Article
Chemistry, Applied
Dezhi Han, Qinghong Li, Enlai Wang, Wenpeng Xie, Guoliang Chen, Qinqin Zhang, Liancheng Bing, Fang Wang, Haitao Fu, Guangjian Wang
Summary: The microstructure changes of unsupported hydrodesulfurization catalysts were investigated in this study. The 3DOM NiMo unsupported catalysts were successfully fabricated using a PMMA colloidal crystal template and citric acid. The characterization results showed that these catalysts had a well-defined 3DOM structure, providing abundant active sites and high specific surface area, leading to improved catalytic performance. The 3DOM NiMo-1 catalyst exhibited excellent performance in thiophene conversion.
Article
Chemistry, Physical
Daria Ryaboshapka, Laurent Piccolo, Mimoun Aouine, Pascal Bargiela, Valerie Briois, Pavel Afanasiev
Summary: In this study, ultradispersed molybdenum-based catalysts were successfully prepared by sulfidation of thiomolybdates and showed higher HDS activity than conventional MoS2 reference catalysts. Mixing with cobalt further increased the turnover frequencies, exceeding those of benchmark CoMoS catalysts.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Materials Science, Multidisciplinary
Nertil Xhaferaj, Nicolo M. Ippolito, Fabio Maggiore, Francesco Ferella
Summary: The present study proposes a comprehensive recycling process for spent hydrodesulfurization (HDS) catalysts, successfully extracting molybdenum (Mo) and vanadium (V) and obtaining commercial-grade V2O5 and MoO3.
Article
Green & Sustainable Science & Technology
Sedat Ilhan, Dogukan Akgun
Summary: The leaching efficiency of spent Ni-Mo hydrodesulfurization catalyst was investigated by studying the effects of grinding, stirring speed, H2SO4 concentration, and temperature. The leaching behavior and kinetics of MoO3, NiMoO4, Al2O3, and AlPO4 from the spent catalyst were determined. The apparent activation energy values for the leaching of MoO3, NiMoO4, Al2O3, and AlPO4 in H2SO4 solutions were calculated.
JOURNAL OF SUSTAINABLE METALLURGY
(2021)
Article
Engineering, Environmental
Xiangyang Zhu, Qinling Bi, Liangrong Yang, Huifang Xing, Li Wang, Meng Rong, Shan Ni, Menglei Yuan, Congmei Chen, Huizhou Liu
Summary: Modification of alumina surface with thiol groups can adjust the metal-support interaction, leading to enhanced catalytic performance and stability of the catalyst, as demonstrated in this study where magnetic MoS2 nanoparticles supported on thiol groups grafted alumina showed excellent hydrodesulfurization efficiency and long-term stability.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Chemistry, Applied
A. Kokliukhin, M. Nikulshina, A. Mozhaev, C. Lancelot, C. Lamonier, N. Nuns, P. Blanchard, A. Bugaev, P. Nikulshin
Summary: A series of unsupported mono- and bimetallic MonW12-nS2 catalysts were synthesized by alumina elimination from supported MonW12-nS2/Al2O3 samples using acid etching. The unsupported MonW12-nS2 catalysts were found to be more effective in both naphthalene hydrogenation and dibenzothiophene hydrodesulfurization compared to the monometallic catalysts.
Article
Chemistry, Physical
Mohammad Reza Parvizi, Mehdi Ardjmand, Sajjad Habibzadeh
Summary: The addition of TiO2 to CoMo/Al2O3 catalyst has been found to enhance the catalytic performance by altering the support and active metal interaction, improving reducibility and surface acidity, and exhibiting good catalytic activity and selectivity in the hydrogenation of Pyrolysis Gasoline (PyGas).
Article
Materials Science, Multidisciplinary
Xin Liang, Junjie Tang, Laishi Li, Yusheng Wu
Summary: This paper presents a method for the comprehensive recovery of valuable metals from spent Al2O3-based catalysts by using sodium carbonate roasting and water leaching. The results show that roasting is a critical factor influencing the leaching effect, as it converts insoluble compounds into soluble ones. The recoveries of Al and V reach 99.64% and 99.24% respectively under the optimal leaching conditions. The metal composition in the leachate and residue favors metal recovery compared to direct recovery from the spent catalyst. The addition of stoichiometric Ba(OH)(2) allows for the selective recovery of V, followed by the recovery of Al and Ni through precipitation and calcination.
Article
Chemistry, Physical
Nicholas S. Sapienza, Kristin N. Knight, Malik Albrahim, Md. Raian Yousuf, Ayman M. Karim, John R. Morris
Summary: By studying the reaction mechanism of methanol oxidation on a Pt/TiO2 catalyst through experiments and surface science techniques, we found that methyl formate is produced under mild reaction conditions and fully combusted to CO2 at higher catalyst temperatures. Surface science experiments revealed that the production of CO2 involves a surface-bound formate intermediate through multiple proton-coupled electron-transfer steps. Importantly, we discovered that water generated during initial methanol adsorption plays a crucial role in unlocking the oxidative chemistry of the Pt-based material. These findings provide valuable insights for modifying catalysts to selectively enhance partial or full oxidation, enabling the production of valuable commodity chemicals.
Article
Chemistry, Physical
Uddhav Kanbur, Ryan J. Witzke, Jiayi Xu, Magali S. Ferrandon, Timothy A. Goetjen, A. Jeremy Kropf, Frederic A. Perras, Cong Liu, T. Don Tilley, David M. Kaphan, Massimiliano Delferro
Summary: A series of electrophilic organoruthenium complexes were synthesized and applied to selective hydrosilylation of olefins. Material 4 showed good catalytic activity and selectivity, and could be recycled multiple times without significant loss of activity.
Article
Materials Science, Multidisciplinary
Jothi Ramalingam Rajabathar, Hamad A. Al-Lohedan, Selvaraj Arokiyaraj, Zuheir A. Issa, Chandra Sekhar Dash, Sundararajan Murugesan, Shaik K. Khadheer Pasha, Dhaifallah M. Al-dhayan, Jimmy Nelson Appaturi
Summary: The pure rutile phase of titania nanoparticles was prepared by a strong acidic sol-gel process followed by a hydrothermal treatment. The critical parameters for particle size and crystallinity were optimized reaction conditions and precursor usage. XRD and Raman spectroscopy confirmed the formation of the pure rutile phase, while SEM and TEM images showed the unique morphology and small particle sizes of the prepared R-TiO2.
Article
Multidisciplinary Sciences
Zhuan Chen, Faliang An, Yayun Zhang, Zhiyan Liang, Wenyuan Liu, Mingyang Xing
Summary: We report on a bimetallic Co-Mo single-atom catalyst (SAC) that shows excellent performance in activating peroxymonosulfate (PMS) for sustainable degradation of organic pollutants. The Mo sites in Mo-Co SACs play a critical role in conducting electrons from organic pollutants to Co sites, leading to a significant increase in the degradation rate of phenol. The bimetallic SACs exhibit excellent catalytic performance even under extreme conditions, efficiently degrading 600 mg/L of phenol and showing negligible toxicity.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Acoustics
Zohal Safaei Mahmoudabadi, Alimorad Rashidi, Ahmad Tavasoli, Mehdi Esrafili, Mohammad Panahi, Mojtaba Askarieh, Saeed Khodabakhshi
Summary: A novel method using ultrasonication was developed to synthesize highly porous MoS2/graphene oxide (M-GO) nanocomposites, leading to increased specific surface area and improved HDS activity. Various characterization techniques were utilized to study the physicochemical properties and catalytic performance of the nanocatalysts, with high surface area M9-GO nanocatalyst showing the best catalytic performance compared to traditional catalyst Co-Mo/gamma Al2O3. Additionally, density functional theory calculations revealed that the GO substrate can stabilize MoS2 layers, promoting the direct desulfurization reaction in the hydrodesulfurization process.
ULTRASONICS SONOCHEMISTRY
(2021)
Article
Engineering, Chemical
Hui Shang, Chong Guo, Pengfei Ye, Wenhui Zhang
Summary: The study shows that modification, especially under microwave treatment, can significantly enhance the performance of CoMo/γ-Al2O3 catalysts, reduce the interaction between active components and supports, thereby improving HDS performance and olefin selectivity.
FRONTIERS OF CHEMICAL SCIENCE AND ENGINEERING
(2021)
Article
Energy & Fuels
Gesha Desy Alisha, Wega Trisunaryanti, Akhmad Syoufian, Savitri Larasati
Summary: The study focused on hydrocracking waste palm oil over Mo/SiO2 catalyst, with Mo(C)/SiO2 showing excellent performance in producing biofuel with high hydrocarbon content. The catalyst exhibited high acidity and conversion rate, making it suitable for repeated use.
BIOMASS CONVERSION AND BIOREFINERY
(2021)
Article
Chemistry, Applied
Yudai Shirasaki, Hiroyuki Nasu, Tadanori Hashimoto, Atsushi Ishihara
FUEL PROCESSING TECHNOLOGY
(2019)
Article
Chemistry, Applied
Atsushi Ishihara, Akira Andou, Tadanori Hashimoto, Hiroyuki Nasu
FUEL PROCESSING TECHNOLOGY
(2020)
Article
Energy & Fuels
Atsushi Ishihara, Shinya Matsuura, Fumiya Hayashi, Kouki Suemitsu, Tadanori Hashimoto
Article
Chemistry, Multidisciplinary
Atsushi Ishihara, Kentarou Takai, Tadanori Hashimoto, Hiroyuki Nasu
Article
Chemistry, Analytical
Atsushi Ishihara, Masashi Ninomiya, Tadanori Hashimoto, Hiroyuki Nasu
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
(2020)
Article
Chemistry, Physical
Shinya Matsuura, Tadanori Hashimoto, Atsushi Ishihara
Summary: Novel alumina and titania modified by silica were prepared using the GSR method, resulting in the observation of new acid sites. The mixed catalysts showed higher conversion and improved gasoline fraction selectivity compared to single-component catalysts.
APPLIED CATALYSIS A-GENERAL
(2021)
Article
Chemistry, Multidisciplinary
Tadanori Hashimoto, Kentaro Takai, Hung Viet Quang Nguyen, Masakatsu Nomura, Atsushi Ishihara
Summary: Results showed that Upper Freeport formed mullite-related substances in air, while Illinois #6 produced similar substances in air after carbonization under Argon. The presence of Al/Si ratio and lime content affected the formation of mullite-related substances in the ash components.
Article
Chemistry, Applied
Atsushi Ishihara, Yuuta Kodama, Tadanori Hashimoto
Summary: Composite catalysts were prepared using mesoporous alumina as a matrix and Ga-exchanged ZSM-5 as a major catalytic component, with investigations into their effects on the activity and selectivity of aromatics from cracking and dehydrocyclization of n-pentane. Experimental results using a fixed bed reactor showed that increasing temperature led to higher conversion of n-pentane and selectivity for aromatics.
FUEL PROCESSING TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Atsushi Ishihara, Shouhei Kanamori, Tadanori Hashimoto
Summary: Under moderate pressure and temperature conditions, the addition of Zn increases the yield of aromatics, while catalysts without Zn produce more products with more than C18.
Article
Energy & Fuels
Atsushi Ishihara, Kanji Takemoto, Tadanori Hashimoto
Summary: The study found that an increase in alumina content and metal content can enhance hydrocracking activity, but a decrease in metal content can lead to an increase in diesel component. A proper combination of alumina-supported NiMo sulfide and Zn-exchanged ZSM-5 can increase the yield of aromatics.
Article
Chemistry, Analytical
Tadanori Hashimoto, Keisuke Nakade, Atsushi Ishihara, Yuji Nishio
Summary: The study investigated the feasibility of Ag2O-TeO2 glasses as reference electrodes for pH sensors. The pH sensitivity of Ag2O-TeO2 glasses increased with higher Ag2O content, but remained below 40%, making them potential candidate reference electrodes for pH sensors. The heat-treated 25Ag2O center dot 75TeO2 glass and 25Ag2O center dot 75TeO2 glass/stainless steel electrodes showed relatively low pH sensitivities of 26% and 5%, indicating their suitability for pH sensor applications.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Chemistry, Multidisciplinary
Atsushi Ishihara, Yuu Tsuchimori, Tadanori Hashimoto
Summary: Dehydrocyclization-cracking of methyl oleate using ZnZSM-5-Al2O3 hierarchical composite-supported Pt catalysts yielded aromatics and valuable fuels, with Pt addition method significantly affecting catalyst reactivity. The method of Pt introduction did not impact catalyst pore structure.
Article
Chemistry, Multidisciplinary
Atsushi Ishihara, Hiroshi Tsujino, Tadanori Hashimoto
Summary: Novel carbon-Al2O3 and carbon-ZrO2 composite-supported Co catalysts were prepared using the sol-gel method with the addition of CeO2 investigated on the steam reforming of ethanol. While CeO2 addition had minimal effect on catalysts with Al2O3, it enhanced the conversion and hydrogen yield for catalysts with ZrO2, with 16Co42C31.5Ce10.5Zr exhibiting the highest hydrogen yield at 600 degrees C.
Article
Chemistry, Physical
Atsushi Ishihara, Kouki Mori, Kazuya Mori, Tadanori Hashimoto, Hiroyuki Nasu
CATALYSIS SCIENCE & TECHNOLOGY
(2019)
Article
Multidisciplinary Sciences
Tadanori Hashimoto, Hiroki Kitabayashi, Kenta Ito, Hiroyuki Nasu, Atsushi Ishihara, Yuji Nishio