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Enhancing the lubricity of gas-to-liquid (GTL) paraffinic kerosene: impact of the additives on the physicochemical properties

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BMC chemical engineering 2020年第1期2卷 1-16页

作者： Hani Ababneh Nasr Mohammad Hanif A. Choudhury Nimir Elbashir Lei Zhang Rafiqul Gani Gordon McKay Chemical Engineering Department College of Engineering Qatar University 2713 Doha Qatar Petroleum Engineering Program Texas A&M University at Qatar P.O. Box 23874 Doha Qatar Institute of Chemical Process Systems Engineering School of Chemical Engineering Dalian University of Technology Dalian 116024 China PSE for SPEED Skyttemosen 6 DK_3450 Allerod Denmark Sustainable Energy Program Division of Sustainable Development College of Science and Engineering Hamad Bin Khalifah University P.O 5825 Doha Qatar

Synthetic paraffinic kerosene (SPK) is an ultra-clean fuel with low aromatic content and negligible quantities of sulfur compounds. Although, SPK has a good potential to replace the conventional fuel Jet A-1, it also has some deficiencies. One of them is the low lubricity compared to its conventional counterpart Jet A-1. To improve the lubricity of SPK, three selected additives have been mixed with SPK at different concentrations. The lubricity of the samples was determined experimentally and the samples that meet the industry specifications have been studied further. The effect of the additives on the physicochemical properties, such as, density, flash point, freezing point, viscosity, and heat content, were investigated. Linoleic acid was found to be an excellent lubricity improver even at a very low concentration and its negative impact on the other physicochemical properties was found to be insignificant. Ethyl oleate also demonstrated significant improvement in lubricity at low concentrations but had a negative impact on the fuel’s freezing point at high concentrations. Quinoline, at high concentrations, elevated the blend’s freezing point above the acceptable limits. In parallel to the experimental campaign, a pre-existing mathematical modelling tool was utilized to predict the properties of interest. The lubricity model was successfully introduced into the mathematical model in order to improve the capabilities of the model. Linoleic acid sample showed the best improvement in lubricity of SPK with wear scar diameter of 417 μm; well below the ASTM D7566 maximum limit of 850 μm. The dual nature of this study facilitated the optimization of the physicochemical properties of the fuel samples.

关键词： Synthetic paraffinic kerosene Lubricity Jet A-1 Physicochemical properties Properties modelling

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Dynamics of a distillation column with distributed and conventional approach using multivariable control with adjustment based on multiple errors

Dynamics of a distillation column with distributed and conve...

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International Conference on Communications, Computing and Control Applications (CCCA)

作者： Cintia Marangoni Joel G. Teleken Iaçanã G. B. Parisotto Leandro O. Werle Ariovaldo Bolzan Ricardo A. F. Machado University of Joinville Region - Univille Process Engineering Master's Program Joinville SC Brazil UFSC Chemical Engineering Department Federal University of Santa Catarina Florianópolis SC Brazil

In this study, an application of a multivariable conventional control structure of the continuous tray distillation columns is compared to a new distributed proposal. This was done considering the process dynamics, more specifically the transition time when the process is disturbed. As the conventional approach, the top and bottom product temperatures of the distillation column were selected as controlled variables and the reflux ratio and reboiler heat supply as manipulated variables. These loops plus an intermediate temperature column stage controlled using the heat supply of one tray as the manipulated variable comprised the distributed control structure. The regulator problem was considered for the experimental control studies. Feed temperature was chosen as the load variable. It is important to notice that this study focuses on the response process and does not address the development or design of the control structure. The main aim is to compare the time response of the process when subject to an expected disturbance using two different approaches (conventional and distributed). Experiments were carried out with multivariable PI controllers and the multiple errors (desired controller variable and the corresponding measured output) of each controlled variable were used together to computed the control actions (interactions were considered). Better performance in relation to transition time was observed with the distributed approach, indicating that this is an interesting strategy which could be used to minimize the transients in a distillation column.

关键词： Heating Feeds Proposals Distillation equipment process control Temperature sensors

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Robust parameter estimation in a model for glucose kinetics in type 1 diabetes subjects

Robust parameter estimation in a model for glucose kinetics ...

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28th Annual International Conference of the IEEE engineering in Medicine and Biology Society, EMBS'06

作者： Paterm, Cesar C. Rodríguez-Fernández, María Bevier, Wendy C. Zisser, Howard Banga, Julio R. Jovanovič, Lois Doyle III, Francis J. IEEE Department of Chemical Engineering University of California Santa Barbara Santa Barbara CA 93106-5080 Biomolecular Science and Engineering Program University of California Santa Barbara Santa Barbara CA 93106-9611 Sansum Diabetes Research Institute 2219 Bath St. Santa Barbara CA 93105 Process Engineering Group IIM-CSIC Spanish Council for Scientific Research c/Eduardo Cabello 6 36208 Vigo Spain

ISBN: (纸本)1424400325

There is a significant push to develop closed-loop control systems to deliver insulin for type 1 diabetic subjects. As part of this process, mathematical models are required to test and validate the proposed algorithms. There are several published physiology-based models of glucose and insulin dynamics in the literature, however, all of them were derived using data from subjects without diabetes. For this particular study we have selected one of the recently published models, by Hovorka et al. [1], replacing the subcutaneous insulin infusion model with the one described by Wilinska et al. [2]. Five subjects with type 1 diabetes underwent a hyperinsulinemic-euglycemic clamp with a meal challenge and corresponding subcutaneous insulin bolus. The data collected were used to fit the model parameters using global optimization methods. Our results show that the model is capable of describing the observed dynamics for type 1 subjects under the experimental conditions, and as such can be used to simulate subject behavior under the experimental conditions. ©2006 IEEE.

关键词： Glucose

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Systematic design of separation process for bioethanol production from corn stover

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BMC chemical engineering 2020年第1期2卷 1-16页

作者： Amornraksa, Suksun Subsaipin, Ittipat Simasatitkul, Lida Assabumrungrat, Suttichai Chemical and Process Engineering Program The Sirindhorn International Thai-German Graduate School of Engineering (TGGS) King Mongkut’s University of Technology North Bangkok Bangkok Thailand Department of Industrial Chemistry Faculty of Applied Science King Mongkut’s University of Technology North Bangkok Bangkok Thailand Center of Excellence in Catalysis and Catalytic Reaction Engineering Department of Chemical Engineering Faculty of Engineering Chulalongkorn University Bangkok Thailand

Separation process is very crucial in bioethanol production as it consumes the highest energy in the process. Unlike other works, this research systematically designed a suitable separation process for bioethanol production from corn stover by using thermodynamic insight. Two separation processes, i.e., extractive distillation (case 2) and pervaporation (case 3), were developed and compared with conventional molecular sieve (case 1). process design and simulation were done by using Aspen Plus program. The process evaluation was done not only in terms of energy consumption and process economics but also in terms of environmental impacts. It was revealed that pervaporation is the best process in all aspects. Its energy consumption and carbon footprint are 60.8 and 68.34% lower than case 1, respectively. Its capital and production costs are also the lowest, 37.0 and 9.88% lower than case 1.

关键词： Bioethanol Corn stover process design Economic analysis Life cycle analysis

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Development of Bacterial Cellulose Membranes Incorporated with Plant Extracts

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Macromolecular Symposia 2022年第1期406卷 2200031-2200031页

作者： Neves, Eduarda Zeni Kumineck Junior, Sandro Rogério Katrucha, Graziéli Paulino Silveira, Victória Fonseca Silveira, Márcia Luciane Lange Pezzin, Ana Paula Testa Schneider, Andréa Lima dos Santos Garcia, Michele Cristina Formolo Apati, Giannini Pasiznick Department of Chemical Engineering University of the Joinville Region – UNIVILLE SC Joinville89219-710 Brazil Postgraduate Program in Process Engineering University of the Joinville Region – UNIVILLE SC Joinville89219-710 Brazil Postgraduate Program in Environment and Health University of the Joinville Region – UNIVILLE SC Joinville89219-710 Brazil

A new generation of functional healing membranes has been researched to avoid infection and improve wound healing, combining wound moisture maintenance properties, exudate removal, antimicrobial activity, and the absence of side effects. Thus, this work aims to synthesize wound dressing membranes of bacterial cellulose (BC) incorporated with different plant extracts with antimicrobial properties. The BC membranes are synthesized by the bacterium Komagataeibacter hansenii and are associated with the extracts through the ex situ incorporation technique. The barbatimão extract presents the most significant total phenolic content and antimicrobial activity of the extracts researched. The determination of tannins and flavonoids confirms the extracts’ incorporation into the samples’ structure. The thermogravimetric analysis of the membranes incorporated with the extracts shows a reduction in the thermal stability relative to BC. The results show a good final extract for developing healing membranes with antimicrobial properties. © 2022 Wiley-VCH GmbH.

关键词： Membranes

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Synthesis of Self-triggered Receding Horizon Controllers:A Relaxed Dynamic programming Approach

Synthesis of Self-triggered Receding Horizon Controllers:A R...

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第三十四届中国控制会议

作者： Liang Lu Jay H.Lee Department of Chemical and Biomolecular Engineering (BK21 Plus Program) Korea Advanced Institute of Science and Technology State Key Laboratory of Synthetical Automation for Process Industries Northeastern University

This paper presents a self-triggered MPC controller design strategy for constrained linear systems. Based on the socalled relaxed dynamic programming inequality, the synthesis procedure allows us to determine both the updated MPC control action and the next triggering time. The resulting self-triggered MPC control law preserves stability and constraint satisfaction and also satisfy certain a priori chosen performance requirements. An illustrative example shows the effectiveness of this selftriggered MPC implementation.

关键词： Self-triggered Control,Model Predictive Control,Relaxed Dynamic programming

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Synthesis of PMMA Nanoparticles Loaded with Geopropolis Extract from the Brazilian Stingless Bee Melipona quadrifasciata Lepeletier, 1836 by Miniemulsion Polymerization

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Macromolecular Symposia 2022年第1期406卷 2200046-2200046页

作者： da Silva, Thiago S. Nogueira, André L. Lafratta, Fernando H. Department of Chemical and Food Engineering Federal University of Santa Catarina – UFSC Florianópolis88040-900 Brazil Department of Chemical Engineering and Post-Graduation Program in Process Engineering University of the Region of Joinville – UNIVILLE Santa Catarina Joinville89219-710 Brazil Department of Mechanical Engineering Santa Catarina State University – UDESC Santa Catarina Joinville89219-710 Brazil

The present work aims to encapsulate the concentrated geopropolis extract from the Brazilian stingless bee Melipona quadrifasciata quadrifasciata Lepeletier, 1836 in poly(methyl methacrylate) (PMMA) nanoparticles produced by miniemulsion polymerization. The concentrated geopropolis extract is obtained by hydroalcoholic maceration and characterized by ultraviolet–visible spectrophotometry (UV–Vis) to quantify flavonoids and polyphenols in terms of quercetin (Q) and galic acid (GA), respectively. The PMMA-Propolis nanoparticles is characterized by size exclusion chromatography (SEC), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), UV–Vis and nuclear magnetic resonance (NMR1H). UV–Vis results of the geopropolis extract revealed an average flavonoid content of 22.51 mg Q g–1 and an average polyphenol content of 10.15 mg GA g–1. TEM images showed that the produced PMMA nanoparticles are spherical, and their average diameter reduced from 72.62 to 44.60 nm by increasing the propolis concentration from 0% to 40%. Additionally, the kinetic data reveal a reduction of the polymerization reaction rate as well as the average molecular weight when raising the propolis extract concentration in the reaction media. These results suggest that propolis extract may be used as a biocompatible and biodegradable co-stabilizer and chain transfer agent in miniemulsion polymerization reactions of vinyl monomers. © 2022 Wiley-VCH GmbH.

关键词： Thermogravimetric analysis

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Green synthesis of iron oxide nanoparticles using Cymbopogon citratus extract and sodium carbonate salt: Nanotoxicological considerations for potential environmental applications

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Environmental Nanotechnology, Monitoring and Management 2020年 14卷

作者： Patiño-Ruiz, David Sánchez-Botero, Lina Tejeda-Benitez, Lesly Hinestroza, Juan Herrera, Adriana Engineering Doctorate Program Nanomaterials and Computer-Aided Process Engineering Research Group Universidad de Cartagena Cartagena 130010 Colombia Department of Fiber Science and Apparel Design Cornell University Ithaca United States Chemical Engineering Program Nanomaterials and Computer-Aided Process Engineering Research Group Universidad de Cartagena Cartagena 130010 Colombia

Synthesis of functional and biocompatible nanomaterials, based on the green chemistry paradigm, aims to innovate by using environmentally friendly techniques. Green synthesis using natural extracts instead of chemicals is proving to be an efficient route to prepare metal and metal oxide nanoparticles. In this study, the green synthesis of iron oxide nanoparticles (FeO-NPs) is reported, using a Cymbopogon citratus (C. citratus) extract and sodium carbonate as the reducing and pH stabilizer agents, respectively. FeO-NPs are extensively studied and applied due to the exceptional physicochemical properties, outstanding the superparamagnetism, and the large surface area. These properties are corroborated using different characterization techniques, in which a regular crystal structure and the magnetic response are similar compared with FeO-NPs synthesized via the traditional methods. The presence of magnetite and maghemite (Fe₃O₄ and γ-Fe₂O₃) phases are evidenced. A major composition of Fe₃O₄ allows predominant superparamagnetism. However, surface functionalization reduces the spin coordination avoiding a high saturation magnetization. The presence of phytochemical content in the C. citratus allows the reduction of iron(III) to iron(II) using H⁺ radicals produced from hydroxyl and carbonyl groups, and the in-situ functionalization using these groups. Additionally, the biocompatibility of the FeO-NPs is evaluated performing a nanotoxicological assessment, in which Caenorhabditis elegans nematodes are used as the biological model. The presence of organic molecules on FeO-NPs promotes no toxicity and low effects on the locomotion, growth, and reproduction, suggesting a low risk using these functional nanoparticles for environmental applications, and outstanding the synthesis route with a green approach. © 2020 Elsevier B.V.

关键词： Caenorhabditis elegans Cymbopogon citratus extract Ecotoxicological effects FeO nanoparticles Green synthesis Sodium carbonate

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Bacterial Cellulose Membranes Incorporated with Lipase for Oil Degradation

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Macromolecular Symposia 2024年第6期413卷

作者： Silveira, Victória Fonseca da Silva, Victória Mendes Junior, Sandro Rogério Kumineck Garcia, Michele Cristina Formolo Pezzin, Ana Paula Testa de Oliveira, Therezinha Maria Novais Schneider, Andrea Lima dos Santos Postgraduate Program in Health and Environment University of Joinville Region – UNIVILLE Santa Catarina Joinville89219-710 Brazil Department of Chemical Engineering University of Joinville Region – UNIVILLE Santa Catarina Joinville89219-710 Brazil Postgraduate Program in Process Engineering University of Joinville Region – UNIVILLE Santa Catarina Joinville89219-710 Brazil

The immobilization of enzymes increases their stability and allows their reuse, and bacterial cellulose (BC) is a material that can be used in this technique. This work aims to produce an enzymatic product to degrade oils and fats using BC as a matrix. Komagataeibacter hansenii bacteria produce BC membranes, and lipase is immobilized on the membranes by ex situ method. Then, the surface of the membranes is modified with zein, a hydrophobic corn protein. The membranes are characterized by TGA, FTIR, scanning electron microscopy (SEM) analysis and oil degradation test. TGA demonstrates higher stability for the membranes with lipase and zein. The FTIR spectrum of pure BC membrane and zein-modified membrane are very similar because of the high zein coating. SEM analysis shows that zein-modified membranes with lipase present smaller amounts of pores. Finally, using soy oil, lipase degrades oil even after immobilization during the degradation test. © 2024 Wiley-VCH GmbH.

关键词： Nafion membranes

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Conventional Homogeneous Catalytic process with Continuous-typed Microwave and Mechanical Stirrer for Biodiesel Production from Palm Stearin

Conventional Homogeneous Catalytic Process with Continuous-t...

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2012 4th International Conference on chemical,Biological and Environmental engineering

作者： Wilaiporn Garnwitayee Tawiwan Kangsadan Suramate Chalermwisutkul Chemical and Process Engineering Program The Sirindhorn International Thai-German Graduate School of EngineeringKing Mongkut’s University of Technology North BangkokBangkok10800Thailand Communications Engineering Program The Sirindhorn International Thai-German Graduate School of EngineeringKing Mongkut’s University of Technology North BangkokBangkok10800Thailand

In this study,biodiesel production from palm stearin was carried out by applying a mechanical stirrer and using continuous-typed microwave as a heating *** of palm stearin with methanol in the presence of 0.5 wt% NaOH catalyst was *** aims of the study are to determine optimal radiation time and optimal methanol to oil molar *** yield and purity were obtained to compare with the previous work without the *** experiments were carried out at 60 oC of reaction temperature,0.15 W/g of palm stearin and 600 rpm of mixing speed at various radiation times of 40,50,60,80,120 *** different methanol to oil molar ratios of 5:1,6:1 and 7:1 were investigated after obtaining optimal radiation *** results found that radiation time of 50 s and methanol to oil molar ratio of 7:1 were optimum for biodiesel production from palm *** yield and purity obtaining from these conditions were 97.5% and 98.33%,*** fuel properties of stearin biodiesel were determined according to biodiesel standards (ASTM D 6751 and EN 14214).

关键词： Biodiesel,Transesterification,Palm stearin,Microwave irradiation.

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