Reaction Chemistry & Engineering最新文献

{"title":"Combination of near-infrared spectroscopy and a transient flow method for efficient kinetic analysis of the Claisen rearrangement†","authors":"Yoshihiro Takebayashi, Kiwamu Sue and Sho Kataoka","doi":"10.1039/D4RE00301B","DOIUrl":"10.1039/D4RE00301B","url":null,"abstract":"<p >Kinetic analysis of the Claisen rearrangement of allyl phenyl ether (APE) to 2-allylphenol was conducted in pressurized <em>N</em>-methylpyrrolidone (NMP) at various temperatures from 240 to 280 °C using an automated flow reactor. Rapid inline analysis using a compact near-infrared (NIR) spectrometer coupled with a flow rate ramp as a reciprocal function of the experimental time allowed high-density data acquisition (900 points in 15 min) of the conversion of APE over residence times ranging from 0.8 to 10.3 min. Inline NIR monitoring was also employed to measure the residence time of the NMP solution in the reactor. The residence time was shown to decrease by 26% with increasing temperature from 20 to 300 °C due to the thermal expansion of the solution. The APE conversion exhibited first-order kinetics with an activation energy of 137 ± 1 kJ mol<small>⁻¹</small> and a pre-exponential factor of 7.3 × 10<small>¹⁰</small> s<small>⁻¹</small>. The result of the flow rate ramp experiment was consistent with that of the temperature ramp experiment, while the latter gave a continuous Arrhenius plot in a wider temperature range from 230 to 290 °C. The rate constant in NMP was found to be 10 and 1.5 times smaller than those reported in subcritical water and alcohol solvents, respectively.</p>","PeriodicalId":101,"journal":{"name":"Reaction Chemistry & Engineering","volume":" 11","pages":" 2975-2983"},"PeriodicalIF":3.4,"publicationDate":"2024-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949278","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}

{"title":"Continuous flow synthesis and crystallization of modafinil: a novel approach for integrated manufacturing†","authors":"Diana V. Silva-Brenes, Shailesh Agrawal, Vilmalí López-Mejías, Jorge Duconge, Cornelis P. Vlaar, Jean-Christophe M. Monbaliu and Torsten Stelzer","doi":"10.1039/D4RE00273C","DOIUrl":"10.1039/D4RE00273C","url":null,"abstract":"<p >This study reports efforts toward the integrated advanced manufacturing of the anti-narcoleptic drug modafinil. It showcases a holistic approach from flow synthesis to purification <em>via</em> continuous crystallization. The integration strategy included a necessary optimization of the reported flow synthesis for modafinil, enabling prolonged operation and consistent crude quality. The reactor effluents were subsequently processed downstream for purification utilizing two single stage mixed suspension mixed product removal crystallizers. The first stage was an antisolvent cooling crystallization, providing refined modafinil with &gt;98% yield. The second cooling crystallization delivered crystalline modafinil with &gt;99% purity in the required polymorphic form I suitable for formulation.</p>","PeriodicalId":101,"journal":{"name":"Reaction Chemistry & Engineering","volume":" 10","pages":" 2728-2739"},"PeriodicalIF":3.4,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949272","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}

{"title":"Facile fabrication of graphitic carbon nitride/polydopamine/polyurethane foam as a floating photocatalyst for synthetic dye remediation†","authors":"Indra J. Budiarso, Shusaku Fujita, Shota Saito, Hermawan Judawisastra, Kotaro Takeyasu and Arie Wibowo","doi":"10.1039/D4RE00193A","DOIUrl":"10.1039/D4RE00193A","url":null,"abstract":"<p >Graphitic carbon nitride (GCN) has attracted much interest in photocatalytic wastewater treatment. However, GCN sinks when applied in wastewater and photogenerated electron–hole (e–h) pairs are easily recombined. In this work, a GCN-based floating photocatalyst with polyurethane foam (PUF) as a floating support and polydopamine (PDA) as the immobilization anchor and photogenerated electron acceptor was prepared <em>via</em> a one-step immobilization process. Compared to the sample prepared <em>via</em> a two-step immobilization process (PUF/PDA/GCN-2), the sample prepared through the one-step immobilization process (PUF/PDA/GCN-1) exhibited a more uniform distribution of GCN particles (as confirmed from SEM images) with a GCN loading content (5.0%) four times greater than that for PUF/PDA/GCN-2 (1.3%), as shown in TGA results. Interestingly, the addition of PDA could increase the photocatalytic performance more than twice that of the sample without PDA addition. Moreover, 4.7 × 10<small>⁻⁵</small> mmol dye could be degraded per mg of catalyst on PUF/PDA/GCN-1, which is superior to several existing GCN-based floating photocatalysts. This phenomenon was triggered by efficient e–h pair separation, as suggested by the photoluminescence (PL) spectrum and uniform small-sized GCN distribution. The interaction mechanism among PUF, PDA, and GCN is also proposed based on FTIR and XPS studies as well as the photocatalytic mechanism. The successful preparation of floating photocatalysts through a cheap and facile route was thus demonstrated and has potential for large-scale commercialization.</p>","PeriodicalId":101,"journal":{"name":"Reaction Chemistry & Engineering","volume":" 10","pages":" 2718-2727"},"PeriodicalIF":3.4,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949273","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}

{"title":"A novel magnetic nanoparticle as an efficient and recyclable heterogeneous catalyst for the Suzuki cross-coupling reaction†","authors":"Hui Jin, Mengyu Cui, Peiwen Liu, Zhuo Wang, Tongxia Jin, Yonghui Yang, Weiping Zhu and Xuhong Qian","doi":"10.1039/D4RE00226A","DOIUrl":"10.1039/D4RE00226A","url":null,"abstract":"<p >Heterogeneous palladium catalysts are widely used in catalytic hydrogenation, oxidation, reduction, and coupling reactions due to their good stability, recyclability, and reusability. Based on the palladium ion fluorescent probe, a novel magnetically recyclable heterogeneous palladium catalyst Fe<small>₃</small>O<small>₄</small>@FSM@Pd was constructed and characterized, which is highly efficient and reusable for the Suzuki–Miyaura cross-coupling reaction. The subsequent series of Maitlis' filtration test, catalyst concentration–yield kinetic experiments, and phase trajectory experiments further demonstrated that Fe<small>₃</small>O<small>₄</small>@FSM@Pd catalyzed through a heterogeneous mechanism under selected reaction conditions. In addition, Fe<small>₃</small>O<small>₄</small>@FSM@Pd was applied to catalyze the synthesis of five intermediates of active pharmaceutical ingredients (APIs): valsartan, sonidegib, erdafitinib, tubulin inhibitor, and lumacaftor. Importantly, the palladium residue in the API intermediates synthesized with Fe<small>₃</small>O<small>₄</small>@FSM@Pd as catalyst was less than 1 ppm. Furthermore, Fe<small>₃</small>O<small>₄</small>@FSM@Pd is stable and can be reused at least 5 times without losing activity.</p>","PeriodicalId":101,"journal":{"name":"Reaction Chemistry & Engineering","volume":" 11","pages":" 2954-2962"},"PeriodicalIF":3.4,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949275","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}

{"title":"Hydrogen production by aqueous phase reforming of methanol over stable C-modified NiMgAl hydrotalcite catalyst","authors":"Yuankai Huang, Jiahao Huang, Riyang Shu, Libin Lei, Qingbin Song, Zhipeng Tian, Chao Wang and Ying Chen","doi":"10.1039/D4RE00308J","DOIUrl":"10.1039/D4RE00308J","url":null,"abstract":"<p >Although catalytic aqueous phase reforming (APR) of methanol is a promising hydrogen production method, Ni-based catalysts suffer from low catalyst hydrothermal stability due to severe active metal leaching. To address this problem, NiMgAl hydrotalcite is applied as a support and citric acid as a carbon source to prepare a C-modified NiMgAl hydrotalcite catalyst, and its reaction performance for hydrogen production <em>via</em> methanol APR is evaluated. The introduction of carbon species enhances the interaction between surface Ni and the Mg(Ni,Al)O support, thereby increasing the stability of the catalyst. This enhancement induces the migration of Ni to the catalyst surface, promoting the formation of Ni clusters and exposing more active sites on the catalyst surface. Simultaneously, the carbon modification resulted in smaller Ni particle sizes in the catalyst, which facilitated the reduction of Ni clusters on the catalyst surface. Additionally, part of the NiO was reduced to Ni monomers by carbon and subsequently stabilized, enhancing the activity of the Ni metal on the surface. Compared with the carbon-free NiMgAl catalyst, the C-modified NiMgAl catalyst exhibited an increase in methanol conversion and total hydrogen yield of 83.19% and 82.78%, respectively. Over 17 cyclic reactions are achieved without a sharp decline in hydrogen production yield, implying good hydrothermal stability by anchoring Ni metal sites on the C-modified NiMgAl catalyst.</p>","PeriodicalId":101,"journal":{"name":"Reaction Chemistry & Engineering","volume":" 10","pages":" 2762-2772"},"PeriodicalIF":3.4,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949274","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}

{"title":"Effect of defects and framework Sn on the stability and activity of Pt clusters for ethane dehydrogenation in chabazite zeolite†","authors":"Sanjana Srinivas, Dionisios G. Vlachos and Stavros Caratzoulas","doi":"10.1039/D4RE00187G","DOIUrl":"10.1039/D4RE00187G","url":null,"abstract":"<p >With increasing interest in new catalytic materials based on atomically dispersed transition metals on various supports (<em>e.g.</em>, zeolites or oxides), it is necessary to have an atomic level understanding of the factors that determine their structural and electronic properties as well as catalytic activity. Encapsulated Pt atoms and sub-nanometer Pt clusters in Sn-substituted zeolitic frameworks have demonstrated extended catalytic stability and remarkable selectivity for alkane dehydrogenation to alkenes. Despite efforts to characterize these materials, the bonding environment of the dispersed atoms in the presence of framework Sn or of defect silanols is uncertain. We have employed <em>ab initio</em> molecular dynamics simulations and electronic structure calculations to identify and characterize electronically stable Pt active site motifs in chabazite (CHA) and Sn-CHA at low Pt loadings. The activity of several active site motifs was assessed by microkinetic simulations. We demonstrate that framework Sn and silanol defects can promote the dispersion of Pt species. Unexpectedly, we find that in the presence of silanol nests, the dispersed Pt species statistically prefer to coordinate with the silanols and not with the framework Sn. We show that Pt and Sn are bonded <em>via</em> a 3-center-4-electron bond (O:–Sn–:Pt), affirm the absence of Pt–O–Sn bonding, and thus resolve the ambiguity related to the coordination of Pt to framework Sn. We predict that the O:–Sn–:Pt and Sn–O–Pt–Pt–Si bonding motifs in Sn-CHA are stable and active for ethane dehydrogenation. We relate our findings and conclusions to recent experimental characterization of Pt in Sn-BEA zeolite, point out the close alignment in several aspects and suggest that the effect of framework Sn on the dispersion of low nuclearity Pt species and on the formation of stable and efficient active sites should be largely independent of the framework itself.</p>","PeriodicalId":101,"journal":{"name":"Reaction Chemistry & Engineering","volume":" 10","pages":" 2784-2793"},"PeriodicalIF":3.4,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/re/d4re00187g?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949277","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}

{"title":"Kinetics of thermal dry reforming of methane for syngas production and solid carbon capture†","authors":"Manas Mokashi, Akash Bhimrao Shirsath, Sinan Demir, Ahmet Çelik, Patrick Lott, Steffen Tischer and Olaf Deutschmann","doi":"10.1039/D4RE00312H","DOIUrl":"10.1039/D4RE00312H","url":null,"abstract":"<p >Dry reforming of CH<small>₄</small>, either by co-feeding CH<small>₄</small> and CO<small>₂</small> from waste streams or directly using biogas, has potential as a CO<small>₂</small>-sink. This study investigates entirely thermal, catalyst-free dry reforming in a tubular flow reactor, aiming for syngas production with concurrent carbon capture. Kinetic modelling couples an elementary step-based gas-phase mechanism with a carbon deposition model. One-dimensional numerical simulations of the flow reactor are compared with experimental measurements. For this, operating conditions are widely varied, in particular temperature (1273 K to 1873 K), residence time (1 to 7 seconds), and CH<small>₄</small> : CO<small>₂</small> molar feed ratio (1 to 4). Two temperature regimes are identified, with varying dominance of the reverse water-gas shift and CH<small>₄</small> pyrolysis reactions. Above 1673 K, CO<small>₂</small> is fully consumed, independent of residence time and feed composition. Optimized operating parameters result in a H<small>₂</small>/CO ratio of 2 in the effluent gas stream, <em>e.g.</em> as commonly desired for methanol and oxo-alcohol synthesis. Notably, under such optimized conditions, only a minor share of carbonaceous species remains in the gas-phase as hydrocarbons, while 33% of the CH<small>₄</small>-borne carbon is transformed into CO and 48% of CH<small>₄</small>-borne carbon is captured as solid carbon.</p>","PeriodicalId":101,"journal":{"name":"Reaction Chemistry & Engineering","volume":" 11","pages":" 2902-2914"},"PeriodicalIF":3.4,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/re/d4re00312h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949279","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}

{"title":"3D printing for safe organic synthesis in mixed liquid/gas-phase chemistry","authors":"Victoria A. Korabelnikova, Yulia V. Gyrdymova, Evgeniy G. Gordeev, Anton N. Potorochenko, Konstantin S. Rodygin, Valentine P. Ananikov","doi":"10.1039/d4re00249k","DOIUrl":"https://doi.org/10.1039/d4re00249k","url":null,"abstract":"Working with liquid/gas-phase systems in chemical laboratories is a fundamentally important but difficult operation, mainly due to the explosion risk associated with conventional laboratory equipment. Such systems, in the case of improper operation or destruction, may pose a significant threat to researchers. To address this challenge, our work explores the potential of additive technologies, particularly fused filament fabrication (FFF), for improving laboratory safety. We have successfully utilized FFF to produce compact safety modules, including integrated bursting discs, which can be easily made on demand and adapted to various types of reaction setups. Compared with traditional glassware, these modules, when integrated with laboratory reactors, significantly enhance operational safety. Our research highlights that in the event of excessive internal pressure, 3D-printed reactor parts undergo delamination and cracking of the wall, a mechanism that notably avoids the creation of hazardous fragments from the whole reaction vessel. This study demonstrated the efficiency and safety of additively manufactured reactors in organic synthesis using a variety of gases, including acetylene, carbon dioxide, and hydrogen. We systematically tested these reactors in vinylation and azide–alkyne cycloaddition reactions. Our findings confirm that 3D-printed reactors not only provide increased safety during pressurized operations but also maintain operational efficiency. The discussed approach offers a transformative solution for safer and more effective handling of gaseous reagents in laboratory settings, marking a significant advancement in flexible reactor design and chemical laboratory safety practices.","PeriodicalId":101,"journal":{"name":"Reaction Chemistry & Engineering","volume":"294 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949280","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}

{"title":"Modular 3D printed flow system for efficient one-step synthesis of phenyl-functionalised silica-coated superparamagnetic iron oxide nanoparticles†","authors":"Andrea du Preez, André M. Strydom, Derek T. Ndinteh and Elize Smit","doi":"10.1039/D4RE00242C","DOIUrl":"10.1039/D4RE00242C","url":null,"abstract":"<p >Iron oxide nanoparticles (IONPs) are used in various applications, including magnetic solid phase extraction (MSPE), due to advantages such as excellent adsorption efficiency and easy separation from varied matrices using an external magnet. Here we introduce a low-cost 3D-printed modular flow system for the automated synthesis of phenyl-functionalised silica-coated iron oxide nanoparticles. This system consists of 3D-printed polypropylene (PP) reactors with varying geometries connected in series to synthesise bare IONPs, silica-coated IONPs, or phenyl-functionalised silica-coated IONPs using laminar flow regimes. The simplicity, affordability, robustness, and customisability of the system were illustrated. The synthesised IONPs were characterised using Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), zeta potential, powder X-ray diffraction (XRD), thermogravimetric analysis (TGA) and vibrating sample magnetometry (VSM). The continuous flow system resulted in fast reactions under ambient conditions, with a production rate of approximately 5 mg min<small>⁻¹</small>. The produced IONPs were small (∼10 nm), resulting in a larger surface-to-volume ratio. Furthermore, the synthesised IONPs retained large enough saturation magnetisation values, which together with larger surface-to-volume ratios, is ideal for MSPE.</p>","PeriodicalId":101,"journal":{"name":"Reaction Chemistry & Engineering","volume":" 10","pages":" 2740-2749"},"PeriodicalIF":3.4,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/re/d4re00242c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141885123","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}

{"title":"Propane dehydrogenation on an extra-framework and framework-embedded metal site within ZSM-5 zeolite from first-principles microkinetic simulations†","authors":"Yujue Du, Wende Hu, Yunlei Chen, Chuanming Wang and Weimin Yang","doi":"10.1039/D4RE00269E","DOIUrl":"10.1039/D4RE00269E","url":null,"abstract":"<p >Isolated single metal site within zeolite exhibits promising catalytic performances towards propane dehydrogenation (PDH); however, the underlying relationship between the local structure of the intrinsic site and the catalytic behavior remains elusive. Herein, the possible structures, relative stabilities and catalytic performances of three isolated single metal cations (M<small>²⁺</small>, M is Co, Ni, or Cu) within ZSM-5 zeolite were theoretically investigated by combining density functional theory calculations and microkinetic simulations. Both the extra-framework site and the framework-embedded site were taken into account for the sitting of a single metal cation. The isolated divalent M<small>²⁺</small> sites are more stable than the corresponding univalent MOH<small>⁺</small> sites and both kinds of structures display distinct dependence of stability on temperature. The stepwise pathway rather than the concerted pathway is followed for direct PDH under the reaction conditions of 853 K. Microkinetic simulations reveal that PDH activity increases in the sequence of Co &lt; Ni &lt; Cu within the same local environment of the active site. At the framework-embedded site, the divalent M<small>²⁺</small> cations exhibit higher catalytic activity compared to univalent MOH<small>⁺</small> cations; on the contrary, the MOH<small>⁺</small> motifs are more active than the divalent M<small>²⁺</small> ones at the extra-framework site. It seems that the dissociative adsorption enthalpy of propane on isolated metal sites can be utilized to describe PDH activity variation with different metal cations. Simulation results demonstrate that the framework-embedded single Cu site derived from the silanol nest within ZSM-5 zeolite exhibits outstanding PDH activity, while it may suffer from the weakness of stability. This work thus highlights the importance of the local environment of single metal active sites within zeolites and may open up novel avenues for the screening of high-performance catalysts for PDH.</p>","PeriodicalId":101,"journal":{"name":"Reaction Chemistry & Engineering","volume":" 11","pages":" 2892-2901"},"PeriodicalIF":3.4,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141885125","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}