Reactions最新文献_第5页

Co-Hydroprocessing of Fossil Middle Distillate and Bio-Derived Durene-Rich Heavy Ends under Hydrotreating Conditions 在加氢处理条件下化石中间馏分与生物衍生的富均烯重端共加氢处理

Reactions Pub Date : 2023-09-21 DOI: 10.3390/reactions4030032

David Graf, Johannes Waßmuth, Reinhard Rauch

{"title":"Co-Hydroprocessing of Fossil Middle Distillate and Bio-Derived Durene-Rich Heavy Ends under Hydrotreating Conditions","authors":"David Graf, Johannes Waßmuth, Reinhard Rauch","doi":"10.3390/reactions4030032","DOIUrl":"https://doi.org/10.3390/reactions4030032","url":null,"abstract":"Methanol-to-gasoline (MTG) and dimethyl ether-to-gasoline (DTG), as industrially approved processes for producing greenhouse gas-neutral gasoline, yield byproducts rich in heavy mono-ring aromatics such as 1,2,4,5-tetramethylbenzene (durene). Due to its tendency to crystallize and the overall poor fuel performance, the heavy fuel fraction is usually further processed using after-treatment units designed for this purpose. This research article discusses the co-hydroprocessing (HP) of bio-derived heavy gasoline (HG) with fossil middle distillate (MD), drawing on available refinery hydrotreaters. Co-HP experiments were conducted in a laboratory-scale fixed bed reactor using an industrial CoMo/γ-Al2O3 catalyst, varying the space-time between 0.7 and 4.0 cmCat3 h cmFeed−3 and the reaction temperature between 340 and 390 °C. In addition to the durene conversion, special attention was paid to the octane and cetane numbers (CN) of gasoline and MD, respectively. A six-lump model with ten parameters was developed to predict relevant fuel yields dependent on the process conditions. Under stable catalyst conditions, C10 aromatic conversions of more than 60% were obtained, while the CN remained close to that of pure MD. Harsh process conditions increased the gasoline yield up to 20% at the cost of MD, while the kerosene yield remained almost constant. With an optimized lumping model, fuel yields could be predicted with an R2 of 0.998. In this study, co-HP heavy aromatic-rich MTG/DTG fuels with fossil MD were proven to be a promising process strategy compared to a stand-alone after-treatment.","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136237018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparative Analysis of Bio- and Chemo-Catalysts for the Synthesis of Flavour Compound Hexanal from Linoleic Acid 亚油酸合成风味化合物己醛的生物与化学催化剂对比分析

Reactions Pub Date : 2023-09-18 DOI: 10.3390/reactions4030031

Jan Drönner, Valentin Gala Marti, Simone Bandte, Anna Coenen, Ulrich Schörken, Matthias Eisenacher

{"title":"Comparative Analysis of Bio- and Chemo-Catalysts for the Synthesis of Flavour Compound Hexanal from Linoleic Acid","authors":"Jan Drönner, Valentin Gala Marti, Simone Bandte, Anna Coenen, Ulrich Schörken, Matthias Eisenacher","doi":"10.3390/reactions4030031","DOIUrl":"https://doi.org/10.3390/reactions4030031","url":null,"abstract":"Hexanal, hexenal, nonenal and their corresponding alcohols are used as green notes in the fragrance and flavour industry. The production of bio-based hexanal starts from linoleic acid, which can be obtained from sunflower or safflower oil. The biocatalytic process utilizes C13-specific lipoxygenase (LOX) for hydroperoxidation and consecutive splitting with hydroperoxide lyase (HPL). In this study, we investigated the chemical splitting of the LOX product 13-HPODE in comparison to HPL catalysis. In addition, 13-HPODE was synthesized using enriched linoleic acid from safflower oil. Varying amounts of soybean flour suspension as a source of LOX yielded up to 60% HPODE with a regioselectivity of 92% towards 13-HPODE. Using low-toxicity Lewis acids like AlCl3 and ZrCl4, cleavage of the produced 13-HPODE was possible. A maximum hexanal yield of 22.9% was reached with AlCl3 under mild reaction conditions, though product degradation was an interfering process. Comparative trials with N-terminal truncated HPL from papaya revealed hexanal recovery within a comparable range. Additionally, we successfully demonstrated the viability of Hock rearrangement of 13-HPODE through heterogeneous catalysts. Notably, Beta zeolite and Montmorillonite K10 exhibited a turnover frequency (TOF) on par with common heterogeneous catalysts employed in industrial processes.","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135202746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Full Factorial Design Synthesis of Silver Nanoparticles Using Origanum vulgare 全因子设计合成银纳米颗粒的研究

Reactions Pub Date : 2023-09-14 DOI: 10.3390/reactions4030030

Nickolas Rigopoulos, Christina Megetho Gkaliouri, Viktoria Sakavitsi, Dimitrios Gournis

{"title":"Full Factorial Design Synthesis of Silver Nanoparticles Using Origanum vulgare","authors":"Nickolas Rigopoulos, Christina Megetho Gkaliouri, Viktoria Sakavitsi, Dimitrios Gournis","doi":"10.3390/reactions4030030","DOIUrl":"https://doi.org/10.3390/reactions4030030","url":null,"abstract":"Green synthesis of silver nanoparticles (AgNPs) involves a reduction reaction of a metal salt solution mixed with a plant extract. The reaction yield can be controlled using several independent factors, such as extract and metal concentration, temperature, and incubation time. AgNPs from Origanum vulgare (oregano) were synthesized in the past. However, no investigations were performed on the combined effects of independent factors that affect the synthesis. In this work, silver nitrate, oregano extract, and sodium hydroxide (NaOH) concentrations were chosen as the independent factors, and full factorial design under Response Surface Methodology was employed. UV–Vis absorbance spectroscopy, X-ray Powder Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR) were used to characterize the nanoparticles. A Voigt function was fitted on the measured UV–Vis spectra. The fitting parameters of the Voigt function, peak wavelength, area, and Full Width at Half Maximum, were used as the responses. A quadratic model was fitted for the peak wavelength and area. The NaOH concentration proved to be the dominant factor in nanoparticle synthesis. UV–Vis absorbance showed a characteristic plasmon resonance of AgNPs at 409 nm. XRD verified the crystallinity of the nanoparticles and FTIR identified the ligands involved.","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134911956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Recent Advances in the Synthesis of Pyrazole Derivatives: A Review 吡唑衍生物的合成研究进展

Reactions Pub Date : 2023-09-05 DOI: 10.3390/reactions4030029

Issam Ameziane El Hassani, Khouloud Rouzi, Hamza Assila, K. Karrouchi, M. Ansar

{"title":"Recent Advances in the Synthesis of Pyrazole Derivatives: A Review","authors":"Issam Ameziane El Hassani, Khouloud Rouzi, Hamza Assila, K. Karrouchi, M. Ansar","doi":"10.3390/reactions4030029","DOIUrl":"https://doi.org/10.3390/reactions4030029","url":null,"abstract":"Pyrazole, characterized by a five-membered heterocyclic structure featuring two neighboring nitrogen atoms, serves as a core element. Pyrazoles hold a privileged status as versatile frameworks in various sectors of the chemical industry, including medicine and agriculture. Previous reviews have extensively highlighted the significance of pyrazoles and their diverse biological activities, encompassing roles such as antituberculosis, antimicrobial, antifungal, anti-inflammatory, anticancer, and antidiabetic agents. Consequently, they have garnered substantial interest from researchers. The aim of this review is to offer a comprehensive overview of the published research related to the synthesis of pyrazole derivatives, encompassing a discussion of diverse methods for accessing the pyrazole moiety. These methods span from utilizing transition-metal catalysts and photoredox reactions to employing one-pot multicomponent processes, novel reactants, and innovative reaction types. It encompasses studies conducted by numerous scientists worldwide, showcasing collective efforts in advancing the methodologies and applications of pyrazole derivatives.","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80389338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Catalytic Valorisation of Biomass-Derived Levulinic Acid to Biofuel Additive γ-Valerolactone: Influence of Copper Loading on Silica Support 生物质衍生乙酰丙酸对生物燃料添加剂γ-戊内酯的催化增值:铜负载对二氧化硅载体的影响

Reactions Pub Date : 2023-09-05 DOI: 10.3390/reactions4030028

Rajender Boddula, Paramasivam Shanmugam, Rajesh K. Srivatsava, Nabila Tabassum, Ramyakrishna Pothu, R. Naik, Aditya Saran, B. Viswanadham, A. B. Radwan, N. Al-Qahtani

{"title":"Catalytic Valorisation of Biomass-Derived Levulinic Acid to Biofuel Additive γ-Valerolactone: Influence of Copper Loading on Silica Support","authors":"Rajender Boddula, Paramasivam Shanmugam, Rajesh K. Srivatsava, Nabila Tabassum, Ramyakrishna Pothu, R. Naik, Aditya Saran, B. Viswanadham, A. B. Radwan, N. Al-Qahtani","doi":"10.3390/reactions4030028","DOIUrl":"https://doi.org/10.3390/reactions4030028","url":null,"abstract":"γ-valerolactone (GVL) is a crucial chemical feedstock used in the production of fuel additives, renewable fuels, and fine chemicals alternative to petroleum-based solvents and chemicals, supporting the transition to sustainable energy solutions. It is promptly acquired by hydrogenating levulinic acid (LA) in a gaseous or liquid phase with a homogeneous or heterogeneous catalyst using a variety of recognized catalytic processes. Herein, this work focuses on the use of silica-supported copper (Cu/SiO2) catalysts for the gas-phase hydrogenation of LA to GVL under mild reaction conditions. The study analyzes how copper loading can affect the catalytic activity of the Cu/SiO2, while the flow rate of LA, time-on-stream, reaction temperature, and LA concentration affect the catalytic efficiency. The SiO2 support’s various Cu loadings are crucial for adjusting the catalytic hydrogenation activity. One of the studied catalysts, a 5 wt% Cu/SiO2 catalyst, demonstrated ~81% GVL selectivity with ~78% LA conversion and demonstrated stability for ~8 h while operating at atmospheric pressure and temperature (265 °C) and 0.5 mL/h of LA flow rate. The ability to activate hydrogen, high amount of acidic sites, and surface area were all discovered to be advantageous for increased GVL selectivity.","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"123 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76261077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

One-Pot Synthesis of Stable Poly([c2]Daisy–chain Rotaxane) with Pseudo-Stopper via Metathesis Reaction and Thiol-Ene Reaction 通过复分解反应和巯基烯反应一锅合成具有伪塞的稳定聚([c2]菊链轮烷)

Reactions Pub Date : 2023-08-23 DOI: 10.3390/reactions4030027

Risako Kamoto, K. Onimura, K. Yamabuki

{"title":"One-Pot Synthesis of Stable Poly([c2]Daisy–chain Rotaxane) with Pseudo-Stopper via Metathesis Reaction and Thiol-Ene Reaction","authors":"Risako Kamoto, K. Onimura, K. Yamabuki","doi":"10.3390/reactions4030027","DOIUrl":"https://doi.org/10.3390/reactions4030027","url":null,"abstract":"Rotaxanes, known as supramolecular compounds, are expected to find applications in functional materials due to their high degree of freedom. However, their synthesis requires multistep reactions, and there is a demand for more convenient methods to synthesize rotaxane materials. In this study, we aimed to investigate a simpler method for synthesizing highly functional rotaxane materials and explore the diversity of molecular designs. To achieve this, we successfully synthesized a host–guest conjugated compound that incorporates both crown ether as the host unit and secondary ammonium salts as the guest unit within the same molecule. Subsequently, the metathesis reaction of these compounds, which construct [c2]daisy-chain rotaxanes, enabled the one-pot synthesis of a topological polymer called “poly([c2]daisy-chain rotaxane)” with a pseudo-stopper. This methodology achieves the stabilization and polymerization of rotaxanes simultaneously, contributing to the easy materialization of rotaxanes. Furthermore, the thiol-ene reaction achieved the extension of the distance between rotaxane units and provided a useful approach to diversify the design of functional materials with rotaxane structures.","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86280766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Various Techniques for the Synthesis of 2-Nitrophenylamino-1,4-naphthoquinone Derivatives 2-硝基苯胺-1,4-萘醌衍生物的各种合成技术

Reactions Pub Date : 2023-08-21 DOI: 10.3390/reactions4030026

E. Leyva, Silvia E. Loredo-Carrillo, Johana Aguilar

{"title":"Various Techniques for the Synthesis of 2-Nitrophenylamino-1,4-naphthoquinone Derivatives","authors":"E. Leyva, Silvia E. Loredo-Carrillo, Johana Aguilar","doi":"10.3390/reactions4030026","DOIUrl":"https://doi.org/10.3390/reactions4030026","url":null,"abstract":"Nitrated products are important since they are intermediates in the synthesis of other compounds, such as explosives, perfumes, dyes and plastics, among others, and they have an easy capacity to convert into other functional groups. The synthesis of compounds with biological activity that have a nitro group in their structure is relevant to improving and/or enhancing their effect. In this work, different methodologies for the nitration of naphthoquinone derivative compounds are presented. The nitration of 3-R-2-(phenylamino)-1,4-naphthoquinone derivatives was carried out with nitric acid and sulfuric acid; milder reaction conditions were also established by diluting the acids or performing the reaction with weaker acids. Other methodologies were tested using nitrate salts for mononitrate product synthesis. We used a solvent-free reaction with oxalic acid using 3-R-2-(phenylamino)-1,4-naphthoquinones (R=H, Br or Cl), noting that the electronegativity of the chlorine group is decisive for achieving nitration with good yields. Finally, a Michael addition was performed with some nitrated anilines. To obtain denitrated compounds in the ortho and para positions, the reaction with strong acids is feasible; however, for the formation of mononitrated products, the Michael-type addition is more convenient.","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82872772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Insight into the Physicochemical Properties of Co-Based Catalysts in Fischer–Tropsch Synthesis 费托合成中co基催化剂的物理化学性质研究

Reactions Pub Date : 2023-08-04 DOI: 10.3390/reactions4030025

Nothando C. Shiba, Xinying Liu, Yali Yao

{"title":"Insight into the Physicochemical Properties of Co-Based Catalysts in Fischer–Tropsch Synthesis","authors":"Nothando C. Shiba, Xinying Liu, Yali Yao","doi":"10.3390/reactions4030025","DOIUrl":"https://doi.org/10.3390/reactions4030025","url":null,"abstract":"The effect of the different supports and catalyst-reducing agents on the Fischer–Tropsch (FT) reaction was investigated. The large surface area SiO2 support with a smaller pore volume deposited fine, evenly distributed Co3O4. Cubic-shaped Co3O4 appeared in clusters on the TiO2 support, whereas Co3O4 existed as single large particles on the Al2O3 support. The activity data obtained were discussed in terms of cluster size, particle size, particle shape, and mass transport limitations. The SiO2-supported catalysts showed a higher activity for the formation of paraffinic products when reduced in H2 at 250 °C. This is attributed to the formation of the CoO-Co active bond, which enhanced the activation of CO and the hydrogenation reactions. A higher activity was observed for the TiO2-supported catalyst at a higher reduction temperature (350 °C) when the mass of Co metal was higher. It afforded more paraffinic products due to enhanced secondary hydrogenation of olefins at higher reaction rates. The large Co3O4 supported on Al2O3 showed the least activity at both reduction temperatures due to strong metal-support interactions. The H2-reduced catalysts exhibited superior activity compared to all the syngas-reduced catalysts. Syngas reduction led to surface carbon deposition and the formation of surface carbides which suppressed the hydrogenation reactions and are selective to olefinic products.","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78856961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Kinetics and Mechanism of Electrochemical Reactions Occurring during the Chromium Electrodeposition from Electrolytes Based on Cr(III) Compounds: A Literature Review 基于Cr(III)化合物的电解液电沉积铬的电化学反应动力学和机理:文献综述

Reactions Pub Date : 2023-08-03 DOI: 10.3390/reactions4030024

V. Protsenko

引用次数: 1

The Formation of Small Amounts of Cyclopropane during Pulsed Pyrolysis of C4–C5 Acyclic Alkanes in the Adiabatic Compression Reactor 绝热压缩反应器中C4-C5无环烷烃脉冲热解过程中少量环丙烷的生成

Reactions Pub Date : 2023-07-19 DOI: 10.3390/reactions4030023

I. Bilera

{"title":"The Formation of Small Amounts of Cyclopropane during Pulsed Pyrolysis of C4–C5 Acyclic Alkanes in the Adiabatic Compression Reactor","authors":"I. Bilera","doi":"10.3390/reactions4030023","DOIUrl":"https://doi.org/10.3390/reactions4030023","url":null,"abstract":"During high-temperature pulse pyrolysis of acyclic butanes and pentanes under adiabatic compression conditions, cyclopropane, a stressed cyclic hydrocarbon, was found among the reaction products in small quantities for the first time. The analysis of the reaction products was performed by gas chromatography using three capillary columns of different polarity, selectivity and sufficient efficiency. The identification of reaction products, including cyclopropane, was performed using retention times of individual substances and model mixtures, as well as comparing chromatograms with reference chromatograms from the literature and the ScanView Application Database. It was shown that the chromatographic peak attributed to cyclopropane could not be a ghost peak. Additional confirmation of this conclusion was obtained in a series of experiments on the pyrolysis of n-butane at a reduced initial temperature of the adiabatic compression reactor (from 120 °C to 50 °C) and a modified mode of GC analysis. Cyclopropane yields as a function of maximum temperature have a bell-shaped asymmetric dependence. The maximum value of the yield of cyclopropane increases with the transition from normal alkanes to isoalkanes, and from pentanes to butanes; for n-pentane, 0.009 wt. %, and for isobutene, ≈0.017 wt. %. During the pulse pyrolysis of isobutane, n-butane, isopentane and n-pentane, cyclopropane is not a primary product. Further theoretical and experimental studies are needed to establish the mechanism of cyclopropane formation during pyrolysis of C4–C5 acyclic alkanes.","PeriodicalId":20873,"journal":{"name":"Reactions","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81904449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0