Article
Chemistry, Physical
Juxue Wang, Ling Zhang, Di Zeng, Wenjing Wang, Ruofan Li, Taikang Jia, Bingkun Cui, Hongxiang Chu, Wenzhong Wang
Summary: In this study, a composite photocatalyst (Ag/AgCl-WO3-x) was constructed to achieve one-step photocatalytic conversion of CH4 to CH3COOH without carbonyl species. Chlorine radicals and hydroxyl radicals were simultaneously produced over Ag/AgCl under light irradiation. By combining WO3-x, carbon-carbon coupling reaction between carbonyl and methyl species occurred to effectively produce CH3COOH.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Chemistry, Physical
Chen -Wei Wang, Yuan Sun, Li-Jun Wang, Wen-Hua Feng, Yu -Ting Miao, Ming -Ming Yu, Yu-Xuan Wang, Xu-Dong Gao, Qingqing Zhao, Zhiqin Ding, Zhaochi Feng, Si-Min Yu, Jinhui Yang, Yongfeng Hu, Jian-Feng Wu
Summary: Herein, we report a direct co-conversion of methane, carbon monoxide, and hydrogen peroxide into acetic acid, catalyzed by Fe/ZSM-5 (0.25) zeolite under mild conditions, achieving a high acetic acid yield with optimal selectivity. C-13-Tracking experiments revealed the origin of methyl and carbonyl groups in acetic acid. Spin-trapping experiments indicated the involvement of center dot OH and center dot CH3 radicals. In situ Raman analysis suggested a potential intermediate -Fe-OCH3 species. Overall, our method is greener and more economical, showing potential as an industrial alternative.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Chemistry, Multidisciplinary
Juliette Karpiel, Pierre Lonchambon, Frederic Dappozze, Ileana Florea, Diana Dragoe, Chantal Guillard, Nathalie Herlin-Boime
Summary: In an attempt to produce alkenes efficiently, a photocatalytic process has been developed to selectively obtain ethylene from propionic acid degradation. Copper oxide-modified titanium dioxide nanoparticles were synthesized using laser pyrolysis, and the synthesis atmosphere strongly influenced the morphology and selectivity of the photocatalysts towards different hydrocarbons and H2 products. Under a helium environment, highly dispersed copper species in CuxOy/TiO2 promoted the production of C2H6 and H2, while under an argon environment, copper oxides organized into distinct nanoparticles favored the production of C2H4, with selectivity as high as 85% compared to 1% with pure TiO2.
Article
Chemistry, Physical
Min Huang, Shuyi Zhang, Bo Wu, Yao Wei, Xing Yu, Yongping Gan, Tiejun Lin, Fei Yu, Fanfei Sun, Zheng Jiang, Liangshu Zhong
Summary: In this study, a novel Cu and W codoped TiO2 photocatalyst was fabricated to achieve selective photooxidation of methane into oxygenates at ambient temperature, with limited formation of CO2. The Cu-W-TiO2 photocatalyst exhibited high productivity and selectivity, and its improved performance was attributed to the modulation of electronic and band structure, which facilitated methane activation and hindered overoxidation of oxygenates.
Article
Chemistry, Multidisciplinary
Tao Liu, Aori Qileng, Nuermaimaitijiang Wubulikasimu, Zhixiong Liu, Weipeng Liu, Yingju Liu
Summary: In this study, Fe-N co-doped TiO2 heterojunction photocatalysts were successfully synthesized, which exhibited multiple rutile/anatase TiO2 heterojunction structure, low bandgap, and significant absorption in visible light. The doped N from the TiO2-based metal organic framework (MOF) provided Ti-O-Fe tetrahedra and more oxygen vacancies, improving the photocatalytic efficiency of CO2 reduction to CH4.
Article
Chemistry, Physical
Xibo Zhang, Yaqin Wang, Kuan Chang, Shuangli Yang, Huijie Liu, Qian Chen, Zhaoxiong Xie, Qin Kuang
Summary: In this study, a unique hollow porous nanocage structure was prepared for Pd/ H-TiO2 catalysts to selectively convert methane into methanol under mild conditions with the reaction of O2. The obtained Pd/H-TiO2 exhibited a high methanol production rate of 4.5 mmol/g/h with a selectivity of up to 70% under optimized conditions, surpassing most reported values. The mechanism study revealed the significant role of ˙OH radicals produced by photogenerated holes in the activation of methane into ˙CH3 species, which were further oxidized into methanol by ˙O2 radicals formed by photogenerated electrons. The strong metal-support interaction and unique porous hollow structure effectively enhanced the catalytic activity. These findings provide guidance for the design of high-performance photocatalysts for the selective photocatalytic oxidation of methane.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Chemistry, Multidisciplinary
Min Huang, Shuyi Zhang, Bo Wu, Xing Yu, Yongping Gan, Tiejun Lin, Fei Yu, Yuhan Sun, Liangshu Zhong
Summary: A tunable band structure W-doped TiO2 photocatalyst was designed for the photocatalytic oxidation of methane to C-1 oxygenates using O-2 at low temperature. The W-doping improved the photocatalytic performance, achieving a liquid oxygenates productivity of 12.2 mmol g(-1) and a selectivity of 99.4%. Additionally, the selectivity of COx was effectively decreased from 21.2% to 0.6%. W-doping not only enhanced light absorption but also promoted the separation of photo-generated carriers, improving methane conversion.
Article
Energy & Fuels
Liyan Ming, Chunling Wang, Yun Hang Hu
Summary: This study presents a rare earth POM-based photocatalyst CePMo/TiO2 for efficient conversion of methane into organic oxygenates. CePMo/TiO2 exhibits excellent catalytic performance under 1.5G sunlight irradiation and the addition of CePMo enhances the photocatalytic activity of TiO2 for organic oxygenates.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2021)
Article
Chemistry, Applied
Antonietta Mancuso, Olga Sacco, Vincenzo Vaiano, Diana Sannino, Stefania Pragliola, Vincenzo Venditto, Nicola Morante
Summary: Fe-Pr co-doped TiO2 photocatalysts exhibit higher photocatalytic efficiency in the degradation of Acid Orange 7 azo dye and phenol, attributed to the co-doping of TiO2 with Pr and Fe ions leading to a reduction of the band gap value and enhanced generation of oxygen vacancies. The optimized Fe-Pr co-doped TiO2 shows the best performance in terms of treatment time under LED visible light irradiation.
Article
Chemistry, Multidisciplinary
Pu Wang, Run Shi, Yunxuan Zhao, Zhenhua Li, Jiaqing Zhao, Jiaqi Zhao, Geoffrey I. N. Waterhouse, Li-Zhu Wu, Tierui Zhang
Summary: In this study, the photocatalytic oxidative coupling of methane (OCM) over transition-metal-loaded ZnO photocatalysts was systematically investigated. A 1 wt% Au/ZnO catalyst exhibited remarkable C-2-C-4 hydrocarbon production rate and selectivity under light irradiation. The selectivity towards C-C coupling products strongly depends on the metal type and its interaction with ZnO. The findings suggest that the d-sigma center can be a suitable descriptor for predicting product selectivity during OCM over metal/ZnO photocatalysts.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Environmental Sciences
Jie Li, Yuxiang Yang, Zhiyong Han, Yan Huang, Hongming Yuan, Chaoying Ni
Summary: In this paper, Fe-Ce bimetallic-doped composites were synthesized using SiO2 aerogel as a carrier for the adsorption and degradation of trinitrogen from industrial or domestic wastewater. The photocatalytic efficiency was found to be the best when the catalyst dosage was 0.01 g, pH value was 11.0, and the concentration of H2O2 was 80 mmol/L, with the degradation efficiency of trinitrogen remaining above 70%.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Engineering, Environmental
Emad N. Al-Shafei, D. Robert Brown, Sai P. Katikaneni, Hassan Aljama, Hameed H. Al-Badairy
Summary: This study investigated the direct conversion of CO2 with methane using a selective catalyst, with ZrO2/TiO2 based catalyst showing promising results. Different techniques were used to characterize the catalyst and it was found that a Langmuir-Hinshelwood mechanism best explained the reaction mechanism. The presence of carbon dioxide resulted in the production of more acetic acid, indicating a more favorable process compared to the dimerization reaction.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Applied
Kexin Zou, Akira Yamamoto, Hisao Yoshida
Summary: In this study, the photocatalytic functionalization of aromatic rings was investigated using metal-loaded titanium oxide photocatalyst. The direct methylation of benzene was achieved by using acetic acid as a methylation reagent under light irradiation.
Article
Chemistry, Organic
Daiki Kuwana, Yuma Komori, Masanori Nagatomo, Masayuki Inoue
Summary: A new reaction system utilizing heterogeneous semiconductor photoredox catalysis was developed for decarboxylative radical coupling reactions, leading to the formation of C(sp(3))-C(sp(3)) bonds. The study showed that this method enables simple and mild transformations for the one-step assembly of oxygenated linear and branched carbon chains.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Environmental Sciences
Li-qiang Qi, Zhe Yu, Qi-hao Chen, Jing-xin Li, Hao-bo Xue, Feng Liu
Summary: This paper proposed a hybrid system that combined dielectric barrier discharge plasma with catalysis for toluene degradation. Photocatalysts TiO2 doped with Mn and Fe were used to improve the performance of the system. The effects of doping ratio, electric field intensity, AC frequency, gas flow rate, and initial concentration on toluene degradation efficiency, ozone decomposition capacity, and COx selectivity were investigated. The best doping ratios were found to be 1.0% for both Mn and Fe, and increasing electric field intensity significantly improved the synergism of the system.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Biochemistry & Molecular Biology
Iwona Pelech, Piotr Staciwa, Daniel Sibera, Ewelina Kusiak-Nejman, Antoni W. Morawski, Joanna Kapica-Kozar, Urszula Narkiewicz
Summary: In this study, ZnO/carbon spheres composites were prepared using zinc chloride and potassium oxalate as activating agents. The effects of their addition and preparation conditions on carbon dioxide adsorption properties were investigated. It was found that the sorption capacity measured at 40 degrees C confirmed the trend measured at 0 and 25 degrees C. The sample activated using potassium oxalate and modified using zinc chloride exhibited stable performance and high CO2 adsorption capacity during the consecutive multicycle adsorption-desorption process.
Article
Biochemistry & Molecular Biology
Agnieszka Sienkiewicz, Paulina Rokicka-Konieczna, Agnieszka Wanag, Ewelina Kusiak-Nejman, Antoni W. Morawski
Summary: This study presents the visible-light photocatalytic performance of 3-aminopropyltriethoxysilane (APTES)-modified TiO2 nanomaterials obtained by solvothermal modification and calcination. The APTES/TiO2 photocatalysts exhibit higher pore volume and specific surface area, and the adsorption process negatively affects the photocatalytic properties. The highest dye decomposition degree is observed for nanomaterials calcined at 900 degrees C with optimal APTES concentration of 500 mM.
Article
Chemistry, Physical
Antoni Waldemar Morawski, Katarzyna Cmielewska, Kordian Witkowski, Ewelina Kusiak-Nejman, Iwona Pelech, Piotr Staciwa, Ewa Ekiert, Daniel Sibera, Agnieszka Wanag, Marcin Gano, Urszula Narkiewicz
Summary: A new photocatalyst for CO2 reduction has been developed, which shows high CO2 adsorption capacity and selectivity towards CO. The use of this photocatalyst eliminates the need for separating CO from the gas mixture after the reaction.
Article
Biochemistry & Molecular Biology
Paulina Rokicka-Konieczna, Agata Markowska-Szczupak, Ewelina Kusiak-Nejman, Antoni W. Morawski
Summary: This study presents the characteristics of saccharose-modified TiO2 photocatalysts obtained through a low-temperature hydrothermal method. The influence of these photocatalysts on the survivability and enzyme activity of Escherichia coli and Staphylococcus epidermidis under UV-A and artificial solar light was examined. The TiO2-1%-S-100 photocatalysts were capable of achieving complete inactivation of the bacteria under artificial solar light irradiation in less than 1 hour. The study also discusses the impacts of sugars on the photocatalytic activity and disinfection performance.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Chemistry, Physical
Nikos Guskos, Grzegorz Zolnierkiewicz, Ewelina Kusiak-Nejman, Aleksander Guskos, Konstantinos Aidinis, Marta Bobrowska, Pawel Berczynski, Agnieszka Wanag, Iwona Pelech, Urszula Narkiewicz, Antoni W. Morawski
Summary: Nanocomposites based on nanocrystalline titania modified with graphene-related materials showed the presence of magnetic agglomerates. The magnetic resonance spectra parameters depended strongly on the materials' modification processes. Reduction of graphene oxide increased the number of magnetic moments and caused changes in reorientation and relaxation processes. At room temperature, wide resonance lines dominated in all studied nanocomposites, with narrow resonance lines derived from conduction electrons in some cases. Some nanocomposites exhibited single domain magnetic (ferromagnetic) arrangement, while others showed magnetic anisotropy. In addition, EPR spectra of free radicals were observed for all samples at 4K. Magnetic resonance imaging methods can capture even small number of localized magnetic moments, significantly affecting the physicochemical properties of the materials.
Article
Chemistry, Multidisciplinary
Antoni W. Morawski, Ewelina Kusiak-Nejman, Iwona Pelech, Katarzyna Cmielewska, Daniel Sibera, Piotr Staciwa, Agnieszka Wanag, Marcin Gano, Ewa Ekiert, Joanna Kapica-Kozar, Kordian Witkowski, Urszula Narkiewicz
Summary: This paper describes a new approach for hydrogen production from water using carbon dioxide-mediated water decomposition under UV radiation. By saturating the water solution with dissolved sodium hydroxide and gaseous carbon dioxide, the formed bicarbonate and carbonate ions prevent the recombination of hydroxyl and hydrogen radicals, leading to the prioritized formation of hydrogen gas. In the best system, the hydrogen production reached 0.6 μmol/h during 24 hours of UV-C radiation.
Article
Biotechnology & Applied Microbiology
Sylwia Mozia, Revathy Rajakumaran, Kacper Szymanski, Marek Gryta
Summary: The study focuses on the treatment of contaminated water using a hybrid system combining advanced oxidation processes and membrane technology. The results showed that increasing the feed temperature improved the permeate flux and degradation efficiency, while aeration of the feed enhanced product quality. The system exhibited good stability and produced high-quality permeate during long-term operation.
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
(2023)
Article
Chemistry, Physical
Aleksandra Babyszko, Agnieszka Wanag, Ewelina Kusiak-Nejman, Antoni Waldemar Morawski
Summary: This paper investigates the effects of fumed silica modification and calcination temperature on the physicochemical properties and activity of photocatalysts under UV-VIS and VIS light. The materials were synthesized using titanium tetraisopropoxide hydrolysis and subsequent calcination. Various analytical techniques were used to characterize the nanomaterials. It was found that SiO2 modification inhibited phase transformation and crystal growth during calcination. The photocatalytic activity was enhanced by SiO2 addition and calcination, with the highest activity observed for the SiO2(11.1%)/TiO2_600 photocatalyst.
Article
Chemistry, Physical
Ewelina Kusiak-Nejman, Katarzyna Cmielewska, Agnieszka Wanag, Ewa Ekiert, Iwona Pelech, Urszula Narkiewicz, Antoni W. Morawski
Summary: Industrial TiO2 suspension from sulphate technology was used for samples preparation. One sample was directly calcined in an argon stream at 800 C-o. The second one, before the calcination in the same conditions, was modified with APTES in such a way that the final product contained about 2 wt% of silicon. Photocatalysts were tested in the CO2 reduction reaction containing the addition of gaseous nitrogen and water vapour. No activity was observed in the CO2 reduction reaction for a directly calcined sample that mainly consists of a rutile phase. It was found that the addition of silicon prevents the anatase-to-rutile phase transition by forming a Si-O-Ti chain containing the anatase phase and leads to gaseous products: hydrogen, carbon monoxide and methane, and ammonia. The presence of silicon generates paramagnetic recentres with g= 2.0028, which are associated with oxygen vacancies and delocalized electrons. This electronic structure is critical to the photocatalytic reduction of CO2 because the pure rutile phase (without silicon modification) does not reduce CO2, but only the presence of ammonia was found in the products.
APPLIED CATALYSIS A-GENERAL
(2023)
Article
Biochemistry & Molecular Biology
Magdalena Chareza, Katarzyna Przygrodzka, Anna Zywicka, Bartlomiej Grygorcewicz, Peter Sobolewski, Sylwia Mozia, Marcin Smiglak, Radoslaw Drozd
Summary: Bacterial biofilms are a major problem in the wound healing process due to antibiotic resistance mechanisms. This study investigated the therapeutic properties of alginate lyase (AlgL) immobilised on BC membranes for protecting wounds from Pseudomonas aeruginosa infection. The AlgL immobilisation significantly reduced the amount of polysaccharides in the biofilm and showed synergism with gentamicin in killing bacterial cells.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Biochemistry & Molecular Biology
Paulina Rokicka-Konieczna, Agnieszka Wanag, Agnieszka Sienkiewicz, Dylan Shun Izuma, Ewa Ekiert, Ewelina Kusiak-Nejman, Chiaki Terashima, Atsuo Yasumori, Akira Fujishima, Antoni W. W. Morawski
Summary: The antibacterial activity of TiO2 photocatalysts modified by 3-aminopropyltriethoxysilane (APTES) was evaluated against Escherichia coli and Staphylococcus epidermidis under artificial solar light (ASL) irradiation. APTES-functionalized TiO2 samples were prepared through a solvothermal process followed by calcination. The best antibacterial properties were observed in the TiO2-4 h-120 degrees C-300 mM-Ar-300 degrees C sample, which had a positive zeta potential, high surface area, and porous volume.
Article
Chemistry, Physical
Ewelina Kusiak-Nejman, Katarzyna Cmielewska, Iwona Pelech, Ewa Ekiert, Piotr Staciwa, Daniel Sibera, Agnieszka Wanag, Joanna Kapica-Kozar, Marcin Gano, Urszula Narkiewicz, Antoni W. Morawski
Summary: This study presents new photocatalysts obtained by treating carbon spheres and TiO2 in a microwave reactor at high pressure and temperature, and depositing them on glass fibre cloths. These photocatalysts showed high CO2-adsorption and photoactivity in simultaneous water-splitting process, generating H-2, reducing CO2 to CO and CH2, and reducing N-2 to NH3. The addition of carbon spheres maintained a high selectivity of nitrogen fixation.
Article
Chemistry, Physical
Antoni W. Morawski, Marcin Gano, Katarzyna Cmielewska, Ewelina Kusiak-Nejman, Iwona Pelech, Piotr Staciwa, Ewa Ekiert, Urszula Narkiewicz
Summary: In the face of increasing global carbon dioxide emissions and the urgent need to mitigate climate change, the development of efficient and sustainable strategies for CO2 conversion has gained significant attention. This paper uses ZnO as a photocatalyst to investigate its efficiency in the photoreduction of CO2 in a gas-phase system. The study found that the particle size of ZnO has a significant impact on the process efficiency, with the smallest particle size (18 nm) showing the most effective catalytic activity for CO2 photoreduction.
Article
Nanoscience & Nanotechnology
Agnieszka Sienkiewicz, Ewelina Kusiak-Nejman, Agnieszka Wanag, Konstantinos Aidinis, Danuta Piwowarska, Antoni W. Morawski, Niko Guskos
Summary: APTES-TiO2 samples prepared by high-temperature calcination showed high intensity of electron paramagnetic resonance (EPR) lines and photocatalytic activity.
REVIEWS ON ADVANCED MATERIALS SCIENCE
(2022)
Article
Engineering, Chemical
Agnieszka Sienkiewicz, Paulina Rokicka-Konieczna, Agnieszka Wanag, Ewelina Kusiak-Nejman, Antoni W. Morawski
Summary: In this study, the antibacterial and photocatalytic properties of APTES/TiO2 nanomaterials were investigated by adjusting the modifier concentration and modification temperature. The results showed that the optimal antibacterial properties and photocatalytic activity occurred at different concentrations of photocatalyst, while increasing the modifier concentration enhanced the photoactivity.
DESALINATION AND WATER TREATMENT
(2022)
Article
Chemistry, Applied
Qingyuan Zheng, Jack H. Williams, Scott Elgersma, Mick D. Mantle, Andrew J. Sederman, G. Leendert Bezemer, Constant M. Guedon, Lynn F. Gladden
Summary: In this study, a pilot-scale fixed-bed reactor compatible with NMR/MRI was developed for Fischer-Tropsch synthesis. Multiple magnetic resonance techniques were applied to quantitatively characterize different product species within catalyst pellets, providing valuable information for catalyst and reactor optimization.
Article
Chemistry, Applied
Lisa Ramisch, Sebastian Pfaff, Sabrina M. Gericke, Edvin Lundgren, Johan Zetterberg
Summary: We present a combination of optical operando techniques that allow simultaneous measurement of adsorbed species on catalyst surfaces, monitoring of surface oxide formation, and imaging of the gas phase above the catalyst surface. The experimental setup was validated by studying CO oxidation on Pd(100) at different pressures, revealing the effects of pressure on the heterogeneous catalytic reaction.
Article
Chemistry, Applied
Marta Paniagua, Gabriel Morales, Juan A. Melero, Daniel Garcia-Salgado
Summary: The influence of common impurities in levulinic acid on the catalytic performance of different acid catalysts for bio-jet fuel production was studied. It was found that furfural had the greatest detrimental effect on catalyst performance, while propyl-sulfonic acid-modified SBA-15 and sulfonic acid resin Amberlyst-70 showed good regeneration ability.
Article
Chemistry, Applied
Jesus Tapiador, Pedro Leo, Guillermo Calleja, Gisela Orcajo
Summary: This study presents a new MOF material, Zn-URJC-13, with acid and basic sites, permanent porosity, and high affinity to CO2 molecules. The Zn-URJC-13 catalyst exhibits efficient performance in CO2 cycloaddition reactions and can be reused multiple times.
Article
Chemistry, Applied
Dan Zhao, Vita A. Kondratenko, Dmitry E. Doronkin, Shanlei Han, Jan-Dierk Grunwaldt, Uwe Rodemerck, David Linke, Evgenii V. Kondratenko
Summary: This study demonstrates the potential of cheap and commercially available Zr or Ti-based supports and ZnO to serve as active and selective catalysts for propane dehydrogenation (PDH). The catalytically active species formed in situ under PDH conditions consist of isolated ZnOx. ZnOx on the surface of LaZrOx shows the highest rate of propene formation.
Article
Chemistry, Applied
Hanbyeol Kim, Jung Rae Kim, Young-Kwon Park, Jeong-Myeong Ha, Jungho Jae
Summary: In this study, metal phosphates were used as catalysts for biomass conversion to produce sustainable aromatics through DielsAlder cycloaddition reactions. The effects of synthesis method, activation method, and P/Ti molar ratio on the structure and acid properties of titanium phosphate catalysts were systematically studied. The mesoporous titanium phosphate catalyst synthesized by hydrothermal method at 180℃ for 12 h followed by ethanol refluxing at 60℃ for 24 h at a molar P/Ti ratio of 1 showed the highest surface area and acid site density.
Article
Chemistry, Applied
Yasin Khani, Sumin Pyo, Kwang-Eun Jeong, Chul-Ung Kim, Moonis Ali Khan, Byong-Hun Jeon, Kun-Yi Andrew Lin, Siyoung Q. Choi, Young-Kwon Park
Summary: A protonated form of Zeolite Socony Mobil-5 (H-ZSM-5) catalyst was synthesized through a hydrothermal method using different sources of silica. The effect of loading the catalyst with yttrium, samarium, and gadolinium on the acidic properties was investigated. Among the metal-loaded catalysts, the Sm/LHZ catalyst showed the best performance in the methanol to propylene conversion due to its high amount of weak and intermediate acid sites, while the Gd-LHZ catalyst increased the selectivity towards ethane and propane.
Article
Chemistry, Applied
Michael Franc, Ivana Cisarova, Jan Vesely
Summary: The present study investigates an enantioselective cyclization of enals with imidazolone derivatives catalyzed by a combination of achiral Pd(0) complex and chiral secondary amine. Corresponding spirocyclic imidazolones were produced in high yields with moderate diastereoselectivity and excellent enantioselectivity. The developed co-operative catalytic methodology provides a highly substituted spirocyclic scaffold with four stereogenic centers under mild conditions.
Article
Chemistry, Applied
Mauro Alvarez, Jennifer Cueto, David P. Serrano, Pablo Marin, Salvador Ordonez
Summary: This study focuses on improving the formulation and preparation methods of catalysts for the production of dimethyl carbonate. By using suitable catalyst preparation methods and copper salt precursors, the researchers successfully produced catalysts with optimal performance for dimethyl carbonate formation.
Article
Chemistry, Applied
Claudia J. Keijzer, Luc C. J. Smulders, Dennie Wezendonk, Jan Willem de Rijk, Petra E. de Jongh
Summary: This study investigates the catalytic behavior of alpha-alumina supported silver catalysts in the presence of chloride. It is found that the particle size of silver can affect the selectivity of the catalyst, but different strategies lead to different results. In this size range, the selectivity of ethylene oxide is correlated to the Ag : Al2O3 surface ratio.
Article
Chemistry, Applied
Takeshi Aihara, Wataru Aoki, Michikazu Hara, Keigo Kamata
Summary: The development of acid-base bifunctional catalysts is important for promoting specific chemical transformations. In this study, Ti-based perovskite oxides were synthesized and used as catalysts for two C-C bond-forming reactions (cyanosilylation and Knoevenagel condensation). The highly pure SrTiO3 nanoparticles with a high specific surface area exhibited the highest catalytic performance, and could be easily recovered and reused.
Article
Chemistry, Applied
Olga Gorlova, Petra Pribylova, Eliska Vyskocilova, Katerina Peroutkova, Jan Kohout, Iva Paterova
Summary: This study investigates the Baeyer-Villiger oxidation of beta-cyclocitral using tin-modified mixed oxides as catalysts. The optimal reaction conditions and the effects of various factors on the reaction course and selectivity were determined. The results show that tin-modified mixed oxides exhibit high activity and selectivity in the oxidation reaction.
Article
Chemistry, Applied
M. I. Avila, M. M. Alonso-Doncel, L. Briones, G. Gomez-Pozuelo, J. M. Escola, D. P. Serrano, A. Peral, J. A. Botas
Summary: The catalytic fast pyrolysis of lignin using ion-exchanged zeolite catalysts showed significant improvements in bio-oil quality and the production of aromatic hydrocarbons and oxygenated compounds.
Article
Chemistry, Applied
Enrico Catizzone, Giorgia Ferrarelli, Paolo Bruno, Girolamo Giordano, Massimo Migliori
Summary: The acid-catalysed alcohol conversion reaction is a promising route for de-fossilization strategies. Research on pure alcohol conversion and simultaneous dehydration of mixed alcohols have shown different product compositions, with the type and distribution of acid sites affecting the reaction mechanism.
Article
Chemistry, Applied
Alireza Ranjbari, Juho Kim, Jihee Yu, Jiyun Kim, Mireu Park, Nayoung Kim, Kristof Demeestere, Philippe M. Heynderickx
Summary: This study investigated a novel kinetic model for the adsorption and photocatalytic degradation of methyl orange using commercial ZnO and reduced ZnO photocatalysts. The results provided new insights into the interaction of catalysts with molecules of different charges and compared with a previous study on methylene blue. The presence of oxygen vacancies in ZnO and their effects on adsorption and photocatalytic degradation were analyzed, and the photocatalytic degradation rate of reduced ZnO was found to increase significantly.
