Chemical Engineering Commons^™

Electrolyte Tailoring For Electrocatalytic Reduction Of Stable Molecules, Jin-Han Li, Fang-Yi Cheng

Journal of Electrochemistry

Reduction of stable molecules such as CO₂ and N₂ is important process in electrochemical energy conversion and storage technologies for electrofuels production. However, for the inert nature of CO₂/N₂ molecule and competitive proton reduction in conventional aqueous electrolytes, selective electrochemical carbon/nitrogen fixation suffers from high overpotential, low reaction rate and low selectivity. While addressing these issues has witnessed substantial advances in electrocatalysts, much less attention has been placed on the electrolytes, which play an important role in regulating the local environment and thus the performance of catalysts under operating conditions. Rational design of electrolytes has …

Research Progress Of Metal-Nitrogen-Carbon Catalysts Toward Oxygen Reduction Reaction Inm Changchun Institute Of Applied Chemistry, Ming-Jun Xu, Jie Liu, Jun-Jie Ge, Chang-Peng Liu, Wei Xing

Journal of Electrochemistry

The development of highly active and stable catalysts toward oxygen reduction reaction (ORR) has been facing severe challenges. In recent years, pyrolytic M-N-C catalysts and metal-organic framework derived materials made the performance of non-noble metal catalysts greatly improved, however, the molecular and atomic level understanding in the reaction active sites and the mechanism are still lacking. Here, we summarize the recent research progress made in the Changchun Institute of Applied Chemistry. We present a microporous metal-organic-framework confined strategy toward the preferable formation of ORR catalysts. Firstly, we studied the active site and proposed a new active site structure for the …

Fuel Cell Performance Of Non-Precious Metal Based Electrocatalysts, Yan-Feng Zhang, Fei Xiao, Guang-Yu Chen, Min-Hua Shao

Journal of Electrochemistry

The commercialization of proton exchange membrane fuel cells (PEMFCs) is hindered by high cost and low durability of Pt based electrocatalysts. Developing efficient and durable non-precious metal catalysts is a promising approach to addressing these conundrums. Among them, transition metals dispersed in a nitrogen (N)-doped carbon support (M-N-C) show good oxygen reduction reaction activity. This article reviews recent progress in M-N-C catalysts development, focusing on the catalysts design, membrane electrode assembly fabrication, fuel cell performance, and durability testing. Template-assisted approach is an efficient way to synthesize M-N-C materials with homogeneously dispersed single atom active site and reduced metal particles, carbides …

Structural Organization And Chemical Activity Revealed By New Developments In Single-Molecule Fluorescence And Orientation Imaging, Tianben Ding

McKelvey School of Engineering Graduate Student Theses & Dissertations

Single-molecule (SM) fluorescence and its localization are important and versatile tools for understanding and quantifying dynamical nanoscale behavior of nanoparticles and biological systems. By actively controlling the concentration of fluorescent molecules and precisely localizing individual single molecules, it is possible to overcome the classical diffraction limit and achieve 'super-resolution' with image resolution on the order of 10 nanometers.

Single molecules also can be considered as nanoscale sensors since their fluorescence changes in response to their local nanoenvironment. This dissertation discusses extending this SM approach to resolve heterogeneity and dynamics of nanoscale materials and biophysical structures by using positions and orientations …

Growth Of Small Particles In Nonequilibrium Plasmas, Necip Berker Üner

McKelvey School of Engineering Graduate Student Theses & Dissertations

Nonequilibrium plasma (NEP) is an extraordinary environment for material synthesis. NEP is comprised of hot electrons with temperatures greater than 10000 K and of cold ions and neutrals that are usually at few hundred kelvins above room temperature. Due to this large difference in species’ temperatures, the assumption of local thermal equilibrium does not hold in NEP. Therefore, NEP can act as a unique processor of mass, and it can transform materials along pathways that are not accessible by methods wherein local thermal equilibrium is valid. For decades, NEPs have been employed in the semiconductor industry to manufacture many thin …

Nanoceria Distribution And Effects Are Mouse-Strain Dependent, Robert A. Yokel, Michael T. Tseng, D. Allan Butterfield, Matthew L. Hancock, Eric A. Grulke, Jason M. Unrine, Arnold J. Stromberg, Alan K. Dozier, Uschi M. Graham

Pharmaceutical Sciences Faculty Publications

Prior studies showed nanoparticle clearance was different in C57BL/6 versus BALB/c mice, strains prone to Th1 and Th2 immune responses, respectively. Objective: Assess nanoceria (cerium oxide, CeO₂ nanoparticle) uptake time course and organ distribution, cellular and oxidative stress, and bioprocessing as a function of mouse strain. Methods: C57BL/6 and BALB/c female mice were i.p. injected with 10 mg/kg nanoceria or vehicle and terminated 0.5 to 24 h later. Organs were collected for cerium analysis; light and electron microscopy with elemental mapping; and protein carbonyl, IL-1β, and caspase-1 determination. Results: Peripheral organ cerium significantly increased, generally more …

Waste Cooking Oil Classification Using Artificial Intelligence Technology, Kar Sin Lau

Student Works (2020-2029)

Palm oil – one of the most common edible oil consumed in Malaysia. It is because Malaysia is one of the countries which supply palm oil to the global market and it is cheap to obtain for the consumer in Malaysia. Most of the Malaysian consume it via food preparation such as deep-frying and cooking. However, due to widely available for Malaysians, consumers also lacking awareness in dealing after using the edible oil. Most of the household consumers discard excess waste cooking oil (WCO) into sewage and with courtesy, some of them stored them in containers and sell to NGOs. …

Quantitative Risk Assessment And Dispersion Modelling Using Aloha For Chlorine Gas Handling Facility, Kusala Uvaraja

Student Works (2020-2029)

Malay-Sino Chemical Industries Sdn Bhd (Lahat) is a chlor-alkali industry consist of Emergency Chlorine Gas Handling Facility (ECGHF) which have the tendency to affect the plant workers and nearby residential area in the event of accidental chlorine gas release. HAZOP tool with risk assessment was used to identify the hazard and quantifying the hazards in order to prioritize the recommendations at the ECGHF. Possible incident scenario was selected from the HAZOP outcome which was the chlorine gas release from the stack due to scrubbing flow failure. The consequences of the released chlorine gas to the atmosphere was simulated by using …

Optimization Of Bioethanol Production, Engine Performance And Exhaust Emissions From Manihot Glaziovii And Sweet Sorghum In A Spark Ignition Engine, Sebayang Abdi Hanra

Student Works (2020-2029)

The ever-increasing fossil fuel consumption over the years is attributable to economic and population growth, which in turn, increases greenhouse gas emissions. Bioethanol is one of the promising solutions to address the depletion of fossil fuels as well as environmental problems. Manihot glaziovii tubers and sweet sorghum grains are inedible feedstocks that can be used for bioethanol production. The carbohydrate content (70%) of these biomasses makes them suitable as feedstocks for bioethanol production. In this study, enzymatic hydrolysis (liquefaction and saccharification) was used to obtain the reduction of sugars. The enzymes α-amylase from Bacillus licheniformis Type XII-A and amyloglucosidase from …

Enhancement Of Graphene Biocompatibility As A Potential Nano-Carrier For Drug Delivery Applications Using Natural Deep Eutectic Solvent, Zainal Abidin Mohamad Hamdi

Student Works (2020-2029)

Graphene has attracted massive interest in numerous biomedical applications such as anti-cancer therapy, drug delivery, bio-imaging and gene delivery. Therefore, it is important to ensure that graphene is nontoxic, and that its cellular biological behavior is safe and biocompatible. Herein, a new route was used to enhance the biocompatibility of graphene as a nano-carrier for potential drug delivery applications, using different compositions of natural deep eutectic solvents (DESs) as functionalizing agents, owing to their capability to introduce various functional groups and surface modifications. To meet this end, eight different combinations of binary and ternary DESs were synthesized using choline chloride …

Plasma And Serum Proteins Bound To Nanoceria: Insights Into Pathways By Which Nanoceria May Exert Its Beneficial And Deleterious Effects In Vivo, D. Allan Butterfield, Binghui Wang, Peng Wu, Sarita S. Hardas, Jason M. Unrine, Eric A. Grulke, Jian Cai, Jon B. Klein, William M. Pierce, Robert A. Yokel, Rukhsana Sultana

Chemistry Faculty Publications

Nanoceria (CeO2, cerium oxide nanoparticles) is proposed as a therapeutic for multiple disorders. In blood, nanoceria becomes protein-coated, changing its surface properties to yield a different presentation to cells. There is little information on the interaction of nanoceria with blood proteins. The current study is the first to report the proteomics identification of plasma and serum proteins adsorbed to nanoceria. The results identify a number of plasma and serum proteins interacting with nanoceria, proteins whose normal activities regulate numerous cell functions: antioxidant/detoxification, energy regulation, lipoproteins, signaling, complement, immune function, coagulation, iron homeostasis, proteolysis, inflammation, protein folding, protease inhibition, adhesion, protein/RNA …

Modeling Of Monitoring Systems Of Solar Power Stations For Telecommunication Facilities Based On Wireless Nets, Ilkhomjon Xakimovich Siddikov, Khalimjon Ergashevich Khujamatov, Doston Turayevich Khasanov, Ernazar Nurjamiyevich Reypnazarov

Chemical Technology, Control and Management

In this paper described of modelling processes of the real-time remote monitoring system of solar power sources, modelled and investigated by wireless sensor nets of telecommunications devices. As a modelling environment was obtained Proteus software. In processes of modelling of the system, structure and a block diagram of the system were developed, each of elements is deleted to parts of the system and separately described. Specially created software for the research system. The structure of the system developed and software tested by modelling processes. The results of modelling of monitoring system presented in a virtual terminal, an oscillography, and a …

Nonlinear Dimensionality Reduction For The Thermodynamics Of Small Clusters Of Particles, Aditya Dendukuri

Graduate Theses and Dissertations

This work employs tools and methods from computer science to study clusters comprising a small number N of interacting particles, which are of interest in science, engineering, and nanotechnology. Specifically, the thermodynamics of such clusters is studied using techniques from spectral graph theory (SGT) and machine learning (ML). SGT is used to define the structure of the clusters and ML is used on ensembles of cluster configurations to detect state variables that can be used to model the thermodynamic properties of the system. While the most fundamental description of a cluster is in 3N dimensions, i.e., the Cartesian coordinates of …

Synthesis Of Polyurethane Incorporated By Calcium Oxide And Magnesium Oxide For Heavy Metal Removal From Water, Fard Mohsen Vafaei

Student Works (2020-2029)

Water contaminated by heavy metals such as copper, lead, nickel, and cadmium has significant adverse impacts on receiving water. In recent years, various methods, such as adsorption, chemical precipitation, and ion exchange, have been extensively studied for the elimination of heavy metals. Adsorption is one of the numerously and diversely reported mechanisms of removing heavy metals due to its simplicity and costeffectiveness. In this study, highly permeable rigid polyurethanes (PU) incorporating calcium oxide (CaO) (PU/CaO) composite materials were prepared via a facile and economic one-pot synthesis method and characterized for remediation of heavy metal from water. To investigate the effect …

Syntheses, Characterisations And Electrochemical Studies Of Nickel(Ii) And Cobalt(Ii)-Ligand Assisted Cooperative Complexes, Subramaniam Jeevithra Dewi

Student Works (2020-2029)

A newly designed tetradentate ligand L1 (L1 = 3,6-bis(pyrazol-1-yl)-pyridazine) which offers multinucleation sites on its moiety structure has been prepared. The reaction of L1 with different molar ratio of nickel and cobalt salts lead to the formation of di- and tetranuclear complexes [NiII 2(L1)2(CH3CN)4](PF6)4 (1), [NiII 4(L1)4(μ-OH)4](ClO4)4 (2) and [CoII/III(L1)4(μ-CH3O)2(μ-O)2](PF6)3(NO3) (3), which served as the attempt to design of catalysts based on cheap and earth-abundant metals for carbon dioxide reduction. The presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as the base controls the nuclearity of the complex formation. In the absence of DBU, complex 1 was formed in dinuclear fashion whereas complex 2 …

Preparations Of Nano-MnoX/Ti Electrocatalytic Membrane Electrode For Catalytic Oxidation Of Cyclohexane Using Intermittent Electrodeposition, Xue Zhou, Hong Wang, Zhen Yin, Yu-Jun Zhang, Jian-Xin Li

Journal of Electrochemistry

Cyclohexanone and cyclohexanol (KA oil) obtained from highly selective oxidation of cyclohexane (CHA) show important industrial value and application prospects. In this work, the intermittent electrodeposition was developed to prepare nano-MnO_x catalyst loading porous tubular titanium membrane electrode (MnO_x/Ti), which was employed to constitute an electro-catalytic membrane reactor (ECMR) for the oxidation of cyclohexane to produce cyclohexanol and cyclohexanone. The surface morphology, crystal structure and electrochemical property of the catalysts were characterized by FESEM, XRD and electrochemical workstation, respectively. The results show that the catalyst prepared by the intermittent electrodeposition displayed nano-flower-like γ-MnO₂. Compared with …

Preparation Of Α-Hydroxylated Acetal From 2-Butanone By Indirect Electrooxidation, Hai-Qing Huang, Ye Miao, Xin-Sheng Zhang

Journal of Electrochemistry

Acetoin (3-hydroxy-2-butanone) is an important food spice. As a platform compound, it is widely used in medicine, tobacco, cosmetics, chemical material and other industries. In this paper, α-hydroxylated acetal, an intermediate of acetoin, was prepared from 2-butanone by indirect electrooxidation in the plate and frame electrolytic cell, in which graphite plates were used as both an anode and a cathode, while KOH as an electrolyte and KI as a catalyst. Acetoin could be prepared by hydrolysis in acidic aqueous solution from acetoin intermediate. The effects of current density, electrolyte flow rate between the plates, 2-butanone concentration and electrolysis temperature …

Electrochemical Oxidation Of Metal Chromium In Odium Hydroxide Aqueous Solution, Ping Han, Hai-Tao Feng, Ya-Ping Dong, Sen Tian, Bo Zhang, Wu Li

Journal of Electrochemistry

Ferrochrome electrolysis technology is a novel method for preparing sodium chromate (Na₂CrO₄). Although the method performs well at soft reaction conditions, controllable process, environmentally friendly production process, etc., the electrochemical oxidation process of metal chromium in NaOH aqueous electrolyte is still unclear. At present, there are few research articles about specific electrochemical oxidation of metal chromium in NaOH aqueous electrolyte. It is, therefore, meaningful to carry out the research in electrochemical oxidation mechanism of chromium. The electrochemical oxidation of metal chromium in 0.01 mol·L^-1 ~ 10 mol·L^-1 NaOH aqueous electrolytes at 20 °C was …

Poly(Ethylene Oxide) Based Polymer Electrolytes For All-Solid-State Li-S Batteries, Xue Li, Zheng-Liang Gong

Journal of Electrochemistry

In recent years, research on lithium-sulfur (Li-S) batteries has received much attention because the sulfur positive electrode and the lithium metal negative electrode produce a high theoretical specific capacity (lithium metal ~ 3800 mAh·g^-1, sulfur ~ 1675 mAh·g^-1). In addition, sulfur is considered to be the most promising cathode material for secondary lithium batteries, due to its advantages of low price and environmental friendly. However, the practical application of conventional liquid Li-S batteries is still obstructed by several critical issues, such as lithium ploysulfides shuttle effect, long-term stability of lithium metal anode with organic liquid electrolytes, …

Synthesis And Raman Study Of Hollow Core-Shell Ni1.2Co0.8P@N-C As An Anode Material For Sodium-Ion Batteries, Jia-Hui Chen, Xiao-Bin Zhong, Chao He, Xiao-Xiao Wang, Qing-Chi Xu, Jian-Feng Li

Journal of Electrochemistry

With the increasing demand for large-scale energy storage, great progress has been made in discovering new advanced energy storage materials. Sodium-ion batteries (SIBs) have attracted much attention in recent years due to their use of abundant sodium resources and their comparable electrochemical capacity to lithium-ion batteries (LIBs). In this paper, we developed novel hollow core-shell Ni-Co bimetallic phosphide nanocubes with N-doped carbon coatings (Ni_1.2Co_0.8P@N-C) as the anode material for SIBs. The material was synthesized through a low-temperature phosphorization method using resorcinol formaldehyde (RF) resin coating with a Ni-Co Prussian blue analogue (PBA) as a template and …

Stability Studies For A Membrane Electrode Assembly Type Co2 Electro-Reduction Electrolytic Cell, Qing Mao, Bing-Yu Li, Wei-Yun Jing, Jian Zhao, Song Liu, Yan-Qiang Huang, Zhao-Long Du

Journal of Electrochemistry

Electro-catalytic reduction is an efficient way to achieve resourcable transformation of CO₂, which is one of the important techniques to solve the global environmental problems originated from excessive CO₂ emission. In this study, a membrane electrode assembly(MEA) type CO₂ electro-reduction electrolytic cell was constucted, which enables CO₂ feeding and real-time KHCO₃ aqueous updating on both sides of the cathode gas diffusion electrode (GDE). By means of the electrolytic cell, effects of KHCO₃ concentration and updating inside the liquid electrolytic chamber on CO₂ electro-reduction activity, production distribution and stability were investigated. The experimental …

Effects Of Temperature And Antioxidants On The Oxidation Of Biodiesel Derived From Waste Vegetable Oil, Randy L. Maglinao, Torrey J. Wagner, Keegan Duff

Faculty Publications

Biodiesel offers several environmental benefits and improvements to some fuel performance properties, but its poor oxidative stability has been a major concern. Currently, the accepted practice to improve biodiesel oxidative stability is the addition of antioxidants; numerous antioxidants have been studied but their effectiveness in inhibiting biodiesel oxidation is difficult to predict due to variation with resonance stability, solubility, reactivity, and volatility. To improve prediction efforts, this study explored the Rapid Small-Scale Oxidation Test (RSSOT) as a means to investigate how biodiesel oxidation is affected by antioxidant concentration and temperature, and compared its results with the oxidative stability index test. …

Catalytic Esterification Of Palm-Based Lauric Acid Diethylene Glycol Via Microwave Heating, Abas Noor Azeerah

Student Works (2020-2029)

Diethylene glycol esters of fatty acids are mixtures of diethylene glycol mono- and di-esters of saturated and unsaturated fatty acids derived from edible oils and fats. The products are produced either by direct esterification of diethylene glycol with fatty acids or by transesterification of diethylene glycol with oils or fats. This study involved in maximizing the conversion of lauric acid to glycol ester via esterification with diethylene glycol, aided by calcined Zn-Mg-Al catalyst in a 250-ml reactor using both conventional and microwave heating. Preliminary catalytic screening involving tin (II) oxalate, Amberlyst-15 and calcined Zn-Mg-Al catalysts in esterification of lauric acid …

Semi-Lagrangian Implicit Bhatnagar-Gross-Krook Collision Model For The Finite-Volume Discrete Boltzmann Method, Leitao Chen, Sauro Succi, Xiaofeng Cai, Laura Schaefer

Publications

In order to increase the accuracy of temporal solutions, reduce the computational cost of time marching, and improve the stability associated with collisions for the finite-volume discrete Boltzmann method, an advanced implicit Bhatnagar-Gross-Krook (BGK) collision model using a semi-Lagrangian approach is proposed in this paper. Unlike existing models, in which the implicit BGK collision is resolved either by a temporal extrapolation or by a variable transformation, the proposed model removes the implicitness by tracing the particle distribution functions (PDFs) back in time along their characteristic paths during the collision process. An interpolation scheme is needed to evaluate the PDFs at …

Synthesis Of Eco-Friendly Nanofluids For Enhancement Of Heat Transfer And Application In Different Flow Configuration Passages, Khan Asif

Student Works (2020-2029)

Since the invention of the heat exchangers, the working fluids such as water, ethyl glycol, oil and many others were used, however, they reveal relatively low thermal conductivity. Eco-friendly nanofluids and the cost-effective annular heat exchangers were introduced in this research to overcome the problem. In the present work, heat transfer coefficient and friction loss analyses of (TiO2 and GNP) water-based nanofluids were compared with DI-water flowing in annular conduit under turbulent flow regime. The nanoparticle weight concentrations of 0.1, 0.075, 0.05 and 0.025 wt.% were prepared by using a simple two-step method. The DI-water simulations were conducted by using …

Study Of Heat And Momentum Transfer To Colloidal Suspensions In Annular Closed Conduit Flow, Sadik Shoaib

Student Works (2020-2029)

With the advancement of science and the rapid growth of industries and the improved lifestyles of people, energy consumption has been increasing. Whereas the exploration of energy remained at a slower pace and the energy reservoirs are extinguishing at a faster rate. High energy consumption is also encouraging environmental pollution and global warming. Considering all these issues, scientists and engineers are desperately exploring highly efficient heat exchangers for the conservation of energy and minimize its losses. The present research has focused on obtaining highly efficient heat exchangers. Lots of research have performed on the improvement of heat exchanger materials, alteration …

Stress-State And Injection-Rate Dependent Damage Processes During The Hydraulic Fracturing Of Granite, Gayani Sasendrika Gunarathna

Dissertations

Hydraulic fracturing is a well-stimulation technique that is employed in field applications, such as enhanced geothermal systems (EGS) and shale oil/gas extraction. This research experimentally investigates the effect of the state of stress and injection rate on the hydraulic fracturing processes. In addition, a displacement discontinuity method (DDM) code, FROCK, is used to model the crack initiation and propagation in a granite specimen under hydraulic fracturing conditions. In order to conduct the experimental work, a test setup capable of applying a triaxial state of stress and water pressure inside pre-fabricated flaws cut in prismatic granite specimens is developed. Additionally, the …

Calculating Elastic Properties Of Confined Simple Fluids, Christopher D. Dobrzanski

Dissertations

Confinement in nanoporous materials is known to affect many properties of the fluids confined within their pores. The elastic properties are no exception. This dissertation begins with an overview of the relevant literature on ways of obtaining elastic properties of confined fluids. It outlines some fundamental gaps in our understanding. The chapters following address some of these gaps in understanding elastic properties of the confined fluid, in particular, how the shape of the confining pore matters, how supercriticality effects the properties, how an equation of state designed for confined fluids can be used to calculate elastic properties, and if an …

Chemistry Of Nanoscale Solids And Organic Matter In Sustainable Water Management Systems, Xuanhao Wu

McKelvey School of Engineering Graduate Student Theses & Dissertations

To alleviate global water scarcity and improve public health, engineered water treatment and management systems have been developed for purifying contaminated water and desalinating brackish or ocean water. These engineered systems provide substantial amounts of potable water and lessen environmental concerns about the release of contaminated water. Wastewater treatment plants (WWTPs), water desalination plants (WDPs), and managed aquifer recharge systems (MARs) are three representative sustainable water management (SWM) systems. But the operation of all three poses two fundamental questions: (1) What is the fate of nanoscale solids (e.g., engineered nanomaterials, naturally occurring nanoparticles) in SWM systems and how will their …

Green Synthesis Of Reduced Graphene Oxide For Efficient Adsorption-Photocatalysis Studies In Methylene Blue Dye Degradation, Ling Er Valerie Siong

Student Works (2020-2029)

Dyes are one of the major components of industrial effluents. Owing to the complex structures of these toxic organic compounds, the removal of dyes from effluents possesses a great challenge in wastewater treatment. In order to tackle this issue, one of the effective methods is to remove dyes via the combination of adsorption and photocatalysis processes. In the present work, reduced graphene oxide (rGO) was fabricated from graphene oxide (GO) by using an environmentally friendly solvothermal approach, whereby ethanol was employed as a non-toxic reductant. In order to investigate the formation of rGO, the reduction of GO was carried out …