Article
Environmental Sciences
Xu Ma, Jiaxi Zhang, Mario A. Gomez, Yu Ding, Shuhua Yao, Hongtao Lv, Xin Wang, Shaofeng Wang, Yongfeng Jia
Summary: The coprecipitation and aging of Fe(III)-As(III)-As(V)-SO4(2-) in acidic systems play a crucial role in controlling arsenic behavior. The study investigates the redistribution and transformation of arsenic in the system at different Fe/As molar ratios and pH values. Results show that As(III) contents in the solid products change with aging time and conditions, indicating the complex behavior of arsenic in the system.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Environmental Sciences
Lin Jin, Xing Xia, Chao He, Aminu Inuwa Darma, Yongfeng Hu, Mohsen Shakouri, Jianjun Yang
Summary: The study found that different C loadings can affect the specific surface areas and Cr(III) sorption capacities of the OFCs, and inner-sphere sorption dominates regardless of high or low C loadings. The wheat-DOC and maize-DOC induced OFCs exhibit differences in Cr(III) sorption capacities, which may be due to the higher carboxyl content in wheat-DOC. Cr K-edge XANES spectroscopy suggests that both Fh and organic fractions play a role in immobilizing Cr(III), with Fh fractions being significant.
Article
Environmental Sciences
Wenchao Meng, Xiaodi Li, Junxia Yu, Chunqiao Xiao, Haobo Hou, Ruan Chi, Guoqing Feng
Summary: Ferrihydrite-loaded water hyacinth-derived biochar (FH/WHBC) prepared by in-situ precipitation method showed a high adsorption capacity (116.8 mg/g) for glyphosate in wastewater treatment. The FH/WHBC maintained excellent adsorption performance under high acidity and presence of co-existing ions. It also demonstrated good regenerability and maintained high removal efficiency for glyphosate, reducing its concentration to a level lower than the Chinese groundwater quality standard. The adsorption mechanism was primarily attributed to electrostatic adsorption and the formation of inner-sphere complexes.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Soil Science
Jine Wei, Fenfen Zhang, Tangrong He, Jinzhou Du, Lijun Hou, Huan Feng
Summary: This study aimed to investigate the influence of organic carbon to iron molar ratio, ionic strength, and organic matter composition on the association of iron with organic matter. The results showed that different association modes, molar ratios, composition, and ionic strength affected the selective association of different organic matter components with iron oxide.
Article
Environmental Sciences
Xiaoming Zhao, Zidan Yuan, Shaofeng Wang, Guoqing Zhang, Shan Qu, Yidi Wang, Sijia Liu, Yuanming Pan, Jinru Lin, Yongfeng Jia
Summary: The ubiquitous co-existence of arsenic and cadmium presents a major challenge to the environment. This study found that the co-existence of arsenic and cadmium significantly delays the transformation rates of ferrihydrite, and alters the composition of transformation products. Additionally, the co-existent arsenic modifies the distribution of cadmium, reducing its mobility.
Article
Chemistry, Physical
Hui Li, Qun Jiang, Jiaxing Zhang, Yifan Wang, Ying Zhang
Summary: Biochar-supported phosphate-doped ferrihydrite (P-FH@BC) was prepared for simultaneous uptake of Pb(II) and Ce(III). The adsorption processes involve both physical and chemical adsorption mechanisms.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Engineering, Environmental
Nina C. Finlay, Caroline L. Peacock, Karen A. Hudson-Edwards, Karen L. Johnson
Summary: This study examines the ability of Fe-rich waste, water treatment residual (WTR), to adsorb Pb(II) in soils. Results show that Pb(II) primarily forms strong inner-sphere complexes with the ferrihydrite component of WTR, suggesting that Fe-rich WTR wastes could be effective adsorbents for Pb(II) in contaminated soils, contributing to sustainable terrestrial ecosystems.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Environmental Sciences
Kanfolo Franck Herve Yeo, Yingying Dong, Tongxuan Xue, Zhiwen Chen, Nan Zhang, Ye Yang, Liu Han, Meiling Liu, Ange Nsilani Kouediatouka, Hanse Pablick Patherny Lobo Mouguegue, Wendong Wang
Summary: Al-KBC was produced by pyrolysis of Al-modified kapok fibres, and its superior As(V) adsorption performance was observed due to better pore structures. The kinetics of As(V) adsorption followed the pseudo-second-order model and the adsorption mechanism corresponded to the Langmuir model. The adsorption reactions were spontaneous endothermic with a random approach at the adsorption interface, and the sorbent demonstrated satisfactory reusability.
ENVIRONMENTAL RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Chiara Abate, Giuseppe Cassone, Massimiliano Cordaro, Ottavia Giuffre, Viviana Mollica-Nardo, Rosina Celeste Ponterio, Franz Saija, Jiri Sponer, Sebastiano Trusso, Claudia Foti
Summary: This study comprehensively investigates the acid-base properties of carnosine and its interactions with Ca2+ and Mg2+, identifying thermodynamic parameters and complexation mechanisms using experimental techniques and theoretical approaches. The insights gained pave the way for the development of potential therapeutic applications of carnosine by revealing the mechanisms of action based on its interactions with metal cations such as Ca2+ and Mg2+.
NEW JOURNAL OF CHEMISTRY
(2021)
Article
Environmental Sciences
Ilhwan Park, Takashino Ryota, Takeuchi Yuto, Carlito Baltazar Tabelin, Theerayut Phengsaart, Sanghee Jeon, Mayumi Ito, Naoki Hiroyoshi
Summary: This study proposed a two-step process for immobilizing low concentration arsenic in wastewater, concentrating dilute arsenic solution through sorption/desorption using schwertmannite, and ultimately forming Ca-Fe-AsO4 compounds.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2021)
Article
Multidisciplinary Sciences
Fang Chen, Yaosheng Sun, Chao Liang, Tianyu Yang, Shican Mi, Yehong Dai, Molin Yu, Qiang Yao
Summary: The present study investigates the optimal preparation and adsorption conditions of biochar, as well as the adsorption characteristics and mechanisms of Cd2+ in water by biochar. The results show that corn stover biochar has potential applications for removing Cd2+ contamination in water.
SCIENTIFIC REPORTS
(2022)
Article
Chemistry, Analytical
Shupeng Lin, Ziqi Shen, Deng Pan, Rongting Ji, Yongrong Bian, Jiangang Han, Xin Jiang, Yang Song, Hu Cheng, Jianming Xue
Summary: Marine macroalgae can be used to prepare multielement-doped porous biochars, which have high sorption capacity and can effectively remove antibiotics from water. These excellent properties are attributed to the special composition and structure of biochars. Therefore, marine macroalgae have great potential as biomass resources.
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
(2023)
Article
Engineering, Environmental
Khondaker M. N. Alam, Evert J. Elzinga
Summary: Batch kinetic experiments combined with XAS were conducted to investigate the sorption behavior of Mn-(II), Co-(II), Ni-(II), Zn-(II), and Cd-(II) with sulfated green rust (GR) in anoxic suspensions at pH 8. The results showed that all five divalent metals coordinated at Fe-(II) sites of the GR sorbent. However, there were differences in the sorption behavior, with Mn-(II) and Cd-(II) showing limited uptake and Co-(II), Ni-(II), and Zn-(II) exhibiting extensive sorption throughout the experimental time frame. This was attributed to differences in affinity and extent of substitution in Fe-(II) sites of the GR lattice controlled by ionic size.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Engineering, Environmental
Anna Kubiak, Marcin Mackiewicz, Magdalena Biesaga, Marcin Karbarz
Summary: In this study, a temperature and pH sensitive microgel was synthesized and applied for the sorption of five bisphenols from aqueous solutions. The microgel showed satisfactory sorption capacity with maximum adsorption capacities ranging from 55 mg/g to 160 mg/g for all five bisphenols.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Oceanography
Zhang Mo, Zhao Yangguo, Wang Jinpeng, Bai Jie, Li Kuiran
Summary: This study compared the sorption isotherms and kinetics of SMT by corn biochars pyrolyzed at 300°C and 600°C under diverse pH conditions. It was found that the biochar 300C had higher sorption capacity and rate, and acid modified biochar showed better removal effect on SMT in solutions around pH 8.
JOURNAL OF OCEAN UNIVERSITY OF CHINA
(2021)
Article
Toxicology
Maori Kono, Tomoaki Okuda, Nami Ishihara, Hiroyuki Hagino, Yuto Tani, Hiroshi Okochi, Chiharu Tokoro, Masayuki Takaishi, Hidefumi Ikeda, Yasuhiro Ishihara
Summary: PM2.5 exposure can induce the release of chemokines in the skin, leading to neutrophil activation and an unregulated inflammatory reaction in the skin.
TOXICOLOGICAL RESEARCH
(2023)
Article
Automation & Control Systems
Chenzuo Ye, Yutaro Takaya, Yuki Tsunazawa, Kazuhiro Mochidzuki, Chiharu Tokoro
Summary: This study investigates the effect of agitator shape on grinding efficiency through experiments, kinetic analysis, and DEM simulations. The results show that the grinding rate constant of Agitator B is approximately 40% greater than that of Agitator A. The grinding modes in the two agitators are different, with surface grinding dominant in Agitator A and bulk grinding dominant in Agitator B.
INTERNATIONAL JOURNAL OF AUTOMATION TECHNOLOGY
(2022)
Article
Engineering, Electrical & Electronic
Yoshiki Egawa, Taketoshi Koita, Soowon Lim, Takao Namihira, Chiharu Tokoro
Summary: The development of efficient recycling technology for resin adhesives is necessary for accelerating the resource recycling of plastics and creating a recycling-oriented society. In this study, we utilized a fine wire explosion induced by an electric pulse to selectively separate different resin adherends. By applying a solvent and a silver wire to the interface of two resin plates and applying electric pulses, the separation of resin materials was achieved through gas expansion and wire vaporization.
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION
(2023)
Article
Physics, Fluids & Plasmas
Masataka Kondo, Taketoshi Koita, Soowon Lim, Takao Namihira, Chiharu Tokoro
Summary: This study characterized the state of a metal sphere in air and used pulsed discharge to cause an explosion of the sphere in the bonding adhesive, thereby separating the bonded structures. The results showed that adding a metal sphere to the adhesive allowed for selective separation of the adherend.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2022)
Article
Environmental Sciences
K. Tsuchiya, S. Fuchida, C. Tokoro
Summary: The study found that LDHs (layered double hydroxides) produced from magnesium oxide (MgO) and aluminum (Al) have good performance in removing hexavalent selenium (Se(VI)). By extending the hydration time of MgO and/or the reaction time of MgO-Al, Mg-Al LDHs with good Se(VI)-removal performance can be produced.
INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Chemical
Manabu Inutsuka, Masataka Kondo, Taketoshi Koita, Soowon Lim, Keisuke Ota, Tomoki Honda, Ryo Ogawa, Takao Namihira, Chiharu Tokoro
Summary: Facile techniques for debonding polymeric adhesives from metals are needed for material recycling. A promising solution is the pulsed discharge debonding method, where a high voltage pulsed discharge is applied to the system, resulting in rapid gas expansion and shock-wave emissions that debond the adhesive. However, the conventional method requires water, but this study successfully added filler to the adhesive to achieve effective pulsed discharge debonding. The threshold volume fraction of the filler for effective pulsed discharge inside the adhesive was determined based on experimental data and a percolation model.
JOURNAL OF ADHESION
(2023)
Article
Chemistry, Physical
Juan Qin, Sujuan Yuan, Mauricio Cordova-Udaeta, Keishi Oyama, Chiharu Tokoro
Summary: In this study, tobermorite was synthesized and used to remove Cd2+ from an aqueous solution. The synthesized tobermorite had a well-crystallized structure with a lot of mesopores and a large specific surface area. It could adjust the solution pH through the release of Ca2+ and OH- ions. The efficient removal of Cd2+ was achieved through surface complexation and ion exchange.
Article
Chemistry, Physical
Keishi Oyama, Kentaro Hayashi, Yusei Masaki, Takaya Hamai, Shigeshi Fuchida, Yutaro Takaya, Chiharu Tokoro
Summary: A passive treatment process using sulfate-reducing bacteria (SRB) was found effective in removing heavy metals from acid mine drainage (AMD), but the mechanism involved has been poorly understood. In this study, a sulfate-reducing column test was conducted with supplemental ethanol as an electron donor, and the reaction mechanism was investigated using geochemical modeling and X-ray absorption fine structure (XAFS) analysis. The results revealed that Cu was easily removed from the top surface of the column, while Zn and Cd depletion occurred in the middle of the column due to sulfide formation by SRB. Geochemical modeling and XAFS analysis confirmed the validity of the observation. These findings suggest that the developed geochemical model can be a useful tool in predicting heavy metal removal in AMD treatment with SRB.
Article
Engineering, Chemical
Yoshihiro Kosaku, Yuki Tsunazawa, Chiharu Tokoro
Summary: The discrete element method (DEM) is a reliable tool for analyzing powder processes, but it is computationally expensive for fine particle simulations. A promising solution is the use of coarse grain models, where multiple original particles are replaced with one large particle. This study proposes a new coarse grain model with a systematic parameter scaling law for adhesion forces, specifically liquid bridge forces. The simulation results agree well with the experimental results, demonstrating the superiority of the coarse grain model.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Chemical
Yuki Tsunazawa, Chiharu Tokoro, Yuji Ando, Tomoki Nakamura, Ryosuke Tsukimi, Nobuo Miyatake
Summary: This study demonstrates the applicability of gravity separation for the recycling of biodegradable plastics. The experimental results show that a laboratory-specific gravity separator achieves a high recovery ratio and purity for light-density plastics. Simulations further reveal that the separation efficiency is affected by particle size, but the gravity separator is still sufficient for the separation and recycling of biodegradable plastics.
JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
(2023)
Article
Engineering, Environmental
Aya Heiho, Izuru Suwa, Yi Dou, Soowon Lim, Takao Namihira, Taketoshi Koita, Kazuhiro Mochidzuki, Shinsuke Murakami, Ichiro Daigo, Chiharu Tokoro, Yasunori Kikuchi
Summary: This study conducted a prospective life cycle assessment to evaluate the effectiveness of proposed technologies for recycling photovoltaic panels. The technologies include aluminum frame separation, precise mechanical separation, hot-knife method for glass/ethylene-vinyl acetate separation, and high-voltage pulsed discharge for copper and silver recovery. Applying resource recovery technology reduces landfill waste and enables the reuse or recycle of glass. The high-voltage pulsed discharge produces a high concentration of copper that can be easily incorporated into smelting processes.
RESOURCES CONSERVATION AND RECYCLING
(2023)
Article
Engineering, Chemical
Yanhui Kong, Yutaro Takaya, Mauricio Cordova-Udaeta, Chiharu Tokoro
Summary: This study proposes a novel method for selective lithium extraction from spent ternary nickel-cobalt-manganese (NCM) LIBs using NaClO as an oxidant under near-neutral pH and oxidative conditions. The addition of NaClO is found to be essential for the selective extraction of lithium from the layered NCM structure under non-acidic conditions. Additionally, the oxidation by NaClO also induces cracking and phase transition of the spent cathode particles, enhancing lithium extraction efficiency. The proposed method is simple, safe, and cost-effective, making it attractive for practical application.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Article
Engineering, Environmental
Yutaro Takaya, Syuichi Kuwaba, Yusaku Tsujimura, Katsunori Yamaguchi, Chiharu Tokoro
Summary: All-solid-state lithium-ion batteries (ASS-LIBs) are expected to replace current liquid-based LIBs in the near future due to their high energy density and improved safety. However, it is yet to be determined if ASS-LIBs can be effectively recycled using the current recycling processes used for liquid-based LIBs.
Article
Green & Sustainable Science & Technology
Jifeng Xue, Keishi Oyama, Shigeshi Fuchida, Chiharu Tokoro
Summary: In this study, EDTA was used to control the effects of Mg(OH)(2) depression on the recoveries of chalcopyrite and pyrite, and to restrict Cu activation in pyrite flotation. The results showed that moderate EDTA dosages could potentially enable effective separation of chalcopyrite and pyrite.
JOURNAL OF SUSTAINABLE METALLURGY
(2023)
Article
Chemistry, Multidisciplinary
Hirokazu Narita, Motoki Maeda, Chiharu Tokoro, Tomoya Suzuki, Mikiya Tanaka, Hideaki Shiwaku, Tsuyoshi Yaita
Summary: In this study, the mechanism of Se(iv) and Se(vi) extraction from aqueous HCl solutions by EHBAA was investigated. The extraction behavior and structural properties of the dominant Se species in solution were examined. It was found that Se(vi) was reduced to Se(iv) in 8 M HCl, and around 50% of Se(vi) was extracted from 0.5 M HCl using 0.5 M EHBAA. On the other hand, Se(iv) was hardly extracted from 0.5 to 5 M HCl, but the extraction efficiency increased drastically above 5 M, reaching approximately 85%. The apparent stoichiometries of Se(iv) or Se(vi) to EHBAA were 1:1 and 1:2, respectively.