Modern Chemical Engineering Research Articles

An elastoplastic beam bond model for DEM simulation of deformable materials and breakage behaviors

AbstractIn modern chemical engineering production, numerous elastoplastic materials, often formed into agglomerates, frequently undergo plastic deformation and rupture. Understanding how these materials behave under different conditions is crucial for improving manufacturing processes and material design. In this work, an elastoplastic beam bond model for discrete element method (DEM) simulation was developed, in which a yield criterion is introduced into Timoshenko beam bond method. The model can simulate not just the initial elastic (stretchy) behavior of the materials but also their plastic (permanent) deformation behaviors. The model was applied to central collision of two agglomerates, agglomerate uniaxial compression, and agglomerate‐wall impact cases. It is shown that the updated model could predict the behavior of materials that undergo permanent changes under stress, compared to previous models that only considered elastic behaviors. This could enable more accurate simulations of particulate materials and aid in better process design.

Honeycomb-configured dissipative nanofluid flow within a squeezed channel with entropy generation: regression and numerical evaluations

PurposeNanosized honeycomb-configured materials are used in modern technology, thermal science and chemical engineering due to their high ultra thermic relevance. This study aims to scrutinize the heat transmission features of magnetohydrodynamic (MHD) honeycomb-structured graphene nanofluid flow within two squeezed parallel plates under Joule dissipation and solar thermal radiation impacts.Design/methodology/approachMass, energy and momentum preservation laws are assumed to find the mathematical model. A set of unified ordinary differential equations with nonlinear behavior is used to express the correlated partial differential equations of the established models, adopting a reasonable similarity adjustment. An approximate convergent numerical solution to these equations is evaluated by the shooting scheme with the Runge–Kutta–Fehlberg (RKF45) technique.FindingsThe impression of pertinent evolving parameters on the temperature, fluid velocity, entropy generation, skin friction coefficients and the heat transference rate is explored. Further, the significance of the irreversibility nature of heat transfer due to evolving flow parameters are evaluated. It is noted that the heat transference rate performance is improved due to the imposition of the allied magnetic field, Joule dissipation, heat absorption, squeezing and thermal buoyancy parameters. The entropy generation upsurges due to rising magnetic field strength while its intensification is declined by enhancing the porosity parameter.Originality/valueThe uniqueness of this research work is the numerical evaluation of MHD honeycomb-structured graphene nanofluid flow within two squeezed parallel plates under Joule dissipation and solar thermal radiation impacts. Furthermore, regression models are devised to forecast the correlation between the rate of thermal heat transmission and persistent flow parameters.

Data-driven molecular design and simulation in modern chemical engineering

Data-driven molecular design and simulation in modern chemical engineering

Butane Dehydrogenation: Thermodynamic Modeling and Performance Analysis of Selected Process Simulators

The critical role of process simulation in modern chemical engineering cannot be overstated, with its capacity to facilitate process scale-up, assess alternative designs, and comprehend plant efficiency. This research delves into the performance of three software programs, Cape-Open to Cape-Open (CC), DWSim, and Aspen HYSYS (AH), in modeling butane dehydrogenation. The focus is on their ability to accurately model thermodynamic properties and chemical reaction dynamics. Butane dehydrogenation was evaluated with specific thermodynamic parameters using a Gibbs reactor model with Gibbs minimization. The Soave Redlich-Kwong thermodynamic model was employed to investigate the impact of temperature of 700 °C and pressures of 0.1 MPa and 1.0 MPa on the yield and selectivity of butadiene and butene. The CC and AH simulation results closely agreed with the available experimental data. The consistency of freeware simulators with a commercial simulator was also assessed, with AH serving as the reference standard. It was revealed that CC demonstrates higher consistency with it than DWSim under both low- and high-pressure conditions. This study confirms that CC is a reliable process simulator suitable for use in resource-constrained settings where expensive commercial licenses are prohibitive.

Mesocurriculum modernization of a chemical engineering program: The case of a high-impact regional university in Colombia

In Colombia there are few chemical engineering programs and those have been historically linked to the industrial development of the country, supporting the training needs for industrial development in several regions of economic importance. The southwestern Colombian region contributes with the largest industrial production in the country, and the chemical engineering program of Universidad del Valle has been the only one in the region for 78 years. The last curriculum reform took place 20 years ago and the accelerated technological change urged the adoption of deep changes in the curriculum structure. A student-centered constructivist approach was applied in the faculty-wide transformation in the mesocurriculum and microcurriculum levels, defining the so-called Sensitivities, Capacities and Competencies (SCCs) as the set of attitudes, skills and knowledge necessary for an integral performance of engineers. Those were considered from two standpoints: general and disciplinary formation. In the disciplinary level, the historic traditional pillars of chemical engineering were maintained, but taking advantage on the areas of academic research, development and innovation (R+D+I) expertise demanded by the industry around the university in addition to transversal priority areas for modern chemical engineering professionals. This contribution discussed the elements of the curriculum reform for modernizing the chemical engineering curriculum of a high-impact program in a stablished university with a regional vocation.

Comparison of Derivative-Free Optimization: Energy Optimization of Steam Methane Reforming Process

In modern chemical engineering, various derivative-free optimization (DFO) studies have been conducted to identify operating conditions that maximize energy efficiency for efficient operation of processes. Although DFO algorithm selection is an essential task that leads to successful designs, it is a nonintuitive task because of the uncertain performance of the algorithms. In particular, when the system evaluation cost or computational load is high (e.g., density functional theory and computational fluid dynamics), selecting an algorithm that quickly converges to the near-global optimum at the early stage of optimization is more important. In this study, we compare the optimization performance in the early stage of 12 algorithms. The performance of deterministic global search algorithms, global model-based search algorithms, metaheuristic algorithms, and Bayesian optimization is compared by applying benchmark problems and analyzed based on the problem types and number of variables. Furthermore, we apply all algorithms to the energy process optimization that maximizes the thermal efficiency of the steam methane reforming (SMR) process for hydrogen production. In this application, we have identified a hidden constraint based on real-world operations, and we are addressing it by using a penalty function. Bayesian optimizations explore the design space most efficiently by training infeasible regions. As a result, we have observed a substantial improvement in thermal efficiency of 12.9% compared to the base case and 7% improvement when compared to the lowest performing algorithm.

Waste PET upcycling to conductive carbon-based composite through laser-assisted carbonization of UiO-66

The upcycling of waste polymers into novel materials with high added value is a vital task for modern chemical engineering.

Immobilization of carbonic anhydrase for CO2 capture and utilization.

Carbonic anhydrase (CA) is an excellent candidate for novel biocatalytic processes based on the capture and utilization of CO2. The setup of efficient methods for enzyme immobilization makes CA utilization in continuous bioreactors increasingly attractive and opens up new opportunities for the industrial use of CA. The development of efficient processes for CO2 capture and utilization (CCU) is one of the most challenging targets of modern chemical reaction engineering. In the general frame of CCU processes, the interest in the utilization of immobilized CA as a biocatalyst for augmentation of CO2 reactive absorption has grown consistently over the last decade. The present mini-review surveys and discusses key methodologies for CA immobilization aimed at the development of heterogeneous biocatalysts for CCU. Advantages and drawbacks of covalent attachment on fine granular solids, immobilization as cross-linked enzyme aggregates, and "in vivo" immobilization methods are presented. In particular, criteria for optimal selection of CA-biocatalyst and design of CO2 absorption units are presented and discussed to highlight the most effective solutions. Perspectives on biocatalytic CCU processes that can include the use of CA in an enzymatic reactive CO2 absorption step are eventually presented with a special focus on two examples of CO2 fixation pathways: hybrid enzyme-microalgae process and enzyme cascade for theproduction of carboxylic acids. KEY POINTS: • Covalent immobilization techniques applied to CA are effective for CO2 ERA. • Biocatalyst type and morphology must be selected considering CO2 ERA conditions. • Immobilized CA can offer novel routes to CO2 capture and direct utilization.

ЕКСТРАКЦІЯ ПОЛІФЕНОЛЬНИХ СПОЛУК ІЗ ПРОДУКТІВ ПЕРЕРОБКИ ВИНОГРАДУ НИЗЬКОТЕМПЕРАТУРНИМ ЕВТЕКТИЧНИМ РОЗЧИННИКОМ БЕТАЇН-МОЛОЧНА КИСЛОТА

The development of modern chemical technology and engineering is aimed at the concept of greening. Therefore, the search for effective green solvents for the extraction of natural organic compounds from vegetable raw materials is urgent. The use of DES is appropriate and is of increasing interest due to its environmental, technological, and economic features. DES are prepared from readily available materials with high purities, low cost, nontoxicity, non-flammability, biocompatibility, and biodegradability.In the work, the effect of water on the viscosity of deep eutectic solvent (DES) based on betaine and lactic acid was studied, and an assessment of polyphenolic compounds of grape pomace processing products was carried out with a water content of up to 10%. When 10% of water was added to DES, the viscosity decreased from 16,000.00 to 3,500.00 mPa s, when 25% of water was added, the viscosity decreased exponentially with increasing temperature. Research results showed that water content also affects other physical properties, such as density, with the density of DES decreasing linearly with increasing water content. When performing liquid chromatography-mass-spectrometry during extraction with DES, compared to a traditional solvent, higher peaks are observed, which indicates an increase in the yield of extraction using DES. The main components of grape pomace extract are hydroxycinnamic acids, anthocyanins, anthoxanthins and stilbenes. When determining the influence of the solvent on the composition of the extract, significant differences in the compound profile were found between extraction with a 70% ethanol solution and extraction using DES. A complex mixture of hydroxycinnamic acids and flavonoids was obtained during extraction with DES, while with a traditional solvent -mainly hydroxycinnamic acids. The extractive capacity of DES can be correlated with their physicochemical properties, including H-bonding interactions, polarity, and pH.

Rheological Behavior of Rapeseed Oil Shear Rate 3.3s -1 and 120s -1

Rheology is a branch of science with multiple implications in numerous sectors of industry, also constituting a generous field due to its multidisciplinary character. Thus, solving a problem in rheology calls for knowledge from modern mathematics, physics, chemistry, chemical and mechanical engineering, and materials science. Driven by the appearance of new materials (plastics and synthetic fibers, varnishes and paints, detergents, adhesives, pharmaceutical and cosmetic products, biological mate

ВИЗНАЧЕННЯ ЕЛЕКТРОХІМІЧНИХ ВЛАСТИВОСТЕЙ ПРИРОДНИХ ІОННИХ РІДИН НОВОГО ПОКОЛІННЯ

Nowadays, the development of modern chemical technology and engineering is aimed at the concept of greening and implementation of "green" technologies. Therefore, the study of deep eutectic solvents (DES), which arecheap and environmentally friendly, is of particular importance. DES are a class of novel green solventswith a wide range of properties and applications. In the work, 6 solvents were synthesized using choline chloride, lactic acid, proline, betaine, propanol, and urea. These constituents jointly determine the nature of the synthesized DESs and their electrochemical behavior. The knowledge of physicochemical, electrochemical properties of DESs is also valuable to DESs practical applications. Electrical conductivity indicates the strength with which DESs can conduct electricity. The focus of the investigation is physicochemical properties (electrical conductivity, electrochemical window) deep eutectic solvents (DESs). The formation of hydrogen bonds between the components was confirmed and the electrochemical characteristics of the synthesized ionic liquids were determined. The conducted studies showed that urea and lactic acid arethe most suitable compounds for the formation of DES. DESs have been synthesized using choline chloride, Betaine and Proline as hydrogen bond acceptors (HBAs). Choline chloride-urea, Choline chloride-lactic acid, Sodium acetate-lactic acid, Choline chloride-propanediol, Proline-lactic acid, Betaine-lactic acid were synthesized. The electrical conductivity of deep eutectic solvents was measured and the width of the electrochemical window was evaluated using cycling voltammetry. FTIR-ATR was carried out to confirm the formation of the DESs. FT-IR results confirmed that H-bonds, occurring between two components in DES, were the main force leading to the eutectic formation. Adding water in quantity 1...25% leads to a decrease in the width of the electrochemicalwindow from 1.33to 1.21 V and increase in electrical conductivity from 0.39 to 2.07 S/m.

Investigation of catalytic hydrogen sensors with platinum group catalysts

Environmental deterioration and limited resources of hydrocarbons push the development of alternative power sources. One of the most promising energy carriers is hydrogen. However, handling hydrogen is more hazardous than the use of hydrocarbons because it has a significantly wider flammable range. Thus the development of new sensors for preventing hydrogen leakage is the actual task of modern materials science and chemical engineering. In this work, the response of catalytic sensors to hydrogen with different catalysts of platinum group (Pt, Pd, Ir, Rh, Pt + Pd, Pt + Pd + Rh, Pt + Pd + Ir) in the pre-explosion concentration range is studied. Temperature dependencies of sensitivity are discussed. A hysteresis in sensor response is observed during the cycling of the supply voltage. This phenomenon can be explained by partial transformation of platinum group metal oxides into metallic phase at a temperature of more than 500 °C and reverse metal oxidation at temperatures less than 400 °C. It has been shown that the sensors with catalysts containing Ir and Rh demonstrate more preferable characteristics for practical applications.

Operational trend prediction and classification for chemical processes: A novel convolutional neural network method based on symbolic hierarchical clustering

In modern industrial chemical engineering plants, the quality of the product is closely related not only to the process design but also to the efficiency of human operation. Currently, single-step prediction models are adopted by process engineers to estimate the immediate system response. However, those single-step prediction models are limited as they don’t enable the operator to visualize the complete series of effects associated with the operation in the long run. In order to help make prescient predictions, this paper proposes a novel symbolic hierarchical clustering (SHC) based convolutional neural network (CNN) method for trend prediction and classification. Firstly, the raw historical operation data series are symbolized from numerical values to strings according to their distinct characteristics. Secondly, the hierarchical clustering method is used to eliminate the low-frequency operation trends and to determine and label the types of operational trends for the symbolized dataset. Subsequently, the categorized dataset and its respective label are fed into a specially tailored CNN for the training of the CNN model for trend classification. Finally, to demonstrate the effectiveness of the proposed SHC-CNN algorithm, the proposed method is applied to the methanol production process of Hainan Petrochemical Co., Ltd. to predict and classify its main operational trends. In addition, the superiority of SHC-CNN operational trend prediction is demonstrated through the comparison with traditional neural networks.

Porous polyacrylonitrile/graphene oxide nanofibers designed for high efficient adsorption of chromium ions (VI) in aqueous solution

• PAN/GO nanofibers with 5–200 nm pores were fabricated for efficient Cr(VI) removal. • BET specific surface area of the porous nanofibers was 164.2 ± 10.8 m 2 g −1. • Maximum experimental adsorption capacity of Cr(VI) was up to 382.5 ± 6.2 mg/g. • Reusability of the porous nanofibers was at least 20 times cycles. • Simple, low cost, green of one-step electrospinning had great industrial potential. Development of efficient adsorbent with low cost, simple and green production process, and zero secondary pollution for Cr(VI) removal in industrial applications is a great challenge for modern chemical and materials engineering. Here, we developed a new strategy for preparation of porous polyacrylonitrile (PAN)/graphene oxide (GO) nanofibers by simple one-step electrospinning of PAN/GO solution in N,N-dimethylformamide (DMF)/H 2 O mixed solvent. The resultant porous PAN/GO nanofibers possessed abundant nanopores (5–200 nm) and thus huge Brunauer-Emmett-Teller (BET) specific surface area (164.2 ± 10.8 m 2 g −1 ) and excellent interfacial compatibility. The porous structure maximized the adsorption function of the doped GO nanosheets for Cr(VI) ions, an unprecedented experimental Cr(VI) ions adsorption capacity of 382.5 ± 6.2 mg/g was achieved. And the porous PAN/GO nanofibers also exhibited excellent regeneration, after 20 times adsorption–desorption test, the desorption efficiency of the Cr(VI) ions stably maintained more than 75%. More importantly, compared to the current complex chemical synthesis and material structure design methods of Cr(VI) ions adsorbent, the simple one-step electrospinning fully showed great technical advantages for industrial applications including efficient (100% raw material utilization), green (no any harmful chemical by-products), low cost (only PAN and 1.98 wt% GO). Therefore, we suggested that the porous PAN/GO nanofibers will be a promising candidate in industrial applications as a solid adsorbent for Cr(VI) ions adsorption.

Experimental methods in chemical engineering: Thermogravimetric analysis—TGA

AbstractThermogravimetric analysis (TGA) is a quantitative analytical technique that monitors the mass of a sample from 1 mg to several g as a furnace ramps temperature to as high as 1600°C under a stable or changing gas flow. The first gravimetric test was in 27 BC when Vitruvius measured limestone's change of mass as it calcined to lime. In modern chemical engineering, researchers apply the technique to derive conversions, kinetics, and mechanisms for any process with a change of mass by isothermal, non‐isothermal, and quasi‐isothermal methods. The mass drops as the sample decomposes, volatile compounds evaporate, or the oxidation state decreases, while in reactive environments (with O2, for example), the mass of transition metals may increase. TGA is incapable of detecting phase transitions, polymorphic transformations, or reactions for which mass is invariant. DSC or DTA couple with TGA to help deconvolute a DSC plot by separating physical changes from chemical changes. Evolved gas analysis techniques monitor the gaseous products exiting the TGA furnace on‐line as the temperature ramps. A bibliometric map of keywords from articles citing TGA indexed by Web of Science in 2016 and 2017 identified five research clusters: nanoparticles, performance, and films; crystal structures, acid, and oxidation; composites, nanocomposites, and mechanical properties; kinetics, pyrolysis, and temperature; and adsorption, water and wastewater, and aqueous solutions. This review provides an overview of the basic principles of modern TGA.

Powell–Eyring fluid flow towards an isothermal sphere in a non-Darcy porous medium

Non-Newtonian viscoelastic fluid flow past an isothermal sphere embedded in non-Darcy porous medium is examined numerically in this work. To be specific, the non-Newtonian Powell–Eyring fluid in the presence of both the heat and mass characteristics is mathematically modelled in terms of differential system. A non-Darcy drag force model is employed to simulate the effects of linear porous media drag and second-order Forchheimer drag. The surface of the sphere is maintained at a constant temperature and concentration. The numerical solution of the resultant system is reported via the Keller box method. Both tabular and graphical forms are adopted to identify the variations in Powell–Eyring fluid velocity, Powell–Eyring fluid temperature, and Powell–Eyring fluid concentration. In addition, the surface physical quantities, namely, skin friction and heat and mass transfer rates, are explored. The obtained observations are validated with earlier Newtonian studies. We found an excellent match in this regard. It is found that the velocity is reduced with increasing fluid parameter (ε), Forchheimer parameter (Λ), and tangential coordinate (ξ). In contrast, the temperature and concentration are increasing with increasing value of ε. A very slight increase in velocity is seen with an increase in the local non-Newtonian parameter, δ. But the temperature and concentration decrease slightly with an increase in δ. An increase in Darcy parameter enhances velocity but reduces both temperature and concentration. The present study finds an extensive array of applications in modern nuclear engineering, mineral and chemical process engineering, nuclear waste in geomaterial repositories, petroleum product filtration, and insulation systems.

Does Chemical Engineering Research Have a Reproducibility Problem?

Concerns have been raised in multiple scientific fields in recent years about the reproducibility of published results. Systematic efforts to examine this issue have been undertaken in biomedicine and psychology, but less is known about this important issue in the materials-oriented research that underpins much of modern chemical engineering. Here, we relate a dramatic historical episode from our own institution to illustrate the implications of performing reproducible research and describe two case studies based on literature analysis to provide concrete information on the reproducibility of modern materials-oriented research. The two case studies deal with the properties of metal-organic frameworks (MOFs), a class of materials that have generated tens of thousands of papers. We do not claim that research on MOFs is less (or more) reproducible than other subfields; rather, we argue that the characteristics of this subfield are common to many areas of materials-oriented research. We conclude with specific recommendations for action by individual researchers, journal editors, publishers, and research communities.

Progress in molecular-simulation-based research on the effects of interface-induced fluid microstructures on flow resistance

Abstract In modern chemical engineering processes, solid interface involvement is the most important component of process intensification techniques, such as nanoporous membrane separation and heterogeneous catalysis. The fundamental mechanism underlying interfacial transport remains incompletely understood given the complexity of heterogeneous interfacial molecular interactions and the high nonideality of the fluid involved. Thus, understanding the effects of interface-induced fluid microstructures on flow resistance is the first step in further understanding interfacial transport. Molecular simulation has become an indispensable method for the investigation of fluid microstructure and flow resistance. Here, we reviewed the recent research progress of our group and the latest relevant works to elucidate the contribution of interface-induced fluid microstructures to flow resistance. We specifically focused on water, ionic aqueous solutions, and alcohol–water mixtures given the ubiquity of these fluid systems in modern chemical engineering processes. We discussed the effects of the interface-induced hydrogen bond networks of water molecules, the ionic hydration of ionic aqueous solutions, and the spatial distributions of alcohol and alcohol–water mixtures on flow resistance on the basis of the distinctive characteristics of different fluid systems.

Flow-resistance analysis of nano-confined fluids inspired from liquid nano-lubrication: A review

How to reduce flow resistance of nano-confined fluids to achieve a high flux is a new challenge for modern chemical engineering applications, such as membrane separation and nanofluidic devices. Traditional models are inapplicable to explain the significant differences in the flow resistance of different liquid–solid systems. On the other hand, friction reduction in liquid nano-lubrication has received considerable attention during the past decades. Both fields are exposed to a common scientific issue regarding friction reduction during liquid–solid relative motion at nanoscale. A promising approach to control the flow resistance of nano-confined fluids is to reference the factors affecting liquid nano-lubrication. In this review, two concepts of the friction coefficient derived from fluid flow and tribology were discussed to reveal their intrinsic relations. Recent progress on low or ultra-low friction coefficients in liquid nano-lubrication was summarized based on two situations. Finally, a new strategy was introduced to study the friction coefficient based on analyzing the intermolecular interactions through an atomic force microscope (AFM), which is a cutting-point to build a new model to study flow-resistance at nanoscale.

Chemical Engineering in the "BIO" World.

Modern Chemical Engineering was born around the end of the 19th century in Great Britain, Germany, and the USA, the most industrialized countries at that time. Milton C. Whitaker, in 1914, affirmed that the difference between Chemistry and Chemical Engineering lies in the capability of chemical engineers to transfer laboratory findings to the industrial level. Since then, Chemical Engineering underwent huge transformations determining the detachment from the original Chemistry nest. The beginning of the sixties of the 20th century saw the development of a new branch of Chemical Engineering baptized Biomedical Engineering by Peppas and Langer and that now we can name Biological Engineering. Interestingly, although Biological Engineering focused on completely different topics from Chemical Engineering ones, it resorted to the same theoretical tools such as, for instance, mass, energy and momentum balances. Thus, the birth of Biological Engineering may be considered as a Darwinian evolution of Chemical Engineering similar to that experienced by mammals which, returning to water, used legs and arms to swim. From 1960 on, Biological Engineering underwent a considerable evolution as witnessed by the great variety of topics covered such as hemodialysis, release of synthetic drugs, artificial organs and, more recently, delivery of small interfering RNAs (siRNA). This review, based on the activities developed in the frame of our PRIN 2010-11 (20109PLMH2) project, tries to recount origins and evolution of Chemical Engineering illustrating several examples of recent and successful applications in the biological field. This, in turn, may stimulate the discussion about the Chemical Engineering students curriculum studiorum update.