Understanding how substrate structure alters an enzyme's conformational landscape is central to catalyst design. Using single-molecule electronic sensors, we reveal how substitutions on an HDAC8 substrate modulate the enzyme's underlying catalytic dynamics. We demonstrate that a trifluoroacetyl group accelerates catalysis, while a Boc cap and an allosteric activator synergistically simplify the kinetic pathway by stabilizing productive conformations. These findings provide direct, real-time insight into how substrate-induced conformational dynamics control enzyme catalysis.
{"title":"Substrate structure modulates the catalytic dynamics of HDAC8 at the single-molecule level","authors":"Seungyong You, Sakurako Tani, Sanku Mallik, Zhongyu Yang, Mohiuddin Quadir and Yongki Choi","doi":"10.1039/D5CY00729A","DOIUrl":"https://doi.org/10.1039/D5CY00729A","url":null,"abstract":"<p >Understanding how substrate structure alters an enzyme's conformational landscape is central to catalyst design. Using single-molecule electronic sensors, we reveal how substitutions on an HDAC8 substrate modulate the enzyme's underlying catalytic dynamics. We demonstrate that a trifluoroacetyl group accelerates catalysis, while a Boc cap and an allosteric activator synergistically simplify the kinetic pathway by stabilizing productive conformations. These findings provide direct, real-time insight into how substrate-induced conformational dynamics control enzyme catalysis.</p>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":" 24","pages":" 7324-7328"},"PeriodicalIF":4.2,"publicationDate":"2025-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/cy/d5cy00729a?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145705935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhiyuan Zhang, Lili Yu, Yan Li, Zhilong Zhang, Haotong Chen, Zilong Han and Li Li
Adipic acid plays a crucial role as a key constituent of polymers. The electrocatalytic strategy of KA oil (cyclohexanol and cyclohexanone) electrooxidation has been recognized as an effective way to produce adipic acid compared to the commercial thermocatalytic oxidation method using corrosive nitric acid and producing nitrous oxide. Herein, we report a ligand covalent modification strategy to enhance the current density of KA oil electrooxidation by NiMn-LDH modified with dodecyl triethoxysilane (NiMn-LDH-DTES) via a silanization reaction. For example, NiMn-LDH-DTES exhibits 1.7-fold current density for cyclohexanol electrooxidation compared to pure NiMn-LDH. The cyclohexanol conversion rate and H2 production rate reach 0.044 mmol cm−2 h−1 and 43.2 mL cm−2 h−1 at 1.52 V vs. RHE, which are 1.7- and 1.5-fold higher than those of NiMn-LDH, respectively. And at high cyclohexanol conversion of 96.2%, the yield of adipic acid reaches 79.4% with FE of 83.4% and selectivity of 94.4%. NiMn-LDH-DTES demonstrated its efficiency for cyclohexanone oxidation with enhanced performance. We confirmed that the modification of NiMn-LDH by DTES can promote the generation and exposure of more reactive sites, and also facilitates the adsorption of KA oil, thus enabling the high reaction rate.
{"title":"Covalent modified LDH electrocatalyst for enhanced electrocatalytic oxidation of KA oil to adipic acid","authors":"Zhiyuan Zhang, Lili Yu, Yan Li, Zhilong Zhang, Haotong Chen, Zilong Han and Li Li","doi":"10.1039/D5CY00804B","DOIUrl":"https://doi.org/10.1039/D5CY00804B","url":null,"abstract":"<p >Adipic acid plays a crucial role as a key constituent of polymers. The electrocatalytic strategy of KA oil (cyclohexanol and cyclohexanone) electrooxidation has been recognized as an effective way to produce adipic acid compared to the commercial thermocatalytic oxidation method using corrosive nitric acid and producing nitrous oxide. Herein, we report a ligand covalent modification strategy to enhance the current density of KA oil electrooxidation by NiMn-LDH modified with dodecyl triethoxysilane (NiMn-LDH-DTES) <em>via</em> a silanization reaction. For example, NiMn-LDH-DTES exhibits 1.7-fold current density for cyclohexanol electrooxidation compared to pure NiMn-LDH. The cyclohexanol conversion rate and H<small><sub>2</sub></small> production rate reach 0.044 mmol cm<small><sup>−2</sup></small> h<small><sup>−1</sup></small> and 43.2 mL cm<small><sup>−2</sup></small> h<small><sup>−1</sup></small> at 1.52 V <em>vs.</em> RHE, which are 1.7- and 1.5-fold higher than those of NiMn-LDH, respectively. And at high cyclohexanol conversion of 96.2%, the yield of adipic acid reaches 79.4% with FE of 83.4% and selectivity of 94.4%. NiMn-LDH-DTES demonstrated its efficiency for cyclohexanone oxidation with enhanced performance. We confirmed that the modification of NiMn-LDH by DTES can promote the generation and exposure of more reactive sites, and also facilitates the adsorption of KA oil, thus enabling the high reaction rate.</p>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":" 24","pages":" 7496-7503"},"PeriodicalIF":4.2,"publicationDate":"2025-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145705951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Patricia Petriskova, Peng Cheng, Tomas Roch, Hélène Métivier, Gilles Mailhot, Marcello Brigante and Olivier Monfort
In this work, activation oxidants like H2O2 and peroxydisulfate (S2O82−) were investigated in the presence of a recycled magnetite (rMG) obtained from Hymag'in company (France) both in the dark and under UVA light. The rMG is a micro-powder (0.5–1 μm particle size) predominantly composed of magnetite, but it also contains cubic γ-Fe2O3. Picloram (PIC) was employed as a model pollutant to investigate the performance of rMG. The effects of oxidants (type and concentration), light and water matrix were assessed. Better efficiencies were observed in systems containing peroxydisulfate (PDS) due to the better stability of sulfate radicals compared to hydroxyl radicals. In addition, iron leaching was observed in PDS-based systems, thus suggesting that homogeneous Fenton reactions increased the catalytic efficiency. The effect of light boosted the efficiency due to regeneration of Fe(II) by Fe(III) photolysis. The 0.2 g L−1 rMG can completely degrade PIC under UVA light in the presence of PDS after only 2 h of reaction. In wastewater effluents, rMG exhibited promising results with the removal of about 60% of PIC after 4 h, and rMG was significantly better than commercial magnetite. The present work highlights the feasibility of using wastes from the iron industry to treat wastewater, which is an added value for the circular economy of water.
在这项工作中，在法国Hymag'in公司的回收磁铁矿（rMG）的存在下，在黑暗和UVA光下研究了活化氧化剂H2O2和过硫酸氢盐（S2O82−）。rMG是一种以磁铁矿为主的微粉（粒径0.5 ~ 1 μm），同时含有立方γ-Fe2O3。以Picloram （PIC）为模型污染物，研究了rMG的性能。评估了氧化剂（种类和浓度）、光照和水基质对其的影响。由于与羟基自由基相比，硫酸盐自由基的稳定性更好，因此在含有过硫酸氢盐（PDS）的系统中观察到更好的效率。此外，在基于pds的体系中观察到铁浸出，这表明均相Fenton反应提高了催化效率。光的作用提高了铁（III）光解再生的效率。0.2 g L−1 rMG在UVA光下，在PDS存在下，仅反应2h即可完全降解PIC。在废水中，rMG表现出良好的效果，在4 h后，PIC的去除率约为60%，并且rMG明显优于商业磁铁矿。本研究强调了利用炼铁废水处理废水的可行性，这是水循环经济的一个附加价值。
{"title":"Recycled magnetite as a sustainable photo-catalyst for hydrogen peroxide and peroxydisulfate activation: insights into the efficiency and mechanism of picloram removal in water","authors":"Patricia Petriskova, Peng Cheng, Tomas Roch, Hélène Métivier, Gilles Mailhot, Marcello Brigante and Olivier Monfort","doi":"10.1039/D5CY00954E","DOIUrl":"https://doi.org/10.1039/D5CY00954E","url":null,"abstract":"<p >In this work, activation oxidants like H<small><sub>2</sub></small>O<small><sub>2</sub></small> and peroxydisulfate (S<small><sub>2</sub></small>O<small><sub>8</sub></small><small><sup>2−</sup></small>) were investigated in the presence of a recycled magnetite (rMG) obtained from <em>Hymag'in</em> company (France) both in the dark and under UVA light. The rMG is a micro-powder (0.5–1 μm particle size) predominantly composed of magnetite, but it also contains cubic γ-Fe<small><sub>2</sub></small>O<small><sub>3</sub></small>. Picloram (PIC) was employed as a model pollutant to investigate the performance of rMG. The effects of oxidants (type and concentration), light and water matrix were assessed. Better efficiencies were observed in systems containing peroxydisulfate (PDS) due to the better stability of sulfate radicals compared to hydroxyl radicals. In addition, iron leaching was observed in PDS-based systems, thus suggesting that homogeneous Fenton reactions increased the catalytic efficiency. The effect of light boosted the efficiency due to regeneration of Fe(<small>II</small>) by Fe(<small>III</small>) photolysis. The 0.2 g L<small><sup>−1</sup></small> rMG can completely degrade PIC under UVA light in the presence of PDS after only 2 h of reaction. In wastewater effluents, rMG exhibited promising results with the removal of about 60% of PIC after 4 h, and rMG was significantly better than commercial magnetite. The present work highlights the feasibility of using wastes from the iron industry to treat wastewater, which is an added value for the circular economy of water.</p>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":" 24","pages":" 7516-7524"},"PeriodicalIF":4.2,"publicationDate":"2025-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145705953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Victor Rosa , Fabio Cameli , Yves Schuurman , Kevin M. Van Geem , Georgios D. Stefanidis
The advancement of electrified chemical processes prompts interest in novel technologies such as plasma-based methane (CH4) conversion into high-demand chemicals. Specifically, nanosecond-pulsed discharges (NPDs) coupled with downstream Pd-based catalysts have demonstrated the best performance in a two-step, integrated process for converting CH4 into ethylene (C2H4). Given the untested composition range involved in this application, the focus of this work is the isolated performance of Pd-based catalysts in typical post-plasma conditions. Extensive campaigns of experiments are run in both traditional and novel stream compositions. The differences with traditional tail-end olefin-rich hydrogenation are highlighted, and a hybrid steady-state kinetic model is proposed, combining the traditional Langmuir–Hinshelwood–Hougen–Watson (LHHW) approach with an improved reversible adsorption methodology. The ability to accurately predict C2H2 hydrogenation kinetics with C2H2-rich and C2H4-poor streams is achieved by the new model, contrary to existing conventional models. Preliminary insights into catalyst optimization for scalable plasma-to-olefin routes are presented.
{"title":"A kinetic model for Pd-based hydrogenation of acetylene-rich streams typical of post-plasma applications","authors":"Victor Rosa , Fabio Cameli , Yves Schuurman , Kevin M. Van Geem , Georgios D. Stefanidis","doi":"10.1039/d5cy00529a","DOIUrl":"10.1039/d5cy00529a","url":null,"abstract":"<div><div>The advancement of electrified chemical processes prompts interest in novel technologies such as plasma-based methane (CH<sub>4</sub>) conversion into high-demand chemicals. Specifically, nanosecond-pulsed discharges (NPDs) coupled with downstream Pd-based catalysts have demonstrated the best performance in a two-step, integrated process for converting CH<sub>4</sub> into ethylene (C<sub>2</sub>H<sub>4</sub>). Given the untested composition range involved in this application, the focus of this work is the isolated performance of Pd-based catalysts in typical post-plasma conditions. Extensive campaigns of experiments are run in both traditional and novel stream compositions. The differences with traditional tail-end olefin-rich hydrogenation are highlighted, and a hybrid steady-state kinetic model is proposed, combining the traditional Langmuir–Hinshelwood–Hougen–Watson (LHHW) approach with an improved reversible adsorption methodology. The ability to accurately predict C<sub>2</sub>H<sub>2</sub> hydrogenation kinetics with C<sub>2</sub>H<sub>2</sub>-rich and C<sub>2</sub>H<sub>4</sub>-poor streams is achieved by the new model, contrary to existing conventional models. Preliminary insights into catalyst optimization for scalable plasma-to-olefin routes are presented.</div></div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":"15 23","pages":"Pages 7014-7029"},"PeriodicalIF":4.2,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145084519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Boshra Atwi , Dongren Wang , Johanna R. Bruckner , Wolfgang Frey , Michael R. Buchmeiser
The N- and O-chelating N-heterocyclic carbene (NHC) based Rh(i) and Rh(iii) complexes [RhCl(1-(quino-8-yl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(COD)] (, COD = 1,5-cyclooctadiene), [RhCl(1-(mesitylaminocarbonylmethyl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(COD)] (), [Rh(1-(mesitylaminocarbonylmethyl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(COD)+] [BF4−] (), [Rh(1-(mesitylamidocarbonylmethyl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(COD)] (), RhCl(1-(quino-8-yl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(Cp*)+] Cl− (, Cp* = pentamethylcyclopentadienyl), [RhCl(1-(quino-8-yl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(Cp*)+] [BF4−] (), [RhCl2(1-(mesitylaminocarbonylmethyl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(Cp*)] (), and [RhCl(1-(mesitylaminocarbonylmethyl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(Cp*)] [BF4−] () were prepared. The solid-state structures of , and are presented. Selected complexes were used in the hydroboration of terminal aliphatic alkynes under homogeneous conditions using HBpin (pin = pinacolate) as hydroboration reagent. As expected, only very low β(Z)-selectivity (1–27%) was observed under homogeneous conditions; by contrast, , , , and immobilized inside (hexagonally) ordered mesoporous silica (OMS) with pore sizes of 6.0 and 3.5 nm, respectively, showed improved β(Z) selectivity up to 30%. Most important, reactions carried out with , and supported on OMS35Å and additionally confined in a thin (1 nm) layer of the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM+ BF4−) using “solid catalyst with ionic liquid layer” (SCILL) conditions allowed for a pronounced increase in Z-selectivity up to 67%. Overall, the β(Z)/β(E) isomeric ratio was successfully increased up to a factor of 22 when going from homogenous to SCILL conditions. A mechanistic picture is presented.
{"title":"Confinement-induced Z-selectivity in the rhodium N-heterocyclic carbene-catalyzed hydroboration of terminal alkynes","authors":"Boshra Atwi , Dongren Wang , Johanna R. Bruckner , Wolfgang Frey , Michael R. Buchmeiser","doi":"10.1039/d5cy00860c","DOIUrl":"10.1039/d5cy00860c","url":null,"abstract":"<div><div>The N- and O-chelating <em>N</em>-heterocyclic carbene (NHC) based Rh(<span>i</span>) and Rh(<span>iii</span>) complexes [RhCl(1-(quino-8-yl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(COD)] (, COD = 1,5-cyclooctadiene), [RhCl(1-(mesitylaminocarbonylmethyl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(COD)] (), [Rh(1-(mesitylaminocarbonylmethyl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(COD)<sup>+</sup>] [BF<sub>4</sub><sup>−</sup>] (), [Rh(1-(mesitylamidocarbonylmethyl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(COD)] (), RhCl(1-(quino-8-yl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(Cp*)<sup>+</sup>] Cl<sup>−</sup> (, Cp* = pentamethylcyclopentadienyl), [RhCl(1-(quino-8-yl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(Cp*)<sup>+</sup>] [BF<sub>4</sub><sup>−</sup>] (), [RhCl<sub>2</sub>(1-(mesitylaminocarbonylmethyl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(Cp*)] (), and [RhCl(1-(mesitylaminocarbonylmethyl)-3-(trimethoxysilylpropyl)imidazol-2-ylidene)(Cp*)] [BF<sub>4</sub><sup>−</sup>] () were prepared. The solid-state structures of , and are presented. Selected complexes were used in the hydroboration of terminal aliphatic alkynes under homogeneous conditions using HBpin (pin = pinacolate) as hydroboration reagent. As expected, only very low <em>β</em>(<em>Z</em>)-selectivity (1–27%) was observed under homogeneous conditions; by contrast, , , , and immobilized inside (hexagonally) ordered mesoporous silica (OMS) with pore sizes of 6.0 and 3.5 nm, respectively, showed improved <em>β</em>(<em>Z</em>) selectivity up to 30%. Most important, reactions carried out with , and supported on OMS<sub>35Å</sub> and additionally confined in a thin (1 nm) layer of the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM<sup>+</sup> BF<sub>4</sub><sup>−</sup>) using “solid catalyst with ionic liquid layer” (SCILL) conditions allowed for a pronounced increase in <em>Z</em>-selectivity up to 67%. Overall, the <em>β</em>(<em>Z</em>)/<em>β</em>(<em>E</em>) isomeric ratio was successfully increased up to a factor of 22 when going from homogenous to SCILL conditions. A mechanistic picture is presented.</div></div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":"15 23","pages":"Pages 7059-7066"},"PeriodicalIF":4.2,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145584700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yifan Zhang , Jiaying Liu , Shiwei Wang , Zhihao Yu , Haojian Zhang , Dong Wang , Lin Zhu , Chunzheng Wu , Hongbo Yu
Modifying noble metal catalysts with transition metal oxides (MOx) can markedly enhance catalytic performance through synergistic effects, yet precise spatial colocalization of active metal and promoter phases remains challenging. Here, we report the synthesis of KIT-6 supported Pd–MOx (M = Fe, Co, Ni) hybrid nanostructures via in situ transformation of bimetallic PdM nanoparticles under controlled thermal conditions. The resulting Pd–MOx/KIT-6 catalysts displayed superior activity and selectivity in the selective hydrogenation of acetophenone to 1-phenylethanol compared with monometallic Pd/KIT-6. Among them, Pd–CoOx/KIT-6 (Pd/Co = 1 : 1) achieved the highest performance, with 99.7% acetophenone conversion and 98.2% selectivity, and demonstrated broad applicability for hydrogenating diverse ketones. Structural and kinetic studies revealed that interfacial Pd–CoOx sites play a pivotal role: Pd domains efficiently dissociate H2, while CoOx species enhance acetophenone adsorption. This synergistic interface-driven mechanism provides a general and cost-effective strategy for the selective hydrogenation of multifunctional substrates.
{"title":"Enhanced selective hydrogenation of acetophenone over KIT-6 supported Pd–MOx (M = Fe, Co, Ni) hybrid nanostructures","authors":"Yifan Zhang , Jiaying Liu , Shiwei Wang , Zhihao Yu , Haojian Zhang , Dong Wang , Lin Zhu , Chunzheng Wu , Hongbo Yu","doi":"10.1039/d5cy01108f","DOIUrl":"10.1039/d5cy01108f","url":null,"abstract":"<div><div>Modifying noble metal catalysts with transition metal oxides (MO<sub><em>x</em></sub>) can markedly enhance catalytic performance through synergistic effects, yet precise spatial colocalization of active metal and promoter phases remains challenging. Here, we report the synthesis of KIT-6 supported Pd–MO<sub><em>x</em></sub> (M = Fe, Co, Ni) hybrid nanostructures <em>via in situ</em> transformation of bimetallic PdM nanoparticles under controlled thermal conditions. The resulting Pd–MO<sub><em>x</em></sub>/KIT-6 catalysts displayed superior activity and selectivity in the selective hydrogenation of acetophenone to 1-phenylethanol compared with monometallic Pd/KIT-6. Among them, Pd–CoO<sub><em>x</em></sub>/KIT-6 (Pd/Co = 1 : 1) achieved the highest performance, with 99.7% acetophenone conversion and 98.2% selectivity, and demonstrated broad applicability for hydrogenating diverse ketones. Structural and kinetic studies revealed that interfacial Pd–CoO<sub><em>x</em></sub> sites play a pivotal role: Pd domains efficiently dissociate H<sub>2</sub>, while CoO<sub><em>x</em></sub> species enhance acetophenone adsorption. This synergistic interface-driven mechanism provides a general and cost-effective strategy for the selective hydrogenation of multifunctional substrates.</div></div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":"15 23","pages":"Pages 7244-7250"},"PeriodicalIF":4.2,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145584766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sazida Yasmin Sultana , Kabirun Ahmed , Jumana Ishrat , Pratyasha Borthakur , Hiya Talukdar , Nashreen S. Islam
In this study, an efficient and eco-friendly route for the selective synthesis of 5-hydroxymethyl-2-furancarboxylic acid (HMFCA), via oxidation of 5-hydroxymethylfurfural (HMF) with aqueous H2O2 using polymer-supported peroxidovanadium (pV) and peroxidotungsten (pW) compounds as catalysts, is described. The heterogeneous non-noble metal catalysts were prepared by immobilizing the peroxido derivatives of vanadium(v) and tungsten(vi) on polystyrene () resin functionalized with niacin () or asparagine (). The synthesized catalysts and were well characterized by elemental analysis, FTIR, Raman, NMR, XRD, XPS, SEM, EDX, BET and TGA analysis. The catalysts displayed excellent activity in facilitating quantitative conversion of HMF to provide the target product, HMFCA with >99% selectivity and a TON value of 50. Significant ‘green’ attributes of the catalytic protocol include the use of water as a solvent, aqueous H2O2 as a clean and safe oxidant and workable reaction temperature and time (60 °C, 1.3 h). Importantly, the catalysts are cost-effective, stable, and can be easily separated from the reaction mixture and recycled at least for five cycles without any significant reduction in activity or selectivity.
{"title":"Supported vanadium- and tungsten-based catalysts for selective and sustainable oxidation of 5-hydroxymethylfurfural to 5-hydroxymethyl-2-furancarboxylic acid with H2O2 in water","authors":"Sazida Yasmin Sultana , Kabirun Ahmed , Jumana Ishrat , Pratyasha Borthakur , Hiya Talukdar , Nashreen S. Islam","doi":"10.1039/d5cy00903k","DOIUrl":"10.1039/d5cy00903k","url":null,"abstract":"<div><div>In this study, an efficient and eco-friendly route for the selective synthesis of 5-hydroxymethyl-2-furancarboxylic acid (HMFCA), <em>via</em> oxidation of 5-hydroxymethylfurfural (HMF) with aqueous H<sub>2</sub>O<sub>2</sub> using polymer-supported peroxidovanadium (pV) and peroxidotungsten (pW) compounds as catalysts, is described. The heterogeneous non-noble metal catalysts were prepared by immobilizing the peroxido derivatives of vanadium(<span>v</span>) and tungsten(<span>vi</span>) on polystyrene () resin functionalized with niacin () or asparagine (). The synthesized catalysts and were well characterized by elemental analysis, FTIR, Raman, NMR, XRD, XPS, SEM, EDX, BET and TGA analysis. The catalysts displayed excellent activity in facilitating quantitative conversion of HMF to provide the target product, HMFCA with >99% selectivity and a TON value of 50. Significant ‘green’ attributes of the catalytic protocol include the use of water as a solvent, aqueous H<sub>2</sub>O<sub>2</sub> as a clean and safe oxidant and workable reaction temperature and time (60 °C, 1.3 h). Importantly, the catalysts are cost-effective, stable, and can be easily separated from the reaction mixture and recycled at least for five cycles without any significant reduction in activity or selectivity.</div></div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":"15 23","pages":"Pages 7209-7227"},"PeriodicalIF":4.2,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145584763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dongwei Yao , Jiadong Hu , Xiaohan Hu , Yuxi Li , Weiyang Jin , Feng Wu
Cu-SSZ-13, a diesel vehicle selective catalytic reduction (SCR) catalyst, faces deactivation problems caused by sulfur poisoning and hydrothermal aging, which coexist in diesel vehicle after-treatment systems, complicating its actual deactivation. Activity evaluation and characterization tests were used to investigate the coupled deactivation properties as well as sulfur poisoning and hydrothermal aging mechanisms of the Cu-SSZ-13 SCR catalyst. The activity evaluation tests included the standard SCR reaction and NH3 oxidation tests, and the characterization tests included the NH3-TPD test, SO2-TPD test, and NO + NH3 TPR test. The sulfur-poisoned active sites of Cu-SSZ-13 inhibited the migration of ZCuOH to Z2Cu in the subsequent hydrothermal aging, resulting in lower SCR activity at high temperatures than the samples hydrothermally aged only. The migration of ZCuOH to Z2Cu caused by hydrothermal aging increased the sulfur resistance of the active sites, decreased the sulfur species production, and increased the SCR activity at low temperatures. For the samples that hydrothermally aged with SO2 at 650 °C, some sulfur species were formed, which significantly affected the SCR activity in the whole temperature range. At 750 °C, the low-temperature SCR activity showed no reduction. At 850 °C, SO2 promoted the formation of copper oxide. These research conditions closely resemble real-world aging conditions, refining the mechanism of coupled deactivation due to hydrothermal aging and sulfur poisoning in the Cu-SSZ-13 catalyst.
{"title":"Experimental investigation on the coupling mechanism between sulfur poisoning and hydrothermal aging of the Cu-SSZ-13 SCR catalyst","authors":"Dongwei Yao , Jiadong Hu , Xiaohan Hu , Yuxi Li , Weiyang Jin , Feng Wu","doi":"10.1039/d5cy00758e","DOIUrl":"10.1039/d5cy00758e","url":null,"abstract":"<div><div>Cu-SSZ-13, a diesel vehicle selective catalytic reduction (SCR) catalyst, faces deactivation problems caused by sulfur poisoning and hydrothermal aging, which coexist in diesel vehicle after-treatment systems, complicating its actual deactivation. Activity evaluation and characterization tests were used to investigate the coupled deactivation properties as well as sulfur poisoning and hydrothermal aging mechanisms of the Cu-SSZ-13 SCR catalyst. The activity evaluation tests included the standard SCR reaction and NH<sub>3</sub> oxidation tests, and the characterization tests included the NH<sub>3</sub>-TPD test, SO<sub>2</sub>-TPD test, and NO + NH<sub>3</sub> TPR test. The sulfur-poisoned active sites of Cu-SSZ-13 inhibited the migration of ZCuOH to Z<sub>2</sub>Cu in the subsequent hydrothermal aging, resulting in lower SCR activity at high temperatures than the samples hydrothermally aged only. The migration of ZCuOH to Z<sub>2</sub>Cu caused by hydrothermal aging increased the sulfur resistance of the active sites, decreased the sulfur species production, and increased the SCR activity at low temperatures. For the samples that hydrothermally aged with SO<sub>2</sub> at 650 °C, some sulfur species were formed, which significantly affected the SCR activity in the whole temperature range. At 750 °C, the low-temperature SCR activity showed no reduction. At 850 °C, SO<sub>2</sub> promoted the formation of copper oxide. These research conditions closely resemble real-world aging conditions, refining the mechanism of coupled deactivation due to hydrothermal aging and sulfur poisoning in the Cu-SSZ-13 catalyst.</div></div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":"15 23","pages":"Pages 7098-7109"},"PeriodicalIF":4.2,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145584704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Biomass-derived ethylene glycol (EG) contains 1,2-propylene glycol (PG) and 1,2-butylene glycol (BG), which are difficult to isolate via traditional techniques. This paper presents a modification strategy of a zeolite catalyst through acid-etching and coke-deposition to achieve selective transformation of these diols. The diameters of mesopores were increased after the treatment with HCl, significantly enhancing the transport of the substrate and improving the conversions of PG and BG. According to the FTIR, Raman, NH3-TPD, and titration results, the coke contained ether, aromatic, and phenolic groups. The coke selectively deactivated the strong Lewis acid sites over zeolite, suppressing the acetalization and ketalization reactions of EG. Meanwhile, the dehydration reactions of PG and BG as well as ring-closure and oligomerization reactions of EG were less dependent on these Lewis acid sites, and thereby these reactions were less affected by the deposition of coke. Therefore, the undesirable conversion of EG was inhibited without suppressing the reactivity of PG and BG. The reaction products were efficiently isolated from EG via a single-stage distillation process, and the purity and recovery of EG reached 90.3% and 93%. This modified catalyst demonstrated excellent stability over multiple reaction cycles, and it can be regenerated via simple calcination.
{"title":"Modification of zeolite via acid-etching and coke-deposition for the selective transformation of propylene glycol and butylene glycol in ethylene glycol","authors":"Shuo Ai , Yihan Yang , Linghui Liu , Wanguo Yu","doi":"10.1039/d5cy01073j","DOIUrl":"10.1039/d5cy01073j","url":null,"abstract":"<div><div>Biomass-derived ethylene glycol (EG) contains 1,2-propylene glycol (PG) and 1,2-butylene glycol (BG), which are difficult to isolate <em>via</em> traditional techniques. This paper presents a modification strategy of a zeolite catalyst through acid-etching and coke-deposition to achieve selective transformation of these diols. The diameters of mesopores were increased after the treatment with HCl, significantly enhancing the transport of the substrate and improving the conversions of PG and BG. According to the FTIR, Raman, NH<sub>3</sub>-TPD, and titration results, the coke contained ether, aromatic, and phenolic groups. The coke selectively deactivated the strong Lewis acid sites over zeolite, suppressing the acetalization and ketalization reactions of EG. Meanwhile, the dehydration reactions of PG and BG as well as ring-closure and oligomerization reactions of EG were less dependent on these Lewis acid sites, and thereby these reactions were less affected by the deposition of coke. Therefore, the undesirable conversion of EG was inhibited without suppressing the reactivity of PG and BG. The reaction products were efficiently isolated from EG <em>via</em> a single-stage distillation process, and the purity and recovery of EG reached 90.3% and 93%. This modified catalyst demonstrated excellent stability over multiple reaction cycles, and it can be regenerated <em>via</em> simple calcination.</div></div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":"15 23","pages":"Pages 7120-7128"},"PeriodicalIF":4.2,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145584673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sónia F. G. Santos , Paul James , Rajesh Reddy Bommareddy , Yunhong Jiang , Jun Li , Chun Li , Warispreet Singh , Meilan Huang
Cytochrome P450 cinnamate 4-hydroxylase (C4H) is a pivotal enzyme in the phenylpropanoid pathway, playing a critical role in regulating lignin biosynthesis in plants. In contrast to the hydroxylation reactions catalyzed by human P450 enzymes, which have been extensively studied, the mechanistic understanding of plant P450-mediated hydroxylation of aromatic substrates remains limited. In this study, using comprehensive atomistic molecular dynamics (MD) simulations, we elucidated the binding pose of the native substrate trans-cinnamic acid and identified key residues contributing to the substrate specificity of the enzyme, which include Arg213 and a conserved hydrophobic pocket comprising Val118, Phe119, Val301, Ala302, Ile367 and Phe484. Additionally, we investigated the catalytic mechanism using hybrid quantum mechanics/molecular mechanics (QM/MM) calculations, evaluating all plausible C4H-catalysed pathways for aromatic hydroxylation. Our results reveal that among all investigated mechanisms, the most favourable pathway involves direct hydroxylation via electrophilic attack coupled with a proton shuttle. These findings provide valuable insights into the catalytic mechanism of C4H, which would pave the way for modifying lignin biosynthesis to regulate various lignin contents in plants, unlocking its potential applications in sustainable bioremediation and biomanufacturing.
{"title":"Hydroxylation mechanism of lignin-derived aromatic substrates catalyzed by plant P450 cinnamate 4-hydroxylase","authors":"Sónia F. G. Santos , Paul James , Rajesh Reddy Bommareddy , Yunhong Jiang , Jun Li , Chun Li , Warispreet Singh , Meilan Huang","doi":"10.1039/d5cy00502g","DOIUrl":"10.1039/d5cy00502g","url":null,"abstract":"<div><div>Cytochrome P450 cinnamate 4-hydroxylase (C4H) is a pivotal enzyme in the phenylpropanoid pathway, playing a critical role in regulating lignin biosynthesis in plants. In contrast to the hydroxylation reactions catalyzed by human P450 enzymes, which have been extensively studied, the mechanistic understanding of plant P450-mediated hydroxylation of aromatic substrates remains limited. In this study, using comprehensive atomistic molecular dynamics (MD) simulations, we elucidated the binding pose of the native substrate <em>trans</em>-cinnamic acid and identified key residues contributing to the substrate specificity of the enzyme, which include Arg213 and a conserved hydrophobic pocket comprising Val118, Phe119, Val301, Ala302, Ile367 and Phe484. Additionally, we investigated the catalytic mechanism using hybrid quantum mechanics/molecular mechanics (QM/MM) calculations, evaluating all plausible C4H-catalysed pathways for aromatic hydroxylation. Our results reveal that among all investigated mechanisms, the most favourable pathway involves direct hydroxylation <em>via</em> electrophilic attack coupled with a proton shuttle. These findings provide valuable insights into the catalytic mechanism of C4H, which would pave the way for modifying lignin biosynthesis to regulate various lignin contents in plants, unlocking its potential applications in sustainable bioremediation and biomanufacturing.</div></div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":"15 23","pages":"Pages 7067-7078"},"PeriodicalIF":4.2,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145584701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号