Chemical Engineering Science: X最新文献

{"title":"Impact of solvent properties on post-combustion carbon capture processes: A vapor–liquid equilibrium modelling approach","authors":"He Jin,&nbsp;Pei Liu,&nbsp;Zheng Li","doi":"10.1016/j.cesx.2021.100095","DOIUrl":"10.1016/j.cesx.2021.100095","url":null,"abstract":"<div><p>This paper deals with the effect of solvent vapor liquid equilibrium (VLE) properties on the heat duty in a post-combustion CO₂ capture process. The conceptual solvent properties include the absorption heat, absorption performance and cyclic capacity, modeled by a three-parameter VLE equation. There are four processes considered. A conventional process serves as a reference case. An ideal process is used to study the energy saving potential. As typical process improvements, an intercooling and a rich split process are used to analyze the heat duty reduction effect. The optimal solvent in each process is obtained by minimizing the total heat duty. By the sensitive analysis, the solvent with less favorable VLE properties owns a larger energy saving potential and energy saving effect. Results show that the rich split is a more energy-efficient process improvement method than the intercooling configuration for the typical amine solvents.</p></div>","PeriodicalId":37148,"journal":{"name":"Chemical Engineering Science: X","volume":"10 ","pages":"Article 100095"},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cesx.2021.100095","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"111922665","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In-situ observation of water evaporation in exhaust gas catalyst via sub-micron and sub-second X-ray tomography","authors":"Salvatore De Angelis ,&nbsp;Hai P. Nguyen ,&nbsp;Satoshi Nagao ,&nbsp;Keisuke Kishita ,&nbsp;Federica Marone ,&nbsp;Felix N. Büchi","doi":"10.1016/j.cesx.2021.100091","DOIUrl":"10.1016/j.cesx.2021.100091","url":null,"abstract":"<div><p>Condensation of liquid water in the porous washcoat layer of exhaust gas catalysts limits their conversion efficiency during the cold-start of an internal combustion engine (ICE). The evaporation kinetics also determine the functionality of the catalyst. In this work, we study water evaporation in the washcoat layers using in-situ X-ray tomographic microscopy with high temporal and spatial resolution. A novel in-situ heating setup is developed, able to reproduce real-world conditions in terms of temperature and gas speed. It is demonstrated that with a voxel size of 0.4 μm, satisfactory data quality can be achieved with a total acquisition time for tomographic volumes of 0.5 s. Thanks to the high temporal and spatial resolution, the water evaporation in a Al₂O₃ washcoat layer can be described under representative conditions. We find that the time evolution of the evaporation follows an exponential-like behavior and water starts to evaporate from the macroscopic washcoat cracks.</p></div>","PeriodicalId":37148,"journal":{"name":"Chemical Engineering Science: X","volume":"10 ","pages":"Article 100091"},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cesx.2021.100091","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41573626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A world-renowned scientist of coal conversion and clean energy","authors":"Norman N. Li","doi":"10.1016/j.cesx.2021.100093","DOIUrl":"10.1016/j.cesx.2021.100093","url":null,"abstract":"","PeriodicalId":37148,"journal":{"name":"Chemical Engineering Science: X","volume":"10 ","pages":"Article 100093"},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cesx.2021.100093","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"102354871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Kinetics behavior of Co/Ni-ordered mesoporous alumina for the CO methanation","authors":"Yong-Shan Xiao ,&nbsp;Yong-Hong Song ,&nbsp;Qun-Xing Luo ,&nbsp;Xian-Ying Shi ,&nbsp;Jiageng Li ,&nbsp;Qing-Qing Hao ,&nbsp;Zhao-Tie Liu ,&nbsp;Zhong-Wen Liu","doi":"10.1016/j.cesx.2021.100094","DOIUrl":"10.1016/j.cesx.2021.100094","url":null,"abstract":"<div><p>The severe requirement of a higher activity at lower temperatures and a longer stability at higher temperatures evokes a great challenge for the development of an industrially viable catalyst for the CO methanation reaction. In this work, the Co-Ni bimetallic catalysts were synthesized via post-impregnating the cobalt precursor within the mesoporous channel of Ni-embedded ordered mesoporous alumina (Ni-OMA). The low-temperature activity and high-temperature stability of Co/Ni-OMA for the CO methanation were significantly regulated by easily tuning the ratio of free Co and confined Ni species. The optimal catalyst of 8Co/15Ni-OMA showed a high activity with the CH₄ formation rate of 126 mol kg_cat⁻¹ h⁻¹ at a temperature of as low as 300 °C and a long-term durability for a time-on-stream of 200 h without an observable deactivation under the conditions of 600 °C and an extremely high GHSV of 180000 mL g⁻¹ h⁻¹. Kinetics results reveal that the apparent activation energy of the CO methanation over 8Co/15Ni-OMA (100.2 kJ mol⁻¹) was clearly lower than that over 15Ni-OMA (124.0 kJ mol⁻¹) or 15Co-OMA (131.8 kJ mol⁻¹). In the absence of mass transport and heat transfer limitations, three microkinetics models were developed following the H-assisted CO dissociation and Langmuir-Hinshelwood mechanism, which the H-assisted CO dissociation, the hydrogenation of surface carbon species (C*) or surface CH₃* species are proposed as the rate-determining step, respectively. The kinetics behaviors over 15Ni-OMA and 8Co/15Ni-OMA are matched well with all of the kinetics models, indicating the same elementary sequence and rate-determining step. In the case of 15Co/OMA, the CH₄ formation rate was predicted very well by the kinetics models derived from the stepwise hydrogenation of surface carbon species as the rate-determining step, and the kinetics model based on the H-assisted CO dissociation as the rate-determining step could be ruled out, indicating that the rate for the H-assisted CO dissociation rate is faster than that of the following stepwise hydrogenation. Based on the discrimination of different kinetics models, Ni species confined within OMA matrix were proposed as the dominant active sites for catalyzing the CO methanation, while the post-impregnated Co was acted as a promoter for the H-assisted CO dissociation. As a result, an enhanced low-temperature activity was achieved over the optimal 8Co/15Ni-OMA catalyst.</p></div>","PeriodicalId":37148,"journal":{"name":"Chemical Engineering Science: X","volume":"10 ","pages":"Article 100094"},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cesx.2021.100094","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"93173488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Addition of potassium iodide reduces oxidative degradation of monoethanolamine (MEA)","authors":"Vanja Buvik,&nbsp;Ricardo R. Wanderley,&nbsp;Hanna K. Knuutila","doi":"10.1016/j.cesx.2021.100096","DOIUrl":"10.1016/j.cesx.2021.100096","url":null,"abstract":"<div><p>We introduce the addition of stable salts to aqueous MEA as a way of inhibiting oxidative degradation reactions. We performed oxidative degradation studies in aqueous MEA containing sodium chloride (NaCl) and potassium iodide (KI). These “salted amine solvents” have been shortened to SAS. The 2.0 %wt. and 1.0 %wt. KI SAS show remarkable oxidative degradation behavior. Loss of alkalinity after 42 days of oxidative degradation experiments with the 1.0 %wt. KI SAS was of 4%, whereas that of aqueous MEA was of 40% after only 21 days. We evaluated how the addition of stable salts impacts CO₂ solubility, viscosity, and thermal degradation and corrosion behavior and verify negligible deviations from aqueous MEA. Thus, addition of stable salts affects oxidative degradation phenomena without deranging CO₂ solubility or mass transfer rates. With the promising inhibition behavior of KI on MEA degradation, this work presents the initial steps towards making it a commercially viable degradation inhibitor.</p></div>","PeriodicalId":37148,"journal":{"name":"Chemical Engineering Science: X","volume":"10 ","pages":"Article 100096"},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cesx.2021.100096","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"112191786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Scale-up of micro- and milli-reactors: An overview of strategies, design principles and applications","authors":"Zhengya Dong ,&nbsp;Zhenghui Wen ,&nbsp;Fang Zhao ,&nbsp;Simon Kuhn ,&nbsp;Timothy Noël","doi":"10.1016/j.cesx.2021.100097","DOIUrl":"10.1016/j.cesx.2021.100097","url":null,"abstract":"<div><p>Continuous-flow microreactor technology has been embraced by researchers in academia and industry due to its excellent transport properties and the increased safety and control over challenging chemical transformations. Despite its popularity, scaling the benefits associated with the microenvironment has proven to be a daunting challenge. This review provides an up-to-date overview concerning the different scale-up approaches of micro/milli-reactors, including numbering up (both internal and external), sizing up (increasing length, geometry similarity and constant pressure drop strategies) and a combination of numbering up and sizing up. The strategies, design principles and applications of each approach have been discussed in detail. Each scale-up approach has its merits and limitations. However, scale-up factors, that are required in the fine chemical and pharmaceutical industry, are within reach when different scale-up approaches are combined.</p></div>","PeriodicalId":37148,"journal":{"name":"Chemical Engineering Science: X","volume":"10 ","pages":"Article 100097"},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cesx.2021.100097","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"97451763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Breakthrough and innovative clean and efficient coal conversion technology from a chemical engineering perspective","authors":"Ke-Chang Xie","doi":"10.1016/j.cesx.2021.100092","DOIUrl":"10.1016/j.cesx.2021.100092","url":null,"abstract":"<div><p>To adapt to the needs of a developing global society and provide water and ecological environmental protection, it is necessary to enhance technological innovations for clean coal conversion to achieve the basic requirements of “clean and low carbon, safe and efficient”. This paper puts forward a new idea of the chemical conversion of coal in terms of the material conversion efficiency and energy utilization efficiency of common key technologies, forward leading technologies, modern engineering technologies, and disruptive technologies. In addition, it is pointed out that there are many chemistry and chemical engineering problems restricting the innovation and breakthrough of new clean coal technologies. In view of this problem, we carry out an in-depth study of the main processes used in the coal chemical industry, and find that understanding the structure–activity relationship, designing ideal catalysts, strengthening the main reaction processes, and promoting the integration of processes used in other chemical fields into the coal chemical industry are helpful for realizing the steady development of the modern coal chemical industry. Such approaches can lead to improved economic benefits, and provide means for realizing the clean and efficient transformation of coal.</p></div>","PeriodicalId":37148,"journal":{"name":"Chemical Engineering Science: X","volume":"10 ","pages":"Article 100092"},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cesx.2021.100092","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"94760649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel evaluation method to determine the local mixing time distribution in stirred tank reactors","authors":"J. Fitschen ,&nbsp;S. Hofmann ,&nbsp;J. Wutz ,&nbsp;A.v. Kameke ,&nbsp;M. Hoffmann ,&nbsp;T. Wucherpfennig ,&nbsp;M. Schlüter","doi":"10.1016/j.cesx.2021.100098","DOIUrl":"10.1016/j.cesx.2021.100098","url":null,"abstract":"<div><p>Stirred tank reactors are frequently used for mixing as well as heat- and mass transfer processes in chemical and biochemical engineering due to their robust operation and extensive experiences in the past. However, for cell culture processes like mammalian cell expression systems, special requirements have to be met to ensure optimal cell growth and product quality. One of the most important requirements to ensure ideal transport processes is a proper mixing performance, characterized typically by the global mixing time <span><math><mrow><msub><mrow><mi>t</mi></mrow><mrow><mi>mix</mi><mo>,</mo><mi>global</mi></mrow></msub></mrow></math></span> or the dimensionless global mixing time <span><math><mrow><msub><mrow><mi>t</mi></mrow><mrow><mi>mix</mi><mo>,</mo><mi>global</mi></mrow></msub><mo>·</mo><mi>n</mi></mrow></math></span>. As an evaluation method for mixing time determination, the time is usually determined until a tracer signal (e.g. conductivity) has reached a constant value after a peak has been introduced (e.g. by adding a salt). A disadvantage of this method is, that the position of tracer feeding as well as the position of the probe significantly influences the detected mixing time. Further on, the global mixing time does not provide any information about the spatial and temporal ”history” of the mixing process to identify areas that are mixed poorly or areas that form stable compartments. To overcome this disadvantage, a novel image analysis will be presented in this study for the detailed characterization of mixing processes by taking into account the history of mixing. The method is based on the experimental determination of the local mixing time distribution by using a multi-color change caused by a pH-change in a bromothymol blue solution. A 3<!--> <!-->L transparent stirred tank reactor is used for the benchmark experiment. To demonstrate the suitability of the new characterization method for the validation of numerical simulations, a calculation with a commercial Lattice-Boltzmann approach (<em>M-Star CFD</em>) has been performed additionally and evaluated regarding mixing time distributions. The exemplary application of image analysis to a numerical mixing time simulation shows good agreement with the corresponding experiment. On the one hand, this shows that the method can also be interesting for numerical work, especially for experimental validation, and on the other hand, this allows much deeper insights into the mixing behavior compared to conventional mixing criteria. For example the new method enables the characterization of mixing on different scales as well as the identification of micro- and macroscopic flow structures. The strong influence of the acid to base ratio on mixing time experiments becomes clearly visible with the new method.</p></div>","PeriodicalId":37148,"journal":{"name":"Chemical Engineering Science: X","volume":"10 ","pages":"Article 100098"},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cesx.2021.100098","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46721228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sustainable energy corps: Building a global collaboration to accelerate transition to a low carbon world","authors":"Monty Alger,&nbsp;Darrell Velegol,&nbsp;Rui Shi","doi":"10.1016/j.cesx.2021.100099","DOIUrl":"10.1016/j.cesx.2021.100099","url":null,"abstract":"<div><p>Climate change is a critical 21st century challenge. Major initiatives are underway across the globe but the key metric of success the reduction of greenhouse gas concentration (GHG) in the atmosphere is not improving. A new model for engaging, educating, and securing support from the world community is needed. We propose the formation of a new Sustainable Energy Corps, designed to engage students, communities, professionals, universities, companies, government, and other stakeholders. The focus is on measurement and reduction of GHG concentration in the atmosphere. Translating the “adopt-a-highway” model the world would be divided into local regions connected globally using contemporary data and content platforms. A proposed approach for building a global integrated approach is presented.</p></div>","PeriodicalId":37148,"journal":{"name":"Chemical Engineering Science: X","volume":"10 ","pages":"Article 100099"},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cesx.2021.100099","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"103841254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assembly-reassembly of coal fly ash into Cu-SSZ-13 zeolite for NH3-SCR of NO via interzeolite transformations","authors":"Bing Wang ,&nbsp;Lingjun Ma ,&nbsp;Lina Han ,&nbsp;Yu Feng ,&nbsp;Jiangliang Hu ,&nbsp;Wei Xie ,&nbsp;Weiren Bao ,&nbsp;Liping Chang ,&nbsp;Zhanggen Huang ,&nbsp;Jiancheng Wang","doi":"10.1016/j.cesx.2021.100089","DOIUrl":"10.1016/j.cesx.2021.100089","url":null,"abstract":"<div><p>Coal fly ash (CFA) solid residues can be destructive and cause severe pollution. Here, we report an interzeolite transformations strategy named the “assembly-reassembly” method to convert the CFA into Cu-SSZ-13 zeolite. It is a useful catalyst for NH₃ mediated selective catalytic reduction (NH₃-SCR) of NO. The raw CFA can be converted to ANA or FAU primary zeolite by an “assembly” step and CHA resultant zeolite by the subsequent “reassembly” step in the hydrothermal alkaline solution. We focus on the mechanism of the CFA-to-CHA process and the NH₃-SCR performance of the Cu-SSZ-13 zeolite. The synthesized Cu-SSZ-13 possesses a standard CHA-type framework structure and controllable Al placement. It shows a high NO conversion rate that is comparable to the commercial Cu-SSZ-13. This approach enables the facile transformation of raw CFA waste to Cu-SSZ-13 zeolite with desirable composition and catalytic property, which provides insights into the formation mechanism during the interzeolite transformations process.</p></div>","PeriodicalId":37148,"journal":{"name":"Chemical Engineering Science: X","volume":"10 ","pages":"Article 100089"},"PeriodicalIF":0.0,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.cesx.2021.100089","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"97754676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}