Article
Energy & Fuels
Anh Ngoc T. Cao, Cham Q. Pham, Tung M. Nguyen, Thuan Van Tran, Pham T. T. Phuong, Dai-Viet N. Vo
Summary: Dysprosium (Dy) promoted Co/Al2O3 catalysts with different Dy loadings were synthesized and found to enhance the basicity and activity of the catalysts for methane dry reforming. The addition of Dy reduced the crystallite size of Co3O4, resulting in better metal dispersion and higher catalytic performance. The optimal Dy loading was found to be 0.3 wt%, achieving the highest CH4 conversion and H-2 and CO yields.
Article
Chemistry, Physical
Zhoufeng Bian, Wenqi Zhong, Yang Yu, Zhigang Wang, Bo Jiang, Sibudjing Kawi
Summary: Catalysts of Ni supported on home-made mesoporous alumina exhibited high activity and stability in DRM, with NiAl2O4 spinel structure contributing to improved performance. Control of calcination temperature is crucial for catalyst properties.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Marcin Cichy, Monika Panczyk, Grzegorz Slowik, Witold Zawadzki, Tadeusz Borowiecki
Summary: Methane reforming with CO2 is a hot research topic due to the increasing demand for new hydrogen sources. In this study, a series of commercial nickel catalysts supported on a-Al2O3 and modified with different amounts of rhenium were investigated. The addition of rhenium positively influenced the stability and activity of the catalyst, and the formation of Ni-Re alloy played a significant role in enhancing its properties.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Multidisciplinary
Gaukhar E. Ergazieva, Moldir M. Telbayeva, Anna N. Popova, Zinfer R. Ismagilov, Kusman Dossumov, Laura K. Myltykbayeva, Vadim G. Dodonov, Sergey A. Sozinov, Almagul I. Niyazbayeva
Summary: Ni-Co/gamma-Al2O3 bimetallic catalysts were synthesized using solution combustion method, leading to higher methane conversion rates and suitability for low-temperature DRM reactions.
Article
Chemistry, Physical
Huayu Qiu, Jingyu Ran, Xin Huang, Zhiliang Ou, Juntian Niu
Summary: The study on six types of alumina-supported Ni catalysts revealed that proper preparation parameters and reaction conditions could increase the amount of Ni reduced from NiAl2O4, decrease the formation of inert carbon, and improve the catalyst performance.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Zahra Taherian, Vahid Shahed Gharahshiran, Fatemeh Fazlikhani, Mardali Yousefpour
Summary: In this study, the addition of samarium to Ni catalyst through impregnation method successfully decreased the average Ni crystallite size and specific surface area, resulting in improved catalytic activity, enhancing the methane dry reforming process.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Fernando Morales Anzures, Pastora Salinas Hernandez, Gilberto Mondragon Galicia, Albina Gutierrez Martinez, Francisco Tzompantzi Morales, Mario A. Romero Romo, Raul Perez Hernandez
Summary: The study found that different ZrO2 contents have different effects on the catalytic activity of the mixed oxide supports. For example, 5 wt% of ZrO2 in the catalyst led to an increase in medium strength basic sites and specific surface area, resulting in the best performance in DRM.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Zhoujie Liang, Yu Zhang, Guojie Zhang, Jun Liu, Yajing Cai, Ying Wang, Yuqiong Zhao, Guoqiang Li, Kunlun Bei
Summary: In this study, a series of cobalt catalysts modified by different lanthanide metals were synthesized using inexpensive industrial-grade alumina as a support for dry reforming of methane. The effect of lanthanide metals as accelerators of cobalt-based catalysts on catalytic performance and anti-coking properties was investigated. The results showed that lanthanide elements enhanced the electron transfer between cobalt species and lanthanide metal oxides, creating more active sites and improving the adsorption and activation of methane. Additionally, the presence of lanthanides promoted the adsorption and activation of carbon dioxide and the gasification of carbon accumulation, leading to improved anti-carbon accumulation performance. The prepared cobalt-lanthanum-based catalysts exhibited the best catalytic effect and have potential applications.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Applied
Marco Pizzolato, Giulia Da Pian, Elena Ghedini, Alessandro Di Michele, Federica Menegazzo, Giuseppe Cruciani, Michela Signoretto
Summary: The effects of vanadium promotion on gamma-alumina supported nickel catalysts for methane dry reforming were investigated. The introduction of vanadium was crucial to hinder catalyst deactivation by coke deposition. The formation of nanotubes was reduced and hydrogen yield increased. When coupled with calcium, selectivity toward hydrogen/syngas production was improved. Under concentrated gases, vanadium was fundamental for a higher activity, with an increase of 30% and 15% in CH4 and CO2 conversions compared with the non-doped catalyst.
Article
Chemistry, Physical
Robert Franz, Frans D. Tichelaar, Evgeny A. Uslamin, Evgeny A. Pidko
Summary: The study investigated the impact of passivation on the catalytic performance of Ni/Al2O3 catalysts in dry reforming of methane, showing that changes in conversion and coke content can track sintering of Ni particles. The study also revealed adverse effects of catalyst passivation in excess O2, leading to rapid local overheating and Ni sintering, even at small catalyst scales.
APPLIED CATALYSIS A-GENERAL
(2021)
Article
Chemistry, Applied
Yanan Diao, Haiyan Wang, Bingbing Chen, Li Wang, Xiao Zhang, Chuan Shi
Summary: Plasma-assisted dry reforming of methane is a promising method to produce syngas with unity H2/CO ratio. The design of efficient catalyst materials is of great importance to establish a match between CH4 and CO2 activation rates. Addition of La to the highly ordered mesoporous 10Ni5LaAl-one pot catalyst enhanced reducibility of Ni2+ species and promoted Ni dispersion, resulting in the highest catalytic activity and cokeresistance ability. Stability performance was achieved due to higher discharge power, efficient capacitance, and lower apparent activation energy of CO2 under plasma condition. A possible reaction mechanism was proposed for the 10Ni5LaAl-one pot catalyst during plasma-catalytic dry reforming process.
FUEL PROCESSING TECHNOLOGY
(2023)
Article
Energy & Fuels
Zongpeng Zou, Tao Zhang, Li Lv, Wenxiang Tang, Guoquan Zhang, Raju Kumar Gupta, Yan Wang, Shengwei Tang
Summary: Catalytic reforming for hydrogen production is important for sustainable energy, but coking is a challenge for industrialization. The key is to balance the formation rate of *C and *O. A novel preparation strategy of Ni-Co nano alloy catalysts was proposed, leading to highly dispersed nanoparticles. The bimetallic 5Ni5Co/SiO2 nano alloy catalyst showed the best catalytic activity, with stable performance and improved anti-coking properties.
Article
Chemistry, Multidisciplinary
Jung-Hyun Park, Tae-Sun Chang
Summary: The effect of a boron promoter on a Co-based catalyst in the dry reforming of methane was studied. It was found that an appropriate loading of boron reduced deactivation and coke deposition on the catalyst.
RESEARCH ON CHEMICAL INTERMEDIATES
(2022)
Article
Chemistry, Physical
Robert Franz, Donato Pinto, Evgeny A. Uslamin, Atsushi Urakawa, Evgeny A. Pidko
Summary: This study investigates the use of Ni/Al2O3 catalysts for dry reforming of methane, with a focus on the effects of different promoters on catalyst stability. Higher iron loading on the catalyst leads to lower coke formation during dry reforming. Additionally, promoters with high CO2 affinity can accelerate catalyst oxidation during regeneration, ultimately leading to sintering and increased coke formation. Promoters with significant CO2 interaction are more effective on sintered catalyst samples compared to unpromoted Ni/Al2O3.
Article
Chemistry, Physical
Wenqing Zeng, Li Li, Mouxiao Song, Xueshuang Wu, Guiying Li, Changwei Hu
Summary: This study finds that hydrogen treatment enhances catalytic activity and stability by forming small homogeneous nickel particles, while nitrogen and air treatment decreases activity and causes carbon accumulation.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Sean Najmi, Jungseob So, Eli Stavitski, William P. McDermott, Yimeng Lyu, Sam P. Burt, Ive Hermans, David S. Sholl, Carsten Sievers
Summary: Reactions of acetone and hydroxyacetone over heteroatom doped BEA zeolites (Sn, Mo, and W) with and without H2O vapor were studied using infrared spectroscopy. It was found that H2O vapor is beneficial in reducing coke formation at high temperatures, and Sn-BEA plays a significant role in catalyzing the conversion of acetone and hydroxyacetone.
Article
Chemistry, Multidisciplinary
Jennifer N. Jocz, Yimeng Lyu, Bryan J. Hare, Carsten Sievers
Summary: NiO/ceria-zirconia (CZ) is a promising catalyst for the selective oxidation of benzene, with Lewis-acidic NiO clusters activating C-H bonds and the redox-active CZ support supplying active oxygen species for the reaction. In this study, surface species formed from benzene, water, oxygen, phenol, and catechol on a NiO/CZ catalyst were examined using transmission in situ infrared (IR) spectroscopy. The presence of NiO clusters and the CZ support played crucial roles in benzene activation, leading to the formation of different surface species and indicating the potential of NiO/CZ for catalyzing the direct conversion of benzene to phenol with the addition of water enhancing the reaction process.
Article
Chemistry, Physical
Yubing Lu, Coogan Thompson, Chun-Te Kuo, Xiwen Zhang, Adam S. Hoffman, Alexey Boubnov, Simon R. Bare, Libor Kovarik, Hongliang Xin, Ayman M. Karim
Summary: The oxidation of CO on Pt group metals is influenced by the size of the metal and the reducibility of the oxide support. This study reveals that Ir supported on MgAl2O4, which is traditionally considered non-reducible, exhibits properties similar to reducible oxides when the Ir size is in the subnanometer range.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Chemistry, Physical
Mathew J. Rasmussen, Sean Najmi, Giada Innocenti, Andrew J. Medford, Carsten Sievers, J. Will Medlin
Summary: The (retro-)aldol condensation of acetaldehyde to crotonaldehyde was studied using supported molybdenum oxide catalysts. Highly dispersed MoOx catalysts exhibited optimal performance when supported on γ-Al2O3, while MoOx particles supported on SiO2 showed a monotonic relationship between Mo loading and condensation activity. Lewis acid site density and strength were important parameters for predicting activity. Weak acid sites had poor correlation with activity, while medium and strong acid sites showed good correlations. Partially reduced MoOx was more active for aldol condensation, but pretreatment in reducing or oxidizing environments had no significant effect on catalytic activity. Catalysts with high densities of strong acid sites tended to form more carbonaceous deposits on the surface during the reaction.
JOURNAL OF CATALYSIS
(2022)
Article
Chemistry, Physical
Laura L. Silva, Michael J. Stellato, Mariana V. Rodrigues, Bryan J. Hare, Jeffrey C. Kenvin, Andreas S. Bommarius, Leandro Martins, Carsten Sievers
Summary: This study illustrates the delamination of MCM-22 using shear forces in a vibratory ball mill, which results in comparable or improved physical properties compared to chemically delaminated MCM-22 without significant loss of acid sites. Mechanical treatment has a smaller effect on the initial rate of the model reaction for lignin-derived aromatics compared to chemical delamination, and it also shows improved deactivation resistance.
JOURNAL OF CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Andrew W. Tricker, Anuoluwatobi A. Osibo, Yuchen Chang, Jason X. Kang, Arvind Ganesan, Elisavet Anglou, Fani Boukouvala, Sankar Nair, Christopher W. Jones, Carsten Sievers
Summary: In this study, depolymerization of PET using mechanochemical hydrolysis was investigated. The results showed that the monomer yield of PET increased linearly with milling time, while the molecular weight decreased slightly. The influence of ball-to-powder mass ratio and milling frequency on depolymerization was also studied.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2022)
Article
Chemistry, Physical
Giada Innocenti, Stefan Emig, Lars Meyer, Matthias Mueller, Schirin Hanf, Stephan A. Schunk, Alois M. Kindler, Carsten Sievers
Summary: In situ infrared spectroscopy is used to study the hydrogenolysis of tetrahydrofurfuryl alcohol on Ru/SiO2 and SiO2. The key intermediate, hydroxy valeraldehyde, can undergo hydrogenation or the Tishchenko reaction. Both reactions produce 1,5-pentanediol, but the latter also produces hydroxyvaleric acid, which can polymerize on the catalyst surface.
Article
Chemistry, Physical
Andrew J. Medford, Carsten Sievers, Sean Najmi, Charles L. Liotta
Summary: The interaction between erythrose and various metal oxides was investigated using solid-state nuclear magnetic resonance spectroscopy. The impregnation of erythrose onto these oxides resulted in a shift in the equilibrium between cyclic, linear, and hydrated erythrose on the oxide surfaces. The effect of temperature on the surface species was dependent on the type of metal oxide.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Austin D. Winkelman, Vanessa Lebarbier Dagle, Teresa L. Lemmon, Libor Kovarik, Yong Wang, Robert A. Dagle
Summary: This paper discusses the enhanced catalytic performance of a 4Ag/4ZrO(2)/SBA-16 catalyst for ethanol conversion to butadiene through the addition of Na and K. While there is a slight decrease in conversion, the productivity is significantly increased with up to 50% improvement when 0.5% Na is added. The addition of Na or K reduces activity involving ethanol dehydration and results in higher butadiene selectivity.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Analytical
Mozhgan Akbari Alavijeh, Michael Schindler, Mark G. G. Wirth, Odeta Qafoku, Libor Kovarik, Daniel E. E. Perea
Summary: This study investigates the sequestration and transformation of silver (Ag) and arsenic (As) ions in soil organic matter (OM) at the nanoscale using advanced microscopy techniques. The results show that both Ag and As are predominantly sequestered by OM through various mechanisms, such as co-precipitation and adsorption on Fe-(hydr)oxides. The study also reveals the formation of different types of nanoparticles and their transformation processes.
ENVIRONMENTAL SCIENCE-PROCESSES & IMPACTS
(2023)
Article
Chemistry, Multidisciplinary
Van Son Nguyen, Yuchen Chang, Erin Phillips, Jacob A. DeWitt, Carsten Sievers
Summary: Mechanocatalytic oxidative cracking is used to overcome the chemical inertness of poly(ethylene) (PE) and Fe2O3-based Fenton system is employed to introduce oxygen-based functional groups to the PE backbone. The cleavage of polymer chain produces CO, CO2, O2, and H2O as byproducts, and the resulting fragments can be used as intermediates for fuel and sustainable chemical production.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Physical
Jacob A. DeWitt, Erin V. Phillips, Karoline L. Hebisch, Andrew W. Tricker, Carsten Sievers
Summary: Mechanocatalytic ammonia synthesis is a novel method for synthesizing ammonia under mild conditions. This study investigates the structural evolution of an in situ synthesized titanium nitride catalyst during extended milling. The yield of ammonia bound to the catalyst surface is strongly correlated with an increase in surface area during milling, but a lower surface concentration of ammonia at earlier milling times suggests a delay in ammonia formation, corresponding to the conversion of the titanium metal pre-catalyst into the nitride. Furthermore, the catalyst develops small pores due to interstitial spaces between agglomerated titanium nitride nanoparticles, which is observed through SEM and TEM. After milling for 18 hours, the catalyst nanoparticles appear to crystallize into a denser material, leading to a decrease in surface area and pore volume.
FARADAY DISCUSSIONS
(2023)
Article
Chemistry, Physical
Mengze Xu, Juan A. Lopez-Ruiz, Nickolas W. Riedel, Robert S. Weber, Mark E. Bowden, Libor Kovarik, Changle Jiang, Jianli Hu, Robert A. Dagle
Summary: Thermocatalytic decomposition (TCD) of methane using NiCu/CNT catalysts was studied for CO2-free hydrogen production and carbon co-product. The catalyst's activity and stability were influenced by the Ni/Cu ratio, metal particle size, and operating temperature. The carbon co-product mainly consisted of multiwalled carbon nanotubes (MWCNTs) with varying morphology depending on the Ni/Cu ratio and reaction temperature.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Analytical
Sarib Jadoon, Michael Schindler, Mark G. Wirth, Odeta Qafoku, Libor Kovarik, Daniel E. Perea
Summary: This study examines the sequestration of copper (Cu) by organic matter (OM) in forest soil near the Horne smelter in Canada. The research reveals that Cu is sequestered as nano- to micrometer-sized spinels, cuprite nanoparticles, and in association with magnetite nanoparticles in the OM matrix. A model is proposed to explain the sequestration process.
ENVIRONMENTAL SCIENCE-PROCESSES & IMPACTS
(2022)
Article
Chemistry, Physical
Fan Lin, Kenneth Rappe, Libor Kovarik, Miao Song, Xiaohong Shari Li, Mark Engelhard, Yong Wang
Summary: Research has found that high-temperature pretreatment of CeO2 support can enhance the redox and hydrocarbon oxidation activity of Pt/CeO2 catalyst. Compared to untreated CeO2 support, high-temperature pretreated CeO2 support can enhance the mobility of surface lattice oxygen, thus promoting the oxidation activity of Pt/CeO2 catalyst.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Xuemei Liu, Chaonan Cui, Shuoshuo Wei, Jinyu Han, Xinli Zhu, Qingfeng Ge, Hua Wang
Summary: This study presents a new strategy for designing efficient photocatalysts that can convert CO2 into hydrocarbons by utilizing synergistic catalytic sites. The findings provide a solution for the selective photocatalytic reduction of CO2 to CH4.
Article
Chemistry, Multidisciplinary
Chengxian Hu, Dan Wang, Lu Wang, Ying Fu, Zhengyin Du
Summary: A novel one-pot, three-component reaction conducted under electrochemical conditions was studied. The reaction involved 2-aminothiophenols, aldehydes, and malononitrile, using TBABF4 as an electrolyte and CuI as a catalyst. The proposed reaction mechanism suggested that CuI served as an electron relay. This method offers simplified operation, high atom economy, and mild reaction conditions.
Article
Chemistry, Multidisciplinary
Zhi Yang, Yu Chen, Linxi Wan, Yuxiao Li, Dan Chen, Jianlin Tao, Pei Tang, Fen-Er Chen
Summary: A highly enantioselective method for the complete hydrogenation of pyrimidinium salts using Ir/(S,S)-f-Binaphane complex as the catalyst was developed. This method provides easy access to fully saturated chiral hexahydropyrimidines, which are prevalent in many bioactive molecules. The reactions exhibit high yields and enantioselectivities under mild reaction conditions without additives. Successful application of this methodology in a continuous flow fashion further extends its practical utility.
Article
Chemistry, Multidisciplinary
Tina Jeoh, Jennifer Danger Nill, Wujun Zhao, Sankar Raju Narayanasamy, Liang Chen, Hoi-Ying N. Holman
Summary: In this study, the enzymatic hydrolysis of cellulose was investigated using real-time infrared spectromicroscopy. The spatial heterogeneity of cellulose was found to impact the hydrolysis kinetics. Hydration affected cellulose ordering, and Cel7A preferentially removed less extensively hydrogen bonded cellulose.
Article
Chemistry, Multidisciplinary
Tiphaine Richard, Walid Abdallah, Xavier Trivelli, Mathieu Sauthier, Clement Dumont
Summary: An effective method of grafting functionalities onto lignin based on glycerol carbonate has been developed using an efficient nickel-catalysed telomerisation reaction. This method allows lignin to have new reactive functions and reduces the glass transition temperatures of modified lignins, thereby expanding the application range of lignin-based resins.
Article
Chemistry, Multidisciplinary
Jing Qi, Xiyan Wang, Gan Wang, Srinivas Reddy Dubbaka, Patrick ONeill, Hwee Ting Ang, Jie Wu
Summary: This study presents a green and environmentally friendly approach for the synthesis of imides using electrocatalytic oxidation with H2O as the oxygen source. The method eliminates the need for toxic or expensive oxidants and achieves high yields under mild reaction conditions. It shows broad substrate compatibility and potential for industrial applications.
Article
Chemistry, Multidisciplinary
Babasaheb Sopan Gore, Lin-Wei Pan, Jun-Hao Lin, Yi-Chi Luo, Jeh-Jeng Wang
Summary: Here, we report a visible light-promoted intramolecular radical cascade reaction for the construction of fluorenol and naphthalene-fused cyclopropyl carbaldehyde derivatives. This method offers mild reaction conditions, a broad substrate scope, excellent step efficiency, and scalability, without the need for external chemical oxidants. The novelty of this protocol was demonstrated by synthesizing chrysene analogs and performing late-stage functionalizations.
Article
Chemistry, Multidisciplinary
Juho Antti Sirvio, Idamaria Romakkaniemi, Juha Ahola, Svitlana Filonenko, Juha P. Heiskanen, Ari Ammala
Summary: This article discusses the method of using supramolecular interaction between an aromatic hydrogen bond donor and lignin to achieve rapid delignification of softwood at low temperatures.
Article
Chemistry, Multidisciplinary
Yunyan Meng, Chunxiang Pan, Na Liu, Hongjiang Li, Zixiu Liu, Yao Deng, Zixiang Wei, Jianbin Xu, Baomin Fan
Summary: A novel visible light-driven synthesis method for 2,3-diamines has been developed, which has mild conditions, avoids the use of metal reagents, and can synthesize diamines and diols in one pot.
Article
Chemistry, Multidisciplinary
Mingqing Huang, Haiyang Huang, Mengyao You, Xinxin Zhang, Longgen Sun, Chao Chen, Zhichao Mei, Ruchun Yang, Qiang Xiao
Summary: A direct air-oxidized strategy for the synthesis of benzo[b]phosphole oxides was developed in this study. Arylphosphine oxides were transformed into phosphinoyl radicals, which were further combined with various alkynes to achieve the desired products. DFT calculations revealed the mechanism of phosphinoyl radical formation.
Article
Chemistry, Multidisciplinary
Anwei Wang, Jiayin Huang, Chunsheng Zhao, Yu Fan, Junfeng Qian, Qun Chen, Mingyang He, Weiyou Zhou
Summary: This study demonstrates an innovative strategy for the aerobic oxidation of C(sp(3))-H bonds using gamma-valerolactone. By optimizing the reaction conditions and utilizing specific catalysts, efficient oxidation of C(sp(3))-H bonds is achieved with good chemoselectivity in certain cases.
Article
Chemistry, Multidisciplinary
Shun Li, Likai Tong, Zhijian Peng, Bo Zhang, Xiuli Fu
Summary: Sulfide compounds show promise as electrocatalysts for water splitting, but their performance is limited by factors such as limited active sites and hindered substance transport. This study successfully prepared a high-entropy sulfide (ZnCoMnFeAlMg)(9)S-8, which reduced grain size and increased specific surface area, enabling the realization of a dual-functional catalyst with multiple catalytic sites. High entropy also modulated the electronic properties of sulfides, reducing the potential energy barrier for hydrolysis. This research introduces a new approach for functionalizing high entropy nanomaterials and improves the performance of water splitting catalysts.