Particle‐laden flows in a vertical channel were simulated using an Eulerian–Eulerian, Anisotropic‐Gaussian (EE‐AG) model. Two sets of cases varying the overall mass loading were done using particle sizes corresponding to either a large or small Stokes number. Primary and turbulent statistics were extracted from these results and compared with counterparts collected from Eulerian–Lagrangian (EL) simulations

Soluble and miscible states are two important thermodynamic states in academic research and practical applications but their quantitative distinctions are still fuzzy. In this study, for the first time, the mathematical formulations of the quantitative criteria for distinguishing the thermodynamic soluble and miscible states are analytically developed by means of the Flory–Huggins solution theory and

Bubble formation from a downward‐pointing capillary nozzle was investigated in this study. The experiments were conducted at gas flow rate of 40–5,400 mL/h and inner nozzle radius of 0.030–0.255 mm. Experimental results show that microbubbles are formed continuously at moderate Weber number, which was not reported in pervious investigations with injecting gas through an upward‐pointing capillary nozzle

We introduce a straightforward method for the preparation of novel starch‐based ultramicroporous carbons (SCs) that demonstrate high CH4 uptake and excellent CH4/N2 selectivity. These SCs are derived from a combination of starch and 1–6 wt. % of acrylic acid, and the resulting materials are amenable to surface cation exchangeability as demonstrated by the formation of highly dispersed K+ in carbon

The kinetics of propane dehydrogenation over single‐Pt‐atom‐doped Ga2O3 catalyst has been examined by combining density functional theory calculations and microkinetic analysis. The doping of Pt not only can improve the selectivity of the Ga2O3 catalyst by hindering the deep dehydrogenation reactions but also helps to achieve a long‐term stability by improving the resistance of Ga2O3 to hydrogen reduction

A model was developed to describe the nitration of cellulose in mixed acids used in the production of military grade nitrocellulose. Acid dissociation, swelling, diffusion, and chemical reaction were considered to model the nitration of industrially important cellulose materials for given reaction times and conditions. This model is supported by experimental work conducted to measure the dynamics of

Amine‐based chemical absorption has become the most mature technology among carbon dioxide capture processes, featuring the advantages of high separation efficiencies and its simplicity to attach it to existent industrial facilities. Nevertheless, further improvements on its performance are required in order to implement this technology to a wider extent. Energy expenditure at the solvent regeneration

The aim of this study was to investigate the influence of humic substances (HS) on volumetric oxygen‐transfer coefficient (K La) under different turbulence intensities at the air–water interface. The experiments were carried out in an oscillating grid tank which provided three levels of turbulence intensities (Reynolds numbers of 5,116, 10,316, and 15,433). For each turbulence level, 15 different HS

Handling molten sulfur is inherently difficult due to liquid sulfur's extreme rheological behaviour. Upon melting at 115°C, sulfur's viscosity remains low until reaching 160°C, the λ‐transition region, where the viscosity increases to a maximum of 93,000 × 10−3 Pa∙s at 187°C. Within this study, our previous viscosity measurements for pure liquid elemental sulfur have been discussed along with new measurements

Tubular carbon molecular sieve (CMS) membranes have been recognized as a potential module for commercial application due to its high mechanical strength and large surface area. However, the carbon layer uniformity was restricted by substrate texture and dope fluidity when the dip‐coating method was used. This study evaluated the influence of various parameters of dip‐coating with an integrated vacuum‐assisted

Based on a self‐established cold‐flow experimental device, the pressure drop in a cocurrent downflow three‐phase moving bed was investigated under a wide range of gas, liquid, and solid flow rates during dynamic and steady‐state operation. The results showed that for the startup of the bed, since the first bed layer packed by fall‐falling of particles had lower voidage, it would take at least one bed

The solubility of CO2 in three cellulose‐dissolving ionic liquids (1‐ethyl‐3‐methylimidazolium diethylphosphate, [Emim][DEP], 1‐allyl‐3‐methylimidazolium chloride, [Amim][Cl], and 1‐butyl‐3‐methylimidazolium chloride, [Bmim][Cl]) at temperatures within 298 and 356 K and pressures up to 6.5 MPa was determined using a Van Ness‐type apparatus (static isochoric). It was demonstrated that this device can

We investigated the flow of viscoelastic surfactant (VES) solutions, an important type of fracturing fluids for unconventional hydrocarbon recovery, through a diverging–converging microfluidic channel that mimics realistic unit in porous media. Newtonian fluid and viscoelastic hydrolyzed polyacrylamid Appendix S1: Supporting Information e (HPAM) solution were used as control groups. We vary Deborah

In solar thermal utilization, effective photo capture and photothermal conversion are crucial. Improving the nonradiative transition rate of photoexcited electrons is important to enhance the photothermal conversion efficiency and develop efficient solar thermal utilization. Herein, we designed a new kind of light absorption‐enhanced and efficient photothermal conversion material, namely, Fe2O3‐functionalized

Membrane emulsification has the potential to revolutionize the energy‐efficient production of uniform emulsions and dispersions, relevant to diverse fields from pharmaceutical active ingredient controlled release particles to Fast Moving Consumer Goods. A novel highly robust single‐pass continuous phase crossflow system has been developed providing dispersed phase concentrations up to 40% vol/vol and

This paper presents a novel deep learning based data‐driven optimization method. A novel generative adversarial network (GAN) based data‐driven distributionally robust chance constrained programming framework is proposed. GAN is applied to fully extract distributional information from historical data in a nonparametric and unsupervised way without a priori approximation or assumption. Since GAN utilizes

The spontaneous rise of Newtonian liquids in closed‐end capillaries is investigated with three different organics. Rise rate and equilibrium height are significantly reduced by a compression induced minor elevation in air pressure within the capillaries. We verify our earlier mathematical analysis quantifying viscous dissipation within air, and also show that the dynamic contact angle plays a material

Seven typical quaternary ammonium ionic liquids, amino acid ionic liquids and imidazolium ionic liquids were synthesized, characterized and investigated as co‐catalyst for the sulfuric acid catalyzed isobutane alkylation. The results show that the introduction of [OPSIm][HSO4] or [Pr3NPS][HSO4] both leads to a better catalytic performance and higher quality of alkylate products. The molecular dynamic

Machine learning (ML) is experiencing an immensely fascinating resurgence in a wide variety of fields. However, applying such powerful ML to construct subgrid interphase closures has been rarely reported. To this end, we develop two data‐driven ML strategies (i.e., artificial neural networks and eXtreme gradient boosting) to accurately predict filtered subgrid drag corrections using big data from highly

We present a new strategy to estimate the temperature dependent vapor–liquid equilibria and solvation free energies of dilute neutral molecules based on only their estimated solvation energy and enthalpy at 298 K. These two pieces of information coupled with matching conditions between the functional forms developed by Japas and LeveltSengers for near critical conditions and by Harvey for low and moderate

This article investigated the fluidization of sands and small Geldart A biomass mixtures. The mixture fluidized like Geldart A type particles with a uniform bed expansion regime before bubbling. The video recorded color distance between pure sands and sands–biomass mixtures was used to estimate the sands–biomass mixing. The coarse‐grained computational fluid dynamics–discrete element method with a

The inner and outer surfaces of a porous hollow fiber polysulfone support are compared as substrates for the synthesis of polyamide thin‐film composite (TFC) membranes by interfacial polymerization. While both surfaces have pores common of microfiltration membranes, the inner surface has a larger pore diameter than the outer surface (2,700 nm compared to 950 nm). The inner TFC membrane showed higher

Transport of suspensions consisting of monodisperse adhesive microparticles in a pressure‐driven duct flow with the Reynolds number in the range of 5.4–108 is analyzed by means of a coupled lattice Boltzmann method with the discrete element method. The influence of the adhesion on migration and agglomeration of particles is investigated. The results show that the suspensions undergo a transition from

Commercialized catalysts are often needed in multiton quantities for industrial deployment. Although scalable, manufacturing methods to produce catalysts at quantity often produce materials with an ensemble of physical and chemical characteristics. This work explores an aerosol reactor to synthesize homogeneous, uniform catalyst materials in order to develop correlations between key chemical and physical

The aim of this study was to investigate the effect of feed time of the oil phase on the average droplet size of Pickering emulsions produced in stirred tanks. Three types of impellers were tested: RT, up‐pumping PBT (PBTU), and down‐pumping PBT (PBTD). All the impellers were tested at two sizes, T/3 and T/2. All configurations were compared at constant tip speed, power per mass, and impeller Reynolds

We propose a measure to quantify the modularity of industrial production (manufacturing) systems and optimization formulations to compute it. From a manufacturing perspective, we argue that a system is deemed modular if: (a) the equipment units that comprise it form clusters (modules) of dense connectivity (i.e., difficult module assembly tasks are performed off‐site), (b) connectivity between modules

Even though it is widely known that mechanical properties of papers are dependent upon fiber morphology such as fiber length and cell wall thickness, existing macroscopic models are limited in describing the microscopic traits of pulp. Thus, we proposed a multiscale model by integrating a macroscopic model (i.e., Purdue model) and a microscopic model (i.e., kinetic Monte Carlo algorithm) to capture

We report new experimental data on concentration‐dependent molecular diffusion coefficient of ethane in toluene at temperatures ranging from 21 to 125°C and pressures up to 4.14 MPa. An analytical model has also been developed for estimation of the diffusion coefficient utilizing the experimental data of the interface velocity as a result of swelling and the rate of gas dissolution in the liquid phase

Catalytic fixed‐bed reactors with a low tube‐to‐particle diameter ratio are widely used in industrial applications. The heterogeneous packing morphology in this reactor type causes local flow phenomena that significantly affect the reactor performance. Particle‐resolved computational fluid dynamics has become a predictive numerical method to analyze the flow, temperature, and species field, as well

Metal sulfide catalysts for ultra‐deep hydrodesulfurization of diesel generally lose a fraction of their catalytically active sites during reactor startup. The underlying mechanisms are discussed. A laboratory diagnostic tool consisting of three probe molecules is developed for testing metal sulfide catalysts' start‐of‐run (SOR) activity maintenance. It is found that a significant fraction of the active

Radioactive particle tracking (RPT) is one of the most widely used non‐intrusive velocimetry technique for multiphase reactors. The large volume of interrogation and the presence of internals limit the application of RPT in large‐scale real‐world systems. The main challenge lies in having fast reconstruction algorithms applicable to conventional (i.e., bubble columns, fluidized beds, etc.) as well

This article introduces the application of a novel supersaturation control (SSC) approach for the crystallization of heat‐sensitive materials. Traditional SSC implements parabolic temperature profile with slow initial cooling that maximizes growth over nucleation, however, which may also promote heat degradation. The proposed semibatch SSC fixes the crystallization temperature to a sufficiently low

A two‐time‐scale system involves both fast and slow dynamics. This article studies observer design for general nonlinear two‐time‐scale systems and presents two alternative nonlinear observer design approaches, one full‐order and one reduced‐order. The full‐order observer is designed by following a scheme to systematically select design parameters, so that the fast and slow observer dynamics are assigned

This study aims to develop a sustainability‐interval‐index (SII) conceptual framework with life‐cycle considerations which can incorporate the opinions/preferences of multiple stakeholders in the complex decision‐making processes and address the decision‐making matrix composed by multiple types of data for multiactor life cycle ranking of industrial systems. The multiactor fuzzy best‐worst method which

We quantify the ability of the two‐fluid Euler–Euler model to predict the overall gas hold‐up during two‐phase flow in vertical columns using a combination of experiments and simulations. Gas hold‐up in a bubble column and gas hold‐up in the less‐frequently studied co‐current flow are investigated. For homogeneous flow characterized by nearly uniform bubble size, Euler–Euler model predictions are within

Recently, the selective removal of H2S and CO2 has been highly desired in natural gas sweetening. Herein, four novel azole‐based protic ionic liquids (PILs) were designed and prepared through one‐step neutralization reaction. The solubility of H2S (0–1.0 bar), CO2 (0–1.0 bar), and CH4 (0–5.0 bar) was systematically measured at temperatures from 298.2 to 333.2 K. NMR and theoretical calculation were

A methodology for particle‐resolved simulation of dense suspensions of flexible cylindrical particles in Newtonian liquid flow is described. It is based on the Lattice–Boltzmann method for solving the liquid flow and an immersed boundary method for imposing no‐slip at the particle surfaces and providing the distribution of liquid–solid interaction forces over the particle surfaces. These forces—along

The implementation of traditional sensors is a drawback when investigating mass transfer phenomena within microstructured devices, since they disturb the flow and reactor characteristics. An Arduino based slider setup is developed, which is equipped with a computer‐vision system to track gas–liquid slug flow. This setup is combined with an optical analytical method allowing to compare experimental

Sudden fractures in rigid ceramic filter tubes hinder the stable long‐term operation of advanced power‐generation processes. In this study, variations in the dynamic pressure characteristics of the inner wall of filter and the outlet concentration with the diameter of leakage during the filtration and pulse jet cleaning process are investigated using high frequency sensors and optical particle spectrometry

Although ion dehydration in confined water is ubiquitous in many important processes concerning ion adsorption, transport and separation, and so forth, few theoretical models have been developed to unravel the mechanism of dehydration in confined space. Herein, a molecular model is proposed by weighing the molecular orientation of surrounding water within the first hydration shell, and then this model

An easily machined novel flow field with controllable pressure gradient across adjacent channels was designed and a two dimensional, across‐the‐channel, two‐phase model was developed to study the gas transport and water removal of the novel configuration. The effect of channel‐rib width ratio, GDL thickness and pressure gradient on the profiles of oxygen concentration and water saturation within the

Decarbonization of the power sector offers ammonia industry an opportunity to reduce its CO2 emissions through sector coupling. Extending from our previous work, we propose a power‐based process for ammonia and nitric acid production. The coupling of nitric acid production facilitates highly efficient heat integration between steam electrolysis and the rest of the process. We investigate the economic

The exothermicity of oxidative coupling of methane (OCM) renders a cooled packed‐bed reactor impractical or impossible. Recently, we proposed an adiabatic autothermal reactor as a solution to this problem and reported the first results for stable autothermal operation (AO) with feed at ambient temperature. AO on the ignited branch is possible only in the region of steady‐state multiplicity. High per‐pass

We investigate the average drag, lift, and torque on static assemblies of capsule‐like particles of aspect ratio 4. The performed simulations are from Stokes flow to high Reynolds numbers (0.1 ≤ Re ≤ 1,000) at different solids volume fraction (0.1 ≤ ɛs ≤ 0.5). Individual particle forces as a function of the incident angle ϕ with respect to the average flow are scattered. However, the average particle

We prepared a one‐stage microfluidic‐based method for continuous synthesis of cobalt (Co) nanoparticles over reduced graphene oxide (rGO) to produce Co/rGO composites. These were generated by the coreduction of Co2+ ions and GO with NaBH4 which was confined within discrete aqueous plugs segmented by octane as continuous phase. Owing to the excellent transfer properties from recirculation in these plugs

A novel rheometer to study the behavior of granular materials in an aerated bed of particles has been developed. The device, called the aerated bed virtual Couette rheometer, is shown to be able to measure the shear stresses in the quasi‐static and in the intermediate flow regimes. To validate the instrument, a Newtonian fluid of known viscosity was first sheared. The device was then used for measuring

Low temperature plasmas (LTP) are a unique class of open‐driven systems in which chemical reactions are unpredictable using established concepts. The terminal state of chemical reactions in LTP, termed the superlocal equilibrium state, is hypothesized to be defined by a proposed set of state variables. Using a LTP reactor wherein the state variables have been measured, it is shown that CO2 spontaneously

In 2016, we introduced the concept of model‐predictive safety (MPS; Ahooyi et al, AIChE J. 2016; 62:2024‐2042). MPS is a proposed innovation in functional safety systems to methodically account for process nonlinearities and variable interactions to enable predictive, prescriptive actions, while existing functional safety systems generally react when individual process variables exceed thresholds.

This article examines the mechanical response of flexible fiber packings subject to triaxial compression. Short fibers yield in a manner similar to typical granular materials in which the deviatoric stress remains nearly constant with increasing strain after reaching a peak value. Interestingly, long fibers exhibit a hardening behavior, where the stress increases rapidly with increasing strain at large

In this article, we study shale gas pad development under natural gas price uncertainty. We optimize the sequence of operations, gas curtailment, and storage on a single pad to maximize the net present value. The optimization problem is formulated as an mixed‐integer linear programming model, which is similar to the one proposed by Ondeck et al. We investigate how natural gas price uncertainty affects

In this article, we developed a pore‐scale model of integrated lattice Boltzmann method and cellular automata to investigate competitive growth of aerobic nitrite and ammonium oxidizers in a bioreactor. The results showed that inlet nutrient concentrations have significant effects on maximum biofilm concentration, ratio of microorganisms' concentrations, growth pattern, and time. The local availability

The rheology of non‐Newtonian fluids in agitated vessels is complex making equipment sizing more an art than a science. To increase our understanding and to resolve the data gap for computational fluid dynamics validation, we present a detailed particle image velocimetry study of the hydrodynamics of Carbopol encountered in a 70 L mechanically mixed (A310) tank at three different rotational speeds

Discrete particle simulation can explicitly consider interparticle forces and obtain microscopic properties of the fluidized cohesive particles, but it is computationally expensive. It is thus pivotal to link the microscopic discrete properties to the macroscopic continuum description of the system for large scale applications. This work studies the fluidization of cohesive particles through the coupled

It is essential to predict the cavern boundary accurately for investigating the cavern characteristics and achieving efficient mixing of the pseudoplastic fluids. The distribution characteristics of apparent viscosity of xanthan gum solutions at different mass concentrations stirred by the impeller of perturbed six‐bent‐bladed turbine (6PBT impeller) were numerically investigated through the computational

In the present study, flow homogenization by distributors in chemical apparatus is studied as a process of flow control and its mechanism is reconsidered from the model of resistance to the model of radial flow. This process is composed of four consecutive behaviors: the generation, distribution, conversion of the radial flow and the momentum transfer of axial flow. Based on these flow behaviors, the

Molecular dynamics simulations were performed to study combinations of [AcO]−, [TfO]−, [BF4]−, and [PF6]− anions paired with imidazolium cations of increasing alkyl chain length to elucidate the roles of anions and cations in solvating ibuprofen. Our simulation results revealed that ionic liquids (ILs) with strong ibuprofen solvation capacity should possess strong van der Waals force from cations and

To study flow dynamics in a fixed‐bed reactor, experiment and numerical simulation are used. In this work, the flow dynamics in a fixed‐bed reactor filled with porous particles was simulated. For verification, experimental data were used. Porous particles were prepared from grains with sizes from 0.2 to 2.0 mm. Porous particles made by sintering grains in a muffle furnace. The study of pressure drop

In our prior work (Ind Eng Chem Res, 2015, 54, 10638‐10644), hydrodeoxygenation (HDO) kinetics of guaiacol, a well‐known model compound of bio‐oil, over Pt/AC (activated carbon) catalysts were investigated under integral operating conditions. It was found that the pseudo‐homogeneous plug‐flow model utilizing these kinetics describes the experimental observations well (with normalized RMS error = 7

Despite the extensive potential of zeolitic imidazolate framework (ZIF) membranes in gas separation, the development of continuous, oriented ZIF membranes onto a polymeric substrate remains a significant challenge. This is presumably due to weak adhesion, and insufficient heterogeneous nucleation sites on the polymer surface. Herein, a layer of horizontally aligned poly(sodium‐4‐styrene sulfonate)‐modified

Due to variety of scale dynamics evolved in gas–solid flows, most of its numerical description is limited to expensive short durations. This has made the slow processes therein, such as the chemical species conversion, to be out of an appropriate reach. In this work, an application of the transport‐based recurrence computational fluid dynamics (CFD) has been introduced for the fast modeling of passive