

Water (Switzerland) Vol. 15 ( 20 ) 2023.10

Language：English Publishing type：Research paper (scientific journal) Publisher：Water (Switzerland)

Heavy metal pollution poses an environmental risk, and its efficient removal and facile separation from water remains a challenge. Magnetic iron oxide, an eco-friendly, relatively stable, and easy-separation material, has been regarded as one of the most applicable adsorbents for water treatment. However, the limited adsorption capacity has restricted its applications. Herein, sulfur-doped magnetic Fe3O4 (Sx–Fe3O4) adsorbent was fabricated using a calcination method for the efficient removal of Pb(II) from water. In contrast to undoped Fe3O4, the introduction of doped sulfur greatly enhanced the adsorption performance of S–Fe3O4 over four times, with a maximum capacity of 333.33 mg g−1, which was synthesized at 300 °C with a raw molar ratio of S–Fe of 5. Based on the structure and morphology analysis, it was demonstrated that sulfur was successfully doped into the Fe3O4 structures, which resulted in Fe3O4 with active sulfur sites accordingly contributing to the adsorption enhancement through the combination of strong soft–soft interactions between soft base sulfur and soft acid Pb(II) along with surface adsorption. Sx–Fe3O4 could maintain the adsorption performance in the presence of competing ions. Furthermore, although the sulfur doping process exhibited slight side effects on the magnetic property, magnetic Sx–Fe3O4 maintained the high separation potential. This study presented a promising strategy to enhance the adsorption performance of Fe3O4 through sulfur doping for Pb(II) removal from water.

DOI： 10.3390/w15203667

Scopus

Preparation and Characterization of TiO<inf>2</inf>-Coated Hollow Glass Beads for Functionalization of Deproteinized Natural Rubber Latex via UVA-Activated Photocatalytic Degradation Reviewed

Nijpanich S., Nimpaiboon A., Rojruthai P., Park J.H., Hagio T., Ichino R., Sakdapipanich J.

Polymers Vol. 15 ( 19 ) 2023.10

Language：English Publishing type：Research paper (scientific journal) Publisher：Polymers

The photochemical degradation of natural rubber (NR) is a prevalent method used to modify its inherent properties. Natural rubber, predominantly derived from the Hevea Brasiliensis tree, exhibits an exceptionally high molecular weight (MW), often reaching a million daltons (Da). This high MW restricts its solubility in various solvents and its reactivity with polar compounds, thereby constraining its versatile applications. In our previous work, we employed TiO2 in its powdered form as a photocatalyst for the functionalization of NR latex. However, the post-process separation and reuse of this powder present substantial challenges. In this present study, we aimed to functionalize deproteinized NR (DPNR) latex. We systematically reduced its MW via photochemical degradation under UVA irradiation facilitated by H2O2. To enhance the efficiency of the degradation process, we introduced TiO2-coated hollow glass beads (TiO2-HGBs) as photocatalysts. This approach offers the advantage of easy collection and repeated reuse. The modified DPNR showed a reduction in its number-average MW from 9.48 × 105 to 0.28 × 105 Da and incorporated functional groups, including hydroxyl, carbonyl, and epoxide. Remarkably, the TiO2-HGBs maintained their performance over seven cycles of reuse. Due to their superior efficacy, TiO2-HGBs stand out as promising photocatalysts for the advanced functionalization of NR across various practical applications.

DOI： 10.3390/polym15193885

Scopus

PubMed

Improvement in the corrosion resistance of electrodeposited Ni-W alloy by MWCNT co-deposition and prevention of metal-carbon interfacial corrosion by carbide formation Reviewed

Park J.H., Hagio T., Ichino R.

Journal of Alloys and Compounds Vol. 939 2023.4

Authorship：Last author Language：English Publishing type：Research paper (scientific journal) Publisher：Journal of Alloys and Compounds

Composite plating is an effective method which can enhance the properties of conventional metal plating by co-deposition of composite materials. In this study, multi-walled carbon nanotubes (MWCNTs) were used as a composite material to improve the corrosion resistance of Ni-W alloys, and the effect of the MWCNTs addition on the anti-corrosion properties was discussed. The corrosion current density of the Ni-W/MWCNTs composite decreased approximately 4 times from 16.6 to 4.6 μA·cm-2 in 3 wt% NaCl solution compared to the pristine Ni-W; this showed that the co-deposition of MWCNTs was effective for improvement in the corrosion resistance. However, the interfacial corrosion between the metal matrix and MWCNTs occurred in the high potential region and degraded the passivation properties of plating. This interfacial corrosion is caused by the high O content due to the hydroxyl groups on the acid-treated MWCNTs surface and the difference in W concentration between the interface of MWCNTs and the Ni-W matrix. Heat treatment in Ar atmosphere removes these hydroxyl groups and diffuses Ni and W into MWCNTs to form metal carbide (Ni6W6C), effectively alleviating interfacial corrosion. This study presents interfacial corrosion can be effectively mitigated by forming metal carbides at the interface of carbon materials in metal/carbon composites.

DOI： 10.1016/j.jallcom.2023.168788

Scopus

Dry-gel conversion synthesis of magnetic BEA-type zeolites for antibiotics adsorption Reviewed International coauthorship

Phouthavong V., Hagio T., Nijpanich S., Park J.H., Hiraiwa M., Srihirunthanon T., Chantanurak N., Rujiravanit R., Kamimoto Y., Li X., Kong L., Li L., Ichino R.

Journal of Sol-Gel Science and Technology Vol. 105 ( 2 ) page： 511 - 524 2023.2

Authorship：Last author Language：English Publishing type：Research paper (scientific journal) Publisher：Journal of Sol-Gel Science and Technology

The dry-gel conversion method (DGC) is a promising synthesis protocol for preparing magnetic zeolite composites as it yields homogeneous composite particles with more rapid crystallization, smaller reactor volume, and less waste production than the conventional hydrothermal method. This work investigates the optimal conditions for preparing magnetic BEA-type zeolites using the DGC method, including the gel/water ratio, crystallization temperature and time. Precursor dry-gel incorporating well-dispersed magnetite was subjected to crystallization under water vapor atmosphere with a gel/water ratio of 0.5–2, crystallization temperature of 140–200 °C for 1.5–12 h, followed by characterization using X-ray diffraction and scanning electron microscopy. The optimum conditions were found to be gel/water ratio of 1 and crystallization at 180 °C for 12 h. Magnetic properties of collected samples were evaluated using a vibrating-sample magnetometer after calcination at 400–500 °C for 12 h. Products calcined below 450 °C showed good magnetic properties. Adsorption of sulfadiazine using the BEA and magnetic BEA-type zeolites was evaluated in a 10–50 mg/l range. Results revealed favorable multilayer-type adsorption of sulfadiazine onto both non-magnetic and magnetic BEA-type zeolites (Freundlich model). These indicate that DGC method is suitable for preparing high-silica magnetic BEA-type zeolites with potential for antibiotic removal. Graphical Abstract: [Figure not available: see fulltext.].

DOI： 10.1007/s10971-022-06025-2

Scopus

Aluminum Electrodeposition on the Surface of Boron Carbide Ceramics by Use EMIC–AlCl<inf>3</inf> Ions Liquid Reviewed

Gou R., Park J.H., Yamashita S., Hagio T., Ichino R., Kita H.

Coatings Vol. 12 ( 10 ) 2022.10

Language：English Publisher：Coatings

Coating technology is decisively important for metallization of ceramic materials and ceramic metal sealing technology. Previous studies have shown that the network-like structure after penetration of molten aluminum can significantly improve the strength of joint components. However, the direct aluminum coating method is limited by the shape of the substrate. To obtain a dense aluminum film on the surface of B4C, in this study, aluminum was deposited by pulse electroplating in EMIC–AlCl3 ionic liquid. The deposited metals were observed and analyzed by SEM–EDS and XRD. A Vickers hardness tester was adopted as an auxiliary equipment to clarify the film quality. The results show that frequency and duty cycle have significant effects on crystal orientation. The content of oxides in the contact gap reduces the bonding strength of the deposited metal, which provides experimental basis for metal electrodeposition on B4C.

DOI： 10.3390/coatings12101535

Scopus

Facile synthesis of amine-functionalized three-dimensional graphene composites for CO2 capture Reviewed International coauthorship

Sun Hefei, Zhang Qinggang, Hagio Takeshi, Ryoichi Ichino, Kong Long, Li Liang

SURFACES AND INTERFACES Vol. 33 2022.10

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Papers - ICHINO, Ryoichi