Chemical Engineering Commons^™

Selective Reduction Of Trivalent Iron In Zinc Ferrite Using Elemental Sulphur, B T. Berdiyarov, Sh T. Khojiev, J B. Ismailov, S T. Matkarimov, Sh O. Ismatov

Technical science and innovation

In this article, the process laws and technological aspects of the process of sintering the zinc-containing waste of a zinc plant with technical sulfur are considered. Zinc cake is obtained during the sulfuric acid leaching of calcined zinc ores and contains about 20% zinc and additional metals such as indium, cadmium, lead and copper. Copper cakes are somewhat difficult to work with because they contain ferrites and silicates belonging to acid-resistant spinels. Since the chemical and mineralogical composition of zinc production cakes consists of complex oxides, finding ways to process them is one of the actual topics of zinc metallurgy. …

Prototype Catalytic Membrane Reactor For Dimethyl Ether Synthesis Via Co2hydrogenation, Qiaobei Dong, Weiwei L. Xu, Xiao Fan, Huazheng Li, Naomi Klinghoffer, Travis Pyrzynski, Howard S. Meyer, Xinhua Liang, Miao Yu, Shiguang Li

Chemical and Biochemical Engineering Faculty Research & Creative Works

Dimethyl ether (DME) has become attractive as a potential environmentally friendly substitute for diesel and liquefied petroleum gas (LPG) due to its similar properties to those of LPG, high cetane number, but less carbon emissions. In this work, we developed a novel prototype-scale catalytic membrane reactor to synthesize DME directly from CO₂and renewable H₂, which could address the environmental and fuel security issues in a cost-effective way. This membrane reactor was equipped with superior hydrophilic NaA zeolite membranes and bifunctional Cu-ZnO-ZrO₂-Al₂O₃/HZSM-5 catalysts. The effects of the reaction temperature and gas …

Élimination Des Vapeurs Toxiques Par Oxydation : Développement De Procédures D'Évaluation Des Systèmes De Purification De L'Air Des Conduits De Ventilation, Chang-Seo Lee, Fariborz Haghighat, Alireza Haghighat Mamaghani, Zahra Shayegan, Ali Bahloul, Mélanie Huard, Lexuan Zhong, Mitra Bahr

Rapports de recherche scientifique

L'exposition à des composés organiques volatils (COV) dans les lieux de travail peut avoir des effets aigus, notamment sous forme d'irritation de la peau, des yeux, de la bouche et du nez. Certains produits peuvent également provoquer des effets chroniques, comme l'asthme et le cancer. La prévention de tels effets nocifs sur la santé des travailleurs par l'adoption et la mise en œuvre de mesures visant à en éliminer ou à tout le moins réduire le risque s'avère importante. Parmi les approches développées à ce jour pour réduire l'exposition aux polluants de l'air intérieur – dont les COV –, la …

Removal Of Toxic Vapors By Oxidation: Development Of Laboratory Test Procedures For In-Duct Air Cleaning Systems, Chang-Seo Lee, Fariborz Haghighat, Alireza Haghighat Mamaghani, Zahra Shayegan, Ali Bahloul, Mélanie Huard, Lexuan Zhong, Mitra Bahr

Rapports de recherche scientifique

L'exposition à des composés organiques volatils (COV) dans les lieux de travail peut avoir des effets aigus, notamment sous forme d'irritation de la peau, des yeux, de la bouche et du nez. Certains produits peuvent également provoquer des effets chroniques, comme l'asthme et le cancer. La prévention de tels effets nocifs sur la santé des travailleurs par l'adoption et la mise en œuvre de mesures visant à en éliminer ou à tout le moins réduire le risque s'avère importante. Parmi les approches développées à ce jour pour réduire l'exposition aux polluants de l'air intérieur – dont les COV –, la …

Mantle Dynamics Of The North China Craton: New Insights From Mantle Transition Zone Imaging Constrained By P-To-S Receiver Functions, Lin Liu, Stephen S. Gao, Kelly H. Liu, William L. Griffin, Sanzhong Li, Siyou Tong, Jieyuan Ning

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Cratons are generally defined as stable continental blocks with a strong cratonic root that typically is at least ∼200 km thick. Many cratons have undergone little internal tectonism and destruction since their formation, but some of them, such as the eastern part of the North China Craton (NCC), the Dharwar Craton and the Wyoming Craton, have lost their thick cratonic root and become reactivated in recent geological history, leading to widespread Meso-Cenozoic volcanisms. The mechanisms responsible for such decratonization remain debated. To provide new constraints on models leading to decratonization, in this study we stack 612 854 source-normalized P-to-S conversions …

Serpentine Micromixers Using Extensional Mixing Elements, George Tomaras, Chandrasekhar R. Kothapalli, Petru S. Fodor

Physics Faculty Publications

Computational fluid dynamics modeling was used to characterize the effect of the integration of constrictions defined by the vertices of hyperbolas on the flow structure in microfluidic serpentine channels. In the new topology, the Dean flows characteristic of the pressure-driven fluid motion along curved channels are combined with elongational flows and asymmetric longitudinal eddies that develop in the constriction region. The resulting complex flow structure is characterized by folding and stretching of the fluid volumes, which can promote enhanced mixing. Optimization of the geometrical parameters defining the constriction region allows for the development of an efficient micromixer topology that shows …

Development Of An Integrated Salt Cartridge-Reverse Electrodialysis (Red) Device To Increase Electrolyte Concentrations To Biomedical Devices, Efecan Pakkaner, Jessica L. Orton, Caroline G. Campbell, Jamie A. Hestekin, Christa N. Hestekin

Chemical Engineering Faculty Publications and Presentations

Emerging technologies in nanotechnology and biomedical engineering have led to an increase in the use of implantable biomedical devices. These devices are currently battery powered which often means they must be surgically replaced during a patient’s lifetime. Therefore, there is an important need for a power source that could provide continuous, stable power over a prolonged time. Reverse electrodialysis (RED) based biopower cells have been previously used to generate continuous power from physiologically relevant fluids; however, the low salinity gradient that exists within the body limited the performance of the biopower cell. In this study, a miniaturized RED biopower cell …

Supported Metal Bifunctional And Bimetallic Catalysts With Precisely Controlled Structures And Properties, Anhua Dong

Theses and Dissertations

In heterogenous catalysis, metallic nanomaterials play vital roles in numerous chemical processes. However, monofunctional catalysts are greatly impeded in their applications especially in the systems including tandem and/or sequential reaction steps. Besides, the catalytic performance can also be greatly influenced by the particle size, morphology, and geometry of the surface metal atoms.

The goal of this work is to synthesize bifunctional or bimetallic nanoparticles with high metal dispersion and homogenous alloys by rational synthetic strategies to facilitate the catalyst function. Strong electrostatic adsorption (SEA) is an effective and facile methodology to produce well dispersed and uniform nanoparticles. Metal-acid bifunctional catalysts …

Understanding Unsteady Corner Separation Within Wing-Body Junction Flows, Paul G. Winner

Doctoral Dissertations and Master's Theses

Wing-body junction flows, formed at the interface between a wing and fuselage surface, are a complex, coupled, three-dimensional, turbulent flow field. This thesis focused on the unsteady corner separation that develops at the trailing edge of this wing-body junction under certain conditions. A NACA 0015 wing mounted on a flat plate at an angle of attack of 13°was used as the model junction flow field. The wing had an aspect ratio of 8 with a linear washout twist of 15°. The Reynolds number based on the wing chord was Re_c = 4.5 × 10⁵. Time-dependent stereoscopic particle …

Prospective Life Cycle Assessment And Cost Analysis Of Novel Electrochemical Struvite Recovery In A U.S. Wastewater Treatment Plant, Karla G. Morrissey, Leah English, Greg Thoma, Jennie S. Popp Ph.D.

Chemical Engineering Faculty Publications and Presentations

Nutrient recovery in domestic wastewater treatment has increasingly become an important area of study as the supply of non-renewable phosphorus decreases. Recent bench-scale trials indicate that co-generation of struvite and hydrogen using electrochemical methods may offer an alternative to existing recovery options utilized by municipal wastewater treatment facilities. However, implementation has yet to be explored at plant-scale. In the development of novel nutrient recovery processes, both economic and environmental assessments are necessary to guide research and their design. The aim of this study was to conduct a prospective life cycle assessment and cost analysis of a new electrochemical struvite recovery …

Liquid Phase Modeling In Metal Catalysis And In Zeolites, Subrata Kumar Kundu

Theses and Dissertations

Liquid phase processing is often desired for selective product formation, such as during catalytic conversion of biomass, and for purification of waste-water streams. Since the liquid phase environment influences the adsorption properties and reactivity of solid catalysts and porous materials, significant performance changes have been observed as a function of solvent properties for various industrial catalytic and separation processes. There is a need to better understand these solvation effects on processes at solid-liquid interfaces and to develop novel multiscale models that permit one to explore solvation effects on surface catalyzed reactions and during adsorption in porous media such as zeolites. …

Durability Enhancement Of Anion Exchange Membrane Based Fuel Cells (Aemfcs) And Water Electrolyzers (Aemels) By Understanding Degradation Mechanisms, Noor Ui Hassan

Theses and Dissertations

The past several years have seen remarkable progress in renewable energy sources such as solar and wind, showing excellent efficiency and significant cost reduction. The intermittent nature of renewable resources requires them to be integrated with energy storage systems that can hold or convert this excess energy into other forms. Though batteries have been the most popular, it is also possible to store the energy as chemicals and fuels, such as hydrogen (H₂). Hydrogen generation from water electrolysis has been receiving significant attention in recent years. Among the existing water electrolysis technologies, anion exchange membrane electrolyzers (AEMELs) are …

Estimation Of The Bubble Point Pressure Of Multicomponent Reservoir Hydrocarbon Fluids, Benjamin Sunday Usen, Chidi Obi

Makara Journal of Science

This study developed a novel C-sharp (C#) programming language for the estimation of bubble point pressure (BPP) of various hydrocarbon mixtures at equilibrium state. The methodology was based on vapor–liquid equilibrium calculation using Peng Robinson equation of state implementation, thermodynamic equilibrium calculation and Newton-Raphson’s method for the successive substitution of the unknown variables. The equal fugacity constraint can be satisfied by obtaining the equilibrium which serves as a criterion for two or more phases to exist at equilibrium. The problem was resolved by searching for a pressure that will satisfy the two constraints. Complex calculation was performed by successively substituting …

Towards Environmentally Sustainable, High-Performance, Lightweight Composites For Automotive Applications, Jasmin Zamudio Vasquez

Theses and Dissertations

The increasing public demand in the world automotive industry to improve the environmental sustainability of their manufactured vehicles without sacrificing drivers' comfort and safety and the high cost of lightweight materials have driven researchers to reconsider materials used in the automotive application. Thus, this work aims toward the production of environmentally sustainable, high-performance, lightweight composites, utilizing recycled carbon fibers (RCFs) and pyrolyzed tire particles (PTPs) reclaimed from pyro-gasification of CFRP wastes and end-of-life tires (ELTs), respectively, as reinforcements for cardanol-based epoxy resins. The fabricated composites exhibited rubbery-like behavior at 25 °C. Spectroscopic, rheological, physical, thermal, thermomechanical, and mechanical characterizations were …

Preface To Special Issue On Water Electrolysis For Hydrogen Production, Li Li, Jin-Song Hu, Zi-Dong Wei

Journal of Electrochemistry

No abstract provided.

Recent Development Of Low Iridium Electrocatalysts Toward Efficient Water Oxidation, Jing Ni, Zhao-Ping Shi, Xian Wang, Yi-Bo Wang, Hong-Xiang Wu, Chang-Peng Liu, Jun-Jie Ge, Wei Xing

Journal of Electrochemistry

Developing high-performance and low-cost electrocatalysts for oxygen evolution reaction (OER) is the key to implementing polymer electrolyte membrane water electrolyzer (PEMWE) for hydrogen production. To date, iridium (Ir) is the state-of-the-art OER catalyst, but still suffers from the insufficient activity and scarce earth abundance, which results in high cost both in stack and electricity. Design low-Ir catalysts with enhanced activity and stability that can match the requirements of high current and long-term operation in PEMWE is thus highly desired, which necessitate a deep understanding of acidic OER mechanisms, unique insights of material design strategies, and reliable performance evaluation norm, especially …

The Rapid Preparation Of Efficient Mofeco-Based Bifunctional Electrocatalysts Via Joule Heating For Overall Water Splitting, Ao Zhou, Wei-Jian Guo, Yue-Qing Wang, Jin-Tao Zhang

Journal of Electrochemistry

Water electrolysis is an available way to obtain green hydrogen. The development of highly efficient electrocatalysts is a current research hotspot for water splitting, but it remains challenging. Herein, we demonstrate the synthesis of a robust bifunctional multi-metal electrocatalysts toward water splitting via the rapid Joule-heating conversion of metal precursors. The composition and morphology were well regulated via altering the ratio of metal precursors. In particular, the trimetal MoC/FeO/CoO/carbon cloth (CC) electrode revealed the outstanding bifunctional electrocatalytic performance due to the unique composition and large electrochemical active surface area. Typically, the MoC/FeO/CoO/CC catalyst needed low overpotentials of 121 and 268 …

Perovskite-Type Water Oxidation Electrocatalysts, Xiao Liang, Ke-Xin Zhang, Yu-Cheng Shen, Ke Sun, Lei Shi, Hui Chen, Ke-Yan Zheng, Xiao-Xin Zou

Journal of Electrochemistry

The development of energy conversion/storage technologies can achieve the reliable and stable renewable energy supply, and bring us a sustainable future. As the core half-reaction of many energy-related systems, water oxidation is the bottleneck due to its sluggish kinetics of the four-concerted proton-electron transfer (CPET) process. This necessitates the exploitation of low cost, highly active and stable water oxidation electrocatalysts. Perovskite-type oxides possess diverse crystal structures, flexible compositions and unique electronic properties, enabling them ideal material platform for the optimization of catalytic performance. In this review, we provide a comprehensive summary for the crystal structures, electronic structures and synthetic methods …

Surface Structure Engineering Of Feni-Based Pre-Catalyst For Oxygen Evolution Reaction: A Mini Review, Jia-Xin Li, Li-Gang Feng

Journal of Electrochemistry

Nitrite, a widespread raw material, is harmful to human health for long-term consumption. At present, the detection methods of nitrite mainly include chemical analysis, fluorescence, ultraviolet spectrophotometry and chromatography. These methods have ideal sensitivity and selectivity, but also have some characteristics: cumbersome operation, expensive equipment and professional personnel. Therefore, the development of a simple and sensitive nitrite assay is of great significance. In this paper, the Au/rGO/FeOOH composite materials, which revealed good synergistic catalytic performance among the three elements in the composite, were prepared by simple hydrothermal method and reduction method for the first time with large specific surface area …

A Co Porphyrin With Electron-Withdrawing And Hydrophilic Substituents For Improved Electrocatalytic Oxygen Reduction, Hong-Bo Guo, Ya-Ni Wang, Kai Guo, Hai-Tao Lei, Zuo-Zhong Liang, Xue-Peng Zhang, Rui Cao

Journal of Electrochemistry

Understanding factors that influence the catalyst activity for oxygen reduction reaction (ORR) is essential for the rational design of efficient ORR catalysts. Regulating catalyst electronic structure is commonly used to fine-tune electrocatalytic ORR activity. However, modifying the hydrophilicity of catalysts has been rarely reported to improve ORR, which happens at the liquid/gas/solid interface. Herein, we report on two Co porphyrins, namely, NO₂-CoP (Co complex of 5,10,15,20-tetrakis(4-nitrophenyl)porphyrin) and 5F-CoP (Co complex of 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin), and their electrocatalytic ORR features. By simultaneously controlling the electronic structure and hydrophilic property of the meso-substituents, the NO₂-CoP showed higher electrocatalytic activity than …