Frontiers in Chemical Engineering最新文献

{"title":"Cu-alginate hydrogels in microfluidic systems: a sustainable catalytic approach for click chemistry","authors":"Arijana Ramšak, Martin Gazvoda, Igor Plazl, R. Ambrožič","doi":"10.3389/fceng.2024.1434131","DOIUrl":"https://doi.org/10.3389/fceng.2024.1434131","url":null,"abstract":"This work explores the innovative use of copper-alginate (Cu-alginate) hydrogels within microfluidic systems to catalyze dipolar cycloaddition reactions, emphasizing green chemistry principles and process intensification. Utilizing naturally occurring biopolymers, such as alginates, provides an environmentally friendly alternative to conventional catalyst supports due to their biocompatibility, biodegradability, and effective metal ion immobilization capabilities. The integration of these biopolymer-based catalysts into microfluidic devices allows for precise control over reaction conditions, leading to enhanced reaction kinetics and mass transfer efficiencies. Our results demonstrate that Cu-alginate hydrogels effectively catalyze the formation of 1,4-disubstituted 1,2,3-triazoles through [3 + 2] dipolar cycloaddition reactions with high regioselectivity and conversion. The microfluidic setup ensures rapid and efficient synthesis, surpassing traditional batch reaction methods in both reaction rate and environmental impact by reducing solvent usage and waste generation. Furthermore, the use of microfluidics contributes to the reproducibility and scalability of the synthesis process, important for industrial applications. The model-based design and its simulations have been employed to further understand and optimize the reaction system. Diffusion through the gel layer and catalytic reaction kinetics estimated from experimental data were included in the model, providing a theoretical foundation for a comprehensive process evaluation. This study not only advances the field of sustainable catalysis by demonstrating the practical utility of biopolymer-supported catalysts in microfluidic systems, but also sets the stage for further research into biopolymer applications in complex chemical syntheses.","PeriodicalId":510140,"journal":{"name":"Frontiers in Chemical Engineering","volume":"4 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141640842","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}

{"title":"A submerged draw down test calibration method for fully-coupled CFD-DEM modelling","authors":"Jacob G. Wasserfall, C.J. Coetzee, Chris J. Meyer","doi":"10.3389/fceng.2024.1376974","DOIUrl":"https://doi.org/10.3389/fceng.2024.1376974","url":null,"abstract":"A fully coupled computational fluid dynamics (CFD) and discrete element method (DEM) model was calibrated using a draw down test (DDT) under submerged conditions. Momentum smoothing and cell clustering were used to model particles that were larger than the cells. The DEM input parameter values were initially set equal to those calibrated for the dry conditions. Under submerged conditions, results showed that the particle-particle coefficient of friction and the drag modifier had an influence on the results. It was found that the drag modifier had to be calibrated, while the particle-particle coefficient of friction, calibrated under dry conditions, could be used for the submerged conditions. A vertical suction pipe validation experiment was conducted. The suction pipe had a constant diameter, but the fluid velocity and the distance the pipe opening was held from the granular bed were varied. The amount of mass (particles) removed as well as the size of the cavity that formed in the material bed were measured and compared to model predictions. The results showed that using the parameter values calibrated in the DDT, too much material was removed (error of 30%). Removing the drag modifier (setting it equal to unity) significantly improved the results (error of 6%). It is concluded that due to the difference in flow mechanism (particle-induced in the DDT versus fluid-induced in the suction pipe), the DDT is not a suitable experiment to calibrate the input parameter values for a suction pipe. It is proposed that the flow mechanism and dynamics of the granular material and the fluid in the calibration experiment should be similar to that of the final application being investigated.","PeriodicalId":510140,"journal":{"name":"Frontiers in Chemical Engineering","volume":"39 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141653751","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}

{"title":"The integrated microfluidic photocatalytic planar reactor under continuous operation","authors":"Xue-hui Ge, Nanjie Wei, Xinyue Hu, Qinyin Xie, Xiaoda Wang, Ling Li, Ting Qiu","doi":"10.3389/fceng.2024.1375071","DOIUrl":"https://doi.org/10.3389/fceng.2024.1375071","url":null,"abstract":"An integrated microfluidic planar reactor is essential for achieving efficient and enhanced photocatalytic water treatment. Optimization of catalysts is an area of intense study owing to the need to enhance the performances of microreactors. A high-efficiency photocatalytic microreactor is presented here by combining a planar microreactor with a high-efficiency photocatalyst. TiO2 nanoparticles doped with Y and Yb were prepared to improve the photocatalytic reaction efficiency. First, better performance is achieved with the Y, Yb/TiO2 and TiO2 microreactors than conventional bulk reactors because of good photodegradation and a high reaction rate. Then, the Y, Yb/TiO2 film microreactor exhibits not only efficient catalytic activity with UV light but also higher photocatalytic activity under visible light irradiation than that achieved by a TiO2 film microreactor. The reaction rate constant of the Y, Yb/TiO2 film microreactor is approximately 0.530 s–1, which is twice that of the TiO2 film microreactor. Moreover, the performances under continuous and intermittent reactions are compared to evaluate the stability of the microreactor, thereby building the foundation for practical application of continuous water treatment in the microreactor.The planar microreactor provides a convenient platform for studying photodegradation under various conditions, such as different temperatures, flow rates, light irradiation (UV and Vis), and reaction modes (continuous and intermittent).","PeriodicalId":510140,"journal":{"name":"Frontiers in Chemical Engineering","volume":" 37","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140691157","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}

{"title":"The effect of 1-deoxynojirimycin isolated from logging residue of Bagassa guianensis on an in vitro cancer model","authors":"Susanne Suely Santos da Fonseca, Thaíssa Vitória Portal Rodrigues, W. Pinheiro, Eliel Barbosa Teixeira, Kyouk Isabel Portilho dos Santos, Marcelli Geisse de Oliveira Prata da Silva, Amanda Marques De Sousa, Débora Monteiro Carneiro do Vale, Jaqueline Diniz Pinho, T. Araújo, A. Khayat, Antonio Pereira","doi":"10.3389/fceng.2024.1342755","DOIUrl":"https://doi.org/10.3389/fceng.2024.1342755","url":null,"abstract":"Introduction:Bagassa guianensis Aubl, a tree widely distributed in Brazil, significantly contributes to the furniture industry. Notably, it harbors the bioactive compound 1-deoxynojirimycin (1-DNJ), which is retrievable from timber residues and retains activity even days after wood extraction. This makes Bagassa guianensis a promising biological resource for anticancer therapy and pharmacology studies. This study delves into the in vitro antineoplastic actions of 1-DNJ, focusing on adenocarcinoma gastric cell lines (ACP02) and glioblastoma (A172).Methods: The effect of 1-DNJ on cell viability was evaluated after 72 hours of treatment in the ACP02 and A172 cell lines. We also assessed the effect of 1-DNJ on the pattern of cell migration, cell death, changes in the cell cycle by flow cytometry, the production of reactive oxygen, and its antioxidant capacity in the scavenging of free radicals.Results: Assessing cell viability after 72 h (about 3 days) of treatment reveals a remarkable reduction, particularly in glioblastoma cells (A172), exhibiting a lower IC50 compared to ACP02 and MRC5 (fibroblast derived from normal lung tissue) cell lines. This decreased viability correlates with reduced reactive oxygen species (ROS) production in both cell lines after the treatment with 1-DNJ. Furthermore, 1-DNJ induces cell cycle arrest, impedes cell migration, and prompts cell death in ACP02 and A172.Discussion: These findings support 1-DNJ as a potent antineoplastic agent, particularly efficacious against glioblastoma and gastric adenocarcinoma. Thus, unveiling the therapeutic potential of Bagassa guianensis Aubl for cancer treatment and expanding the horizons of bioeconomy applications.","PeriodicalId":510140,"journal":{"name":"Frontiers in Chemical Engineering","volume":"205 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140719871","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}

{"title":"Characterization of biochars of different origin and application to the anaerobic digestion of source-selected organic fraction of municipal solid waste under batch conditions and at different dosages","authors":"Marta García-Prats, D. González, Antoni Sánchez","doi":"10.3389/fceng.2024.1384495","DOIUrl":"https://doi.org/10.3389/fceng.2024.1384495","url":null,"abstract":"Anaerobic digestion (AD) is a wide-spread strategy to manage organic waste and recover valuable products but faces some limitations that could be overcome with additives like biochar (BC). The production of BC defines its properties, which in turn determine its effect on AD performance and methane yield. In this study, three biochars (BC1, BC2 and BC3) were characterized using several techniques (SEM imaging, BET, GC, ICP and FTIR). The properties of BC were found to be defined both by the feedstock and the production process. The BC were then applied to the AD of the organic fraction of municipal solid waste (OFMSW) using three doses (1, 5% and 10% w/w TS). Compared to the control, there was an increase in methane production in BC3 at doses 1% and 5% (+15 and +30%, respectively) and a decrease in BC1 and BC2 at 1% (−33% and −19%, respectively). The decrease in biogas production was often paired with an increased methane content. A two-way ANOVA analysis showed that the interaction of biochar dose and type had a significant effect on methane yield, meaning that the effect of BC on AD cannot be predicted with the dose or the type alone. When a second substrate feeding was performed, no significant differences on methane production were observed among the experimental conditions. Key aspects to properly assess the economic viability of the process have been also discussed. Further experiments could help to fill knowledge gaps and clarify the roles of BC characteristics and dose on AD performance.","PeriodicalId":510140,"journal":{"name":"Frontiers in Chemical Engineering","volume":"231 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140751054","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}

{"title":"Influence of type of aluminium stearate on triboelectrification of dry-coated surfaces of functionalised glass beads","authors":"W. Goh, Jiachen Guo, Xiaodong Jia, M. Ghadiri","doi":"10.3389/fceng.2024.1347342","DOIUrl":"https://doi.org/10.3389/fceng.2024.1347342","url":null,"abstract":"Triboelectrification of powders and grains is deleterious in a large number of manufacturing operations, due to its adverse effect on process consistency and reliability. To mitigate it, charge neutralisers are commonly employed. However, their selection is often based on trial and error. This study is conducted to systematically examine the influence of the ionic polarity strength of a charge neutraliser, specifically aluminium stearate (AlSt), on charge transfer. AlSt has three types with different numbers of stearate chains, thereby influencing the electron exchange propensity of the molecule. The experiments involved surface-treated glass beads in the sieve size range of 90–150 µm (to make them hydrophilic by acid washing or hydrophobic by silanisation), then coated with the three forms of AlSt (mono-, di- and tri-) for charge mitigation. These coated beads were subjected to aerodynamic dispersion to cause triboelectrification, in order to quantitatively evaluate their charge neutralising effect. The experiments were conducted with four contact surfaces: stainless steel, copper, aluminium, and polytetrafluoroethylene (PTFE). Both acid-washed and silanised glass beads exhibited negative charging against aluminium, copper and stainless steel (typically around 22–44 nC/g), but positive charging against PTFE (around 90 nC/g and 19 nC/g for acid-washed and silanised, respectively), despite having significantly different surface functional groups. A complex trend is observed for the effect of the amount of AlSt present on the surfaces, the type of AlSt and the surface treatment. A relatively good charge reduction behaviour was seen for AlSt-coated acid washed glass beads, but for silanised glass beads, AlSt coating actually increases their charge level.","PeriodicalId":510140,"journal":{"name":"Frontiers in Chemical Engineering","volume":"55 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140085592","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}

{"title":"CFD-DEM model of a cold plasma assisted fluidized bed powder coating process","authors":"P. Martin-Salvador, R. H. Verschueren, T. De Beer, A. Kumar","doi":"10.3389/fceng.2024.1347313","DOIUrl":"https://doi.org/10.3389/fceng.2024.1347313","url":null,"abstract":"Cold plasma coating technology for surface functionalization of pharmaceutical powder particles is a promising approach to introduce new characteristics such as controlled release layers, improved powder flow properties, stability coatings, and binding of active components to the surface. This is typically achieved in a fluidized bed reactor, where a jet containing the chemical precursor and the plasma afterglow is introduced through a nozzle while extra fluidization gas is injected from the bottom plate. However, the process requires proper mixing of the particles and precursor inside the plasma active zone to ensure a homogeneous coating of all particles. Therefore, such coating processes are challenging to optimize, given the complex phenomena involved in fluidization, plasma species reactions, and surface reactions. In this study, we use the CFD-DEM approach as implemented in the CFDEM®coupling package to model the process. The functionalization rate is modeled as mass transfer from the surrounding gas onto the particles, using a plasma coating zone where this transfer may happen. Mass transfer is switched off outside this zone. The DEM contact parameters and drag force are calibrated to our cellulose beads model powder using experimental tests composed by the FT4 rheometer and spouting tests. We show that while the chemistry can make or break the process, the equipment design and process conditions have a non-negligible effect on the coating metrics and thus must be considered. Cases where the fluidization flow is not high enough to produce good mixing have a high coefficient of variation of the coating mass, and therefore, they must be avoided. In addition, we also proposed an extrapolation procedure to provide results at longer coating times, showing that it is possible to predict coating performance even when simulations of the process for more than a minute are not computationally efficient.","PeriodicalId":510140,"journal":{"name":"Frontiers in Chemical Engineering","volume":"36 30","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140426114","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}

{"title":"Transition metal oxide nanocatalysts for the deoxygenation of palm oil to green diesel","authors":"C. E. Guerrero-Corona, J. A. Melo-Banda, M. Lam-Maldonado, L. A. Vega-Ibarra, N. Díaz-Zavala, M. A. Meraz-Melo","doi":"10.3389/fceng.2024.1334355","DOIUrl":"https://doi.org/10.3389/fceng.2024.1334355","url":null,"abstract":"This study investigated the hydrodeoxygenation of palm oil by different oxide nanocatalysts of transition metals α -Fe2O3, NiO, and NiFe2O4, which were synthesized by hot injection. All nanomaterials were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, and dynamic light dispersion. The catalytic evaluation was performed in a Parr-type reactor at 350°C, 3.5 MPa of H2 pressure, and 3 h of reaction. The liquid product obtained was analyzed by ultraviolet-visible light spectroscopy to identify the n-C16 generated during the reaction. The activity in the deoxygenation of fatty acids to produce n-C16 hydrocarbons has the following order: α-Fe2O3 < NiFe2O4 < NiO.","PeriodicalId":510140,"journal":{"name":"Frontiers in Chemical Engineering","volume":"70 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140439196","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}

{"title":"Removal of heavy metals from wastewater using reverse osmosis","authors":"Vercus Lumami Kapepula, Patricia Luis","doi":"10.3389/fceng.2024.1334816","DOIUrl":"https://doi.org/10.3389/fceng.2024.1334816","url":null,"abstract":"This study presents an overview of and innovations in reverse osmosis (RO) membrane processes for rejecting charged metal ions in wastewater in relation to the main problems associated with purification methods. It also explains the emergence of nanomaterials and the different methods applied for RO membrane modification to improve performance. Membrane regeneration and retentate management are also considered. The study concludes with an economic feasibility study for the industrial scale-up of the methodology.","PeriodicalId":510140,"journal":{"name":"Frontiers in Chemical Engineering","volume":"313 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140447258","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}

{"title":"Predictive functional control for separation processes by liquid-liquid extraction","authors":"V. Vanel, J. Mallet, B. Dinh, S. Michaud, M. Montuir, F. Vilpini","doi":"10.3389/fceng.2023.1294784","DOIUrl":"https://doi.org/10.3389/fceng.2023.1294784","url":null,"abstract":"A separation process by liquid-liquid extraction is a well-known and widespread industrial technology implemented to quantitatively recover valuable chemical elements. In the nuclear industry, such processes have been used for decades to recover uranium and plutonium from spent fuel. The process is non-linear and time constants vary over a wide range. Former studies on a simplified model showed linear controllers such as PID were not adapted to regulate these separation processes. The objective of this study is to propose process monitoring by using available physical models within the PAREX code and to validate the feasibility to monitor a separation process by using directly the PAREX code as a black box. The Predictive Functional Control (PFC) command law manages to monitor non-linear separation processes by liquid-liquid extraction, when using an existing physical model implemented in the PAREX code. An online alignment of the model on process values is necessary to keep the model sufficiently representative to predict the future behaviour of the process. As a reference benchmark, the PID control loop is also simulated with the physical model. The PFC and PID regulations are compared to evaluate the gain of using physical models implemented in the PAREX code. A simulation tool has been developed to implement the PID and Predictive Functional Control (PFC) controllers for separation processes by liquid-liquid extraction. The PFC command law manages to monitor non-linear separation processes, when using a physical model connected to the PAREX code. Even if the PID controller may be locally more efficient, the great strength of the PFC controller is to enable good performances on wider operating conditions, with an easier parametrization. The PFC algorithm is a mean to deal with the process characteristic features, like non-linearity and time constant change. The PFC controller appears to be a good candidate for experimental tests. A mid-term objective is to include the state estimator tool in the control loop to consolidate the controlled variable measurements. These developments may be regarded as an add-on module in a digital factory concept. Results shown in this article are only from simulation. For the sake of data confidentiality, studies with the PAREX code cannot be published and numerical parameters of the process are normalized. These simulations will be validated during further experimental tests.","PeriodicalId":510140,"journal":{"name":"Frontiers in Chemical Engineering","volume":"48 30","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139775598","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}