Article
Materials Science, Ceramics
Ming Hao, Peizhang Gao, Wei Liu, Baizeng Fang, Jinsheng Liang, Tingting Zhang, Youpeng Ding, Hui Zhang, Fei Wang
Summary: A novel Co/CoAl2O4/sepiolite nanocomposite was synthesized in this study, with optimal conditions identified for fabrication. The nanocomposite showed fine cobalt nanoparticles anchored on the surface of CoAl2O4, leading to higher selectivity for high-carbon hydrocarbons in Fischer-Tropsch synthesis. This work provides an effective strategy for low-cost batch fabrication of efficient cobalt-based catalysts.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Multidisciplinary
Esteban Gioria, Liseth Duarte-Correa, Najmeh Bashiri, Walid Hetaba, Reinhard Schomaecker, Arne Thomas
Summary: A facile and rational approach was used to synthesize bimetallic heterogeneous tandem catalysts, utilizing core-shell structures to control ensembles of different nanoparticles for chemocatalytic reactions. Successful tandem processes were achieved in CO2 hydrogenation to methane and light olefins.
NANOSCALE ADVANCES
(2021)
Article
Chemistry, Physical
Yanbing Li, Yingluo He, Kensei Fujihara, Chengwei Wang, Xu Sun, Weizhe Gao, Xiaoyu Guo, Shuhei Yasuda, Guohui Yang, Noritatsu Tsubaki
Summary: In this study, a core-shell structured Na/Fe@Co bimetallic catalyst was developed to enhance CO2 conversion and selectivity of light hydrocarbons, while inhibiting CO selectivity. Characterization analyses revealed that the introduction of CoCo Prussian Blue Analog (CoCo PBA) increased the reducibility of iron oxide, accelerated the formation of iron carbide, and adjusted the surface basic properties of the catalyst. Additionally, trace Co atoms acted as a second active center in the CO2 Fischer-Tropsch synthesis process for increasing the synthesis of light hydrocarbons from CO hydrogenation. This work provides a novel core-shell structured bimetallic catalyst system for the production of light hydrocarbons, particularly light olefins, from CO2 hydrogenation.
Article
Green & Sustainable Science & Technology
P. Jain, M. Chimote, C. P. Vinod
Summary: Bimetallic nanoparticles with synergistic effects can enhance the catalytic activity, selectivity, and stability of solid materials. The study synthesized Au@Co core-shell bimetallic nanoparticles and demonstrated efficient and stable CO conversion in the FT reaction.
MATERIALS TODAY SUSTAINABILITY
(2021)
Article
Chemistry, Applied
Prasad Gonugunta, A. Iulian Dugulan, G. Leendert Bezemer, Ekkes Bruck
Summary: Operando spectroscopic techniques were used to investigate the impact of oxygenates deposition on the deactivation of cobalt on titania Fischer-Tropsch catalysts under high pressure. It was found that catalysts prepared via impregnation had more and heavier carboxylates, likely due to higher olefin content in the products, leading to increased formation of oxygenates. Gas chromatography/infrared spectroscopy data indicated that the surface carboxylate species were not involved in catalyst deactivation, serving as spectator species on the titania support.
Article
Chemistry, Physical
Caiping Ma, Wei Zhang, Qiang Chang, Xianzhou Wang, Hulin Wang, Huimin Chen, Yuxue Wei, Chenghua Zhang, Hongwei Xiang, Yong Yang, Yongwang Li
Summary: By modulating pyrolysis temperature, catalysts with different carbon shells (amorphous carbon, graphene or graphite shells) coated theta-Fe3C and/or alpha-Fe nanoparticles are acquired. It is found that O-Fe3C is confirmed to be FTS active with superior CAC chain growth ability, showing higher C5+ selectivity and lower CH4 selectivity. Meanwhile, graphene shell inhibits iron nanoparticles aggregation and stabilizes the catalysts.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Physical
Jane N. Agwara, Nikki J. Bakas, Michael L. Neidig, Marc D. Porosoff
Summary: Fe-based catalysts encapsulated within ZSM-5 exhibit improved selectivity towards desired light olefins in Fischer-Tropsch synthesis. While the encapsulation process may destabilize the Fe-based active phase, the core-shell catalysts demonstrate enhanced performance compared to the control samples.
Article
Chemistry, Physical
Tobias F. Kimpel, Jin-Xun Liu, Wei Chen, Robert Pestman, Emiel J. M. Hensen
Summary: Through IR spectroscopy and DFT calculations, it has been discovered that in the Fischer-Tropsch reaction, Mn promotes a silica-supported Co catalyst with a MnO layer covering the Co surface, activating adsorbed CO through reaction with an oxygen vacancy. This results in higher activity, higher CHx coverage, increased C5+ selectivity, and decreased CH4 selectivity. Increasing pressure amplifies the selectivity differences. However, above around 4 bar, the addition of Mn decreases C5+ selectivity, possibly due to its promotion of C-O bond dissociation but not chain growth. Migration of formed monomers for chain growth on the Co surface may be hindered by high CO coverage, especially at high pressure.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Physical
C. J. (Kees-Jan) Weststrate, Daniel Garcia Rodriguez, Devyani Sharma, J. W. (Hans) Niemantsverdriet
Summary: This study investigates the interaction between hydrogen and cobalt surfaces, revealing the adsorption and desorption behavior of hydrogen on different surface structures. It also discovers the variation of hydrogen adsorption strength and equilibrium constant under different conditions.
JOURNAL OF CATALYSIS
(2022)
Article
Chemistry, Physical
F. Platero, S. Todorova, L. Aoudjera, L. Michelin, B. Lebeau, J. L. Blin, J. P. Holgado, A. Caballero, G. Colon
Summary: In this study, cobalt catalyst supported on mesostructured TiO2 was prepared and subjected to calcination and reduction. The results showed that cobalt nanoparticles were uniformly distributed along the mesopore channels of TiO2, and the highly stable metal active sites contributed to the generation of C5+ products in Fischer-Tropsch synthesis reaction.
ACS APPLIED ENERGY MATERIALS
(2023)
Article
Energy & Fuels
Francisco Platero, Alfonso Caballero, Gerardo Colon
Summary: Cobalt supported TiO2 catalysts were prepared by wet-impregnation and by immobilization over APTES grafted TiO2. The impregnated system showed better catalytic performance after reduction at 260 degrees C, but significant deactivation was observed. In contrast, the functionalized catalyst showed better catalytic performance after reduction at 400 degrees C with notable stability. CO-DRIFT operando analysis revealed that the impregnated system was strongly affected by negative SMSI upon reduction at higher temperature, while immobilization on APTES hindered the loss of metal active sites. The study of spent catalysts indicated that Co was redispersed in the impregnated catalyst while functionalized catalyst tended to form agglomerates.
Article
Energy & Fuels
Dalia Liuzzi, Francisco J. Perez-Alonso, Sergio Rojas
Summary: Ru-Co/Al2O3 and Ru-Fe/Al2O3 catalysts prepared by reduction-deposition method exhibit high activity in Fischer-Tropsch Synthesis, showing different conversion rates and product selectivity. The interaction between Ru and Co in Ru-Co/Al2O3 enhances the activity, while Ru-Fe/Al2O3 displays superior initial performance but declines over time, with less enriched products compared to Ru/Al2O3.
Article
Chemistry, Applied
Farnaz Yousefian, Mokhtar A. Babatabar, Melika Eshaghi, Soodabeh Morovati Poor, Ahmad Tavasoli
Summary: The performance of bio chars made from Rice husk, Coconut shell, and Cladophora glomerata algae as Fischer-Tropsch synthesis (FTS) cobalt catalyst support was examined. The biochars were produced by pyrolysis process and activated at specific temperature and time. 15 wt% cobalt catalysts were prepared through impregnation method. The physicochemical properties of the catalysts were analyzed using various techniques. The catalytic performance of biochars supported cobalt catalysts was compared with gamma-Alumina supported industrial catalyst, and the modified algae biochar supported cobalt catalyst showed the highest FTS rate and CO conversion rate with a slight decrease in C5+ liquid hydrocarbons selectivity.
FUEL PROCESSING TECHNOLOGY
(2023)
Article
Chemistry, Physical
Lebohang Macheli, Emanuela Carleschi, Bryan P. Doyle, Gerard Leteba, Eric van Steen
Summary: Metal-support interactions in inverse catalysts prepared by adsorbing TEOS on Co3O4 can be manipulated by varying the solvent mixture. Deposition of TEOS on Co3O4 nanoparticles in n-hexane results in the formation of silica oligomers interacting strongly with cobalt(II,III)oxide after calcination at 573 K. Modification of Co3O4 nanoparticles with TEOS in a hydrolysing environment results in a stronger interaction due to the formation of surface cobalt silicate through hydrolysis.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Physical
Madita Einemann, Simon Haida, Nico Fischer, Nattawut Osakoo, Jatuporn Wittayakun, Frank Roessner
Summary: The role of cobalt chloride hexahydrate as a precursor of cobalt bulk catalysts was investigated for the Fischer-Tropsch reaction. Different oxygen-containing cobalt compounds were detected through in situ DRIFTS, in situ XANES, in situ XRD, and inverse TPR techniques. The reaction network of cobalt chloride transformation was discussed, taking into account the back mixing in different geometries of measuring cells. The choice of catalyst activation procedure is important for the formation of cobalt oxide and subsequent activity in the Fischer-Tropsch reaction.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Fangmin Chen, Tianliang Li, Huijuan Zhang, Madiha Saeed, Xiaoying Liu, Lujia Huang, Xiyuan Wang, Jing Gao, Bo Hou, Yi Lai, Chunyong Ding, Zhiai Xu, Zuoquan Xie, Min Luo, Haijun Yu
Summary: This study discovered that iron oxide nanoparticles (IONPs) can significantly enhance the production of type-I interferon (IFN-I) and achieve a dosage-sparing effect when combined with the STING agonist MSA-2. Acid-ionizable copolymers are coassembled with IONPs and MSA-2 to concentrate STING activation in lymph nodes and improve antigen cross-presentation. The iron nanoadjuvant PEIM effectively delivers antigens to antigen-presenting cells (APCs) and induces a potent and durable antitumor immune response.
ADVANCED MATERIALS
(2023)
Article
Engineering, Environmental
Min Yan, Yang Rong, Feng Wu, Zhixiong You, Dashan Wang, Xudong Yang, Zhengping Hao, Jinjun Li, Zhongshen Zhang
Summary: Porous graphitized carbon fibers (PGCFs) with enhanced hydrophobicity were prepared by catalytic graphitization of ACFs. They showed high adsorption capacity for toluene, cyclohexane, and ethanol, and even increased adsorption of ethanol under humid conditions. The 7C electrons and high polarizability of PGCFs strengthened their interaction with non-polar organics, and capillary condensed water in mesopores acted as absorbate for polar ethanol.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Environmental Sciences
Hao Wang, Yongrong Zou, Wenyu Wang, Yihui Zhang, Gilles Mailhot, Jinjun Li, Feng Wu, Liting Luo
Summary: This study determined the photocatalytic degradation behavior of aromatic micro-pollutants (AMPs) and developed a quantitative structure-activity relationship (QSAR) model for predicting the photooxidation reaction of AMPs. The model revealed that the single electron transfer pathway and adsorption were the significant steps in the reaction process, and electron-donating substituents promoted the photooxidation of AMPs. This research provides guidance for studying the mechanism and selective oxidation of AOPs photooxidation system based on graphene oxide (GO).
Article
Energy & Fuels
Yaqian Liu, Cong Pan, Yongrong Zou, Feng Wu, Zhixiong You, Jinjun Li
Summary: A facile colloidal deposition method was used to fabricate silica-supported Fe2O3 nanoparticles, and their catalytic performances in FTO were studied. The catalyst with a loading of 30.4% and a particle size of 4.7 nm showed the highest selectivity and stability.
Article
Remote Sensing
Junsheng Ding, Junping Chen, Jungang Wang, Yize Zhang
Summary: This study calculates and compares the bias and standard deviation of tropospheric delay for approximately 7000 selected GNSS stations in 2020 with the NWM data. The results show positive biases of approximately 4 mm in the NGL zenith tropospheric delay relative to the NWM over most of the globe, with a seasonal amplitude reaching 6 mm in the bias and an antenna-related mean bias of approximately 1.6 mm in the NGL tropospheric delay. These findings can be used to provide prior tropospheric delays with appropriate uncertainties and to assess the suitability of using NWMs for real-time positioning solutions.
Article
Biochemistry & Molecular Biology
Juntao Guo, Yihui Zhang, Jinjun Li, Feng Wu, Liting Luo
Summary: This study developed a pyrite-based photo-Fenton system using citric acid and simulated/natural sunlight, which could generate H2O2 in situ through enhanced activation of molecular oxygen, for the degradation of pollutants. The system showed high efficiency in degrading acetaminophen under both xenon lamp and natural sunlight irradiation.
Article
Remote Sensing
Bobin Cui, Xinyuan Jiang, Jungang Wang, Pan Li, Maorong Ge, Harald Schuh
Summary: Introducing precise atmosphere information into precise point positioning enables rapid ambiguity resolution and significant accuracy improvement, but only in regions with dense networks and stable communication links. To address the conflict between correction accuracy and the amount of atmosphere information for larger areas, a hierarchical augmentation mode is developed, combining the advantages of fitting and region interpolation models to relieve communication burden. Experimental results show that the proposed mode satisfies real-time positioning convergence requirements and significantly reduces massive corrections in communication.
Article
Engineering, Environmental
Yi Wu, Xingyun Huang, Jing Xu, Wenyu Huang, Jinjun Li, Gilles Mailhot, Feng Wu
Summary: This study observed that natural organic matter (NOM), especially humic substances (HSs) and low molecular weight carboxylic acids (CAs), inhibited the photooxidation of As(III) in the CFH-As(III) system, and the inhibition varied with NOM concentration. Statistical analysis using experimental data and a calculation model showed that the Freundlich model provided a better description of this inhibition.
Article
Environmental Sciences
Zhiwei Qin, Qin Zhang, Guanwen Huang, Longjiang Tang, Jungang Wang, Xiaolei Wang
Summary: In this study, a novel real-time and postprocessing method for detecting orbit maneuvers of BeiDou satellites is proposed. This method compares the epoch-updated orbit and predicted orbit during non-maneuver period, as well as the orbital state difference during maneuver and non-maneuver periods. It has advantages over using observation residuals and improves the accuracy and timeliness of orbit maneuver detection. 32 orbit maneuver events of BeiDou satellites were successfully detected in 2022 using this method.
Article
Environmental Sciences
Fangfang Cao, Li Tan, Jinghua Shi, Jinjun Li, Xiuyan Xu, Ye Chen, Fengju Zhang, Xihua You
Summary: Between 9 July and 19 August 2016, the air concentrations of 57 volatile organic compounds (VOCs) were measured in Shandong Province, eastern China. The study aimed to investigate the characteristics, ozone formation potential, and main sources of VOCs. The results showed that alkenes and aromatics were the most active species in ozone formation, and local emissions were the main sources of VOCs in Shandong Province.
Article
Remote Sensing
Longjiang Tang, Jungang Wang, Bobin Cui, Huizhong Zhu, Maorong Ge, Harald Schuh
Summary: Global Navigation Satellite Systems (GNSS) Real-time Precise Point Positioning (RT-PPP) heavily relies on precise satellite orbits and clocks, particularly the latter requiring high update rate. New constellations like Galileo and BDS-3 with stable hydrogen clocks onboard enable longer arc prediction. Multi-GNSS ultra-rapid precise orbit determination allows half-hourly update, achieving 3D accuracy of 2.9 and 11.3 cm for static and kinematic solutions, respectively. Galileo satellites contribute the most in the quad-constellation solution due to highly stable satellite clocks.
Article
Remote Sensing
Zhilu Wu, Cuixian Lu, Xinjuan Han, Yuxin Zheng, Bo Wang, Jungang Wang, Yanxiong Liu, Yang Liu
Summary: In this study, the real-time retrieval of precipitable water vapor (PWV) using shipborne GNSS kinematic precise point positioning (PPP) solutions was investigated. Results show that Beidou performs comparably to Galileo in PWV retrieval, surpassing GLONASS but slightly inferior to GPS. The accuracy of Beidou in comparison to ERA5 PWV products is 3.19 mm, with an average initialization time of 43.9 min. Furthermore, the real-time multi-GNSS PWV achieves an accuracy improvement of more than 15% compared to single-constellation resolutions, reaching an accuracy of 2.34 mm.
Article
Green & Sustainable Science & Technology
Minjuan Cai, Peng Cheng, Jinjun Li, Feng Wu, Mohamed Sarakha, Gilles Mailhot, Marcello Brigante
Summary: In this study, nano zero-valent iron catalysts supported on graphitized carbon (GC-nZVI) were used to efficiently degrade BPA under neutral pH conditions. The catalyst showed a significant synergistic effect, increasing the degradation efficiency of BPA under both dark and UVA conditions.
JOURNAL OF CLEANER PRODUCTION
(2023)
Article
Chemistry, Physical
Cong Pan, Wenyu Wang, Chenchong Fu, Jong Chol Nam, Feng Wu, Zhixiong You, Jing Xu, Jinjun Li
Summary: A wet scrubber utilizing FeOCl-loaded biomass-derived activated carbon has been developed for the efficient removal of chlorinated volatile organic compounds (CVOCs) from air. The system performs well at low pH and H2O2 concentrations, and can remove over 90% of various CVOCs. The study also proposes a degradation pathway for dichloroethane and suggests the potential for designing catalysts based on biomass structures for wet oxidation of CVOCs or other contaminants.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Geochemistry & Geophysics
Longjiang Tang, Jungang Wang, Huizhong Zhu, Maorong Ge, Aigong Xu, Harald Schuh
Summary: In this study, a new efficient precise orbit determination strategy called epoch-parallel processing is presented. By splitting the processing job into sub-sessions and parallel processing, the orbit update latency is reduced, resulting in a halving of the time-consuming. The method is effective in improving orbit quality and can be implemented for any batch-based GNSS processing.
JOURNAL OF GEODESY
(2023)
