Chemical Engineering Commons^™

Synthesis Of Aromatic Acetylene Alcohols Using Complex Catalytic Systems, Odiljon Ziyadullaev, Guzal Otamukhamedova, Abduvakhab Ikramov, Saida Abdurakhmanova, Otabek Boytemirov

CHEMISTRY AND CHEMICAL ENGINEERING

Some cyclic ketones (cyclopentanone, cyclohexanone, 2-methylcyclohexanone, menthol, camphor and adamantanone) enantioselective alkynylation reactions with phenylacetylene have been studied in the presence of complex catalytic systems - Zn(OTf)₂/NЕt₃/MeCN, 3,3′-Ph₂BINOL-2Li/TGF and BuLi/KO^tBu/TGF. Synthesis were performed new aromatic acetylene alcohols – 1-(2-phenylathinyl) cyclopentanol (1), 1-(2-phenylethinyl)cyclohexanol (2), 2-methyl-1-(2-phenylethinyl)cyclohexanol (3), 2-isopropyl-5-methyl-1-(2-phenylethinyl)cyclohexanol (4), 1,7,7,-trimethyl-2-(2-phenylethinyl)bicyclo [2.2.1] heptanol-2 (5) and 2-phenylethinyltricyclo [3,3,1.0^3,7]nonanol-2 (6). Synthesis reactions of aromatic acetylene alcohols, activation energies were determined, kinetic of chemical changes and reaction mechanisms were proposed. The course of the reactions and the effect of the selected ketone molecule size, structure and …

Heterogeneous Catalytic Conversions Of Acetylene, Abduvakhab Ikramov, Sevara Kholikova, Noryigit Musulmanov

CHEMISTRY AND CHEMICAL ENGINEERING

The reactions of interaction of acetylene with water vapor, acetic acid and ammonia in the presence of heterogeneous catalysts have investigated. Depending on the nature of the starting components used, acetaldehyde and acetone, vinyl acetate, pyridine bases and pyrrole synthesized. Heterogeneous catalysts selected for each studied reaction based on some scientific prerequisites for the selection of catalysts. Active catalysts for the investigated reactions were determined, which contain compounds of cadmium, zinc, bismuth, chromium, iron and copper, in general, d-group metals. γ-Al₂O₃, bentonite and kaolin used as a catalyst carrier. Hydrofluoric acid, acetic acid, ammonium fluoride and …

Economic Feasibility Of A Methanol To Dimethyl Ether Production Process To Avoid Contract Failure Shortfalls From The Covid-19 Pandemic, Jacob Noll, Robert Wasson, Harrison Mckinnis

Honors Theses

Our team entered the 2021 AVEVA Academic Competition, where teams of undergraduate senior chemical engineering students competed across the country. The competition was composed of two parts: the base case design and the optimization of a chemical process. As part of the competition, our team is acting as the Engineering team for a fictional company that has given us this project. Due to COVID-19, our methanol producing company has lost a contract with a customer, leaving 23,000 tonnes/yr of unclaimed methanol. We have two choices with this methanol: either sell the methanol on the market at the spot price for …

Ethylbenzene Production Case Study And Optimization, Brandon Borek

Honors Theses

The objective of this project was to investigate the process of producing ethylbenzene from the liquid-phase reaction of ethylene and benzene and perform parametric and topological optimizations to increase the net present value of the production facility. To do so, the base case conditions of the process were modeled and quantified economically followed by an investigation into the existing process to determine conditions that could be altered to improve the economic viability of the project. After optimizing the parametric conditions and topology of the process, the net present value of the project was increased by 305 million dollars to 191 …

Design And Analysis Of A Process To Convert Methanol Into Dimethyl Ether, Elisa M. White

Honors Theses

A recent economic downturn led to the loss of a contract for a company that sells methanol. The company has two options to recover some of the profit lost from the contract termination. One option is to sell the excess methanol at the spot market price, and the second option is to implement a process to convert the excess methanol into dimethyl ether. This project investigated the implementation of a process to convert the methanol from the lost contract into dimethyl ether. The process was simulated in AVEVA Process Simulation to estimate the size of equipment needed. A toller provided …

Design Of An Undergraduate Laboratory Experiment Utilizing A Stirred-Tank, Jacketed Bioreactor, Brennen Middleton

Honors Theses

Bioreactors are utilized in many industries, such as the food, alternative fuel, and pharmaceutical industries, to design and manufacture products. Unlike the similar chemical batch reactors utilized in many chemical processing facilities, bioreactor utilization requires engineers to consider a wider range of operating conditions and parameters. This results in a more complex reaction system and controls network. Due to this, it is imperative for chemical and biomedical engineering students to not only understand the theory surrounding these reactor systems, but also understand how to properly design and perform operating procedures with these systems. Thus, it was determined to create an …

Investigative Study Of Microalgal And Electrochemical Wastewater Treatment Systems And Modeling Of The Wafer-Enhanced Electrodeionization Using Supervised Learning, Humeyra Betul Ulusoy Erol

Graduate Theses and Dissertations

Wastewater has a serious impact on environment and public health due to its high concentration of nutrients and toxic contaminants. Without proper treatment, excess nutrients discharged in wastewater can cause a damage to the ecosystem such as undesirable pH shifts, cyanotoxin production, and low dissolved oxygen concentrations.

Main objectives of this dissertation work were to investigate i) the biofuel potential of P. cruentum when grown in swine wastewater, ii) the influence of four most commonly used ion exchange resins on the system efficiency and selectivity for the removal of sodium, calcium, and magnesium ions, and iii) the modeling of wafer-enhanced …

Pd-Based Electrocatalysts For Oxygen Reduction And Ethanol Oxidation Reactions: Some Recent Insights Into Structures And Mechanisms, Zhi-Peng Wu, Chuan-Jian Zhong

Journal of Electrochemistry

The development of efficient electrocatalysts for applications in fuel cells, including proton-exchange membrane fuel cell (PEMFC) and direct ethanol fuel cell (DEFC), has attracted extensive research attention in recent years. Oxygen reduction reaction and ethanol oxidation reaction are two of the key reactions where the design of active, stable and low-cost electrocatalysts is critical for the mass commercializations of PEMFCs and DEFCs. This challenge stems largely from the limited understanding of the catalyst structures and reaction mechanisms. Progress has been made in investigations of electrocatalysts derived from Pd-based alloy nanomaterials both experimentally and computationally. We highlight herein some of the …

Theoretical Studies Of Metal-N-C For Oxygen Reduction And Hydrogen Evolution Reactions In Acid And Alkaline Solutions, Xue-Ping Qin, Shang-Qian Zhu, Lu-Lu Zhang, Shu-Hui Sun, Min-Hua Shao

Journal of Electrochemistry

Single atom catalysts (SAC) have been regarded as the promising alternatives to platinum group metals due to their low costs and potentially high catalytic activities in various electrocatalytic reactions. The atomic mechanism understanding of activity discrepancy among different metal and nitrogen co-doped carbon-based catalysts is still lacking. Here, non-precious metal and nitrogen co-doped carbons (Me-N-C, Me = Fe and Co) as the model catalysts are investigated by combining experimental and theoretical studies to explore the catalytic activities and corresponding reaction mechanisms toward oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) at universal pHs. Atomic theoretical simulations suggest that Fe-N-C …

Oxygen-Exposure Induced Rapid Oxidation Of Spiro-Ometad In Cspbibr2 Perovskite Solar Cells, Wei-Guo Wang, Tian Bai, Gao-Fei Xue, Mei-Dan Ye

Journal of Electrochemistry

2,2′,7,7′-tetrakis(N,N-di-p-methoxyphenyl-amine)-9,9′-spirobifluorene (Spiro-OMeTAD) is the most widely used hole transport material in perovskite solar cells (PSCs). However, its oxidation in the air takes a long time and results in the attack of perovskite by water. In this regard, we performed the oxidation process of Spiro-OMeTAD in oxygen, where perovskite can be protected from water, guaranteeing the integrity of perovskite. It was demonstrated that the champion Spiro-OMeTAD based CsPbIBr₂ PSCs after oxygen oxidation achieved a 7.19% power conversion efficiency (PCE), showing a higher PCE than 6.29% of the champion device oxidized in air. A series of electrochemical characterization methods were applied …

Application Of Atomically Precise Metal Nanoclusters In Electrocatalysis, Zhi-Hua Zhuang, Wei Chen

Journal of Electrochemistry

Metal nanoclusters (M NCs) consist of only several to a few hundred of metal atoms and possess core sizes less than 2 nm. Owing to the quantum size effect, the electronic states of M NCs evolve to discrete levels similar to the molecule energy gaps, other than a continuous density of states to produce plasmon characteristic of bulk metal nanoparticles (M NPs). In comparison with the conventional M NPs, M NCs exhibit dramatically unique electronic and optical properties, such as molecule-like energy gaps, strong photoluminescence and high catalytic properties, which make them promising for potential application in numerous fields, such …

Synthesis Of Some N-Oxides Of Pyridylacethylene Amines Based On 2-Methyl-5-Ethynylpyridine, Abduvakhab Ikramov, Odiljon Ziyadullayev, Adkham Khamidjanov, Shavkat Bojariev, Davron Khandamov

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this work is to study the reaction of 2-methyl-5-ethynylpyridine N-oxide with some aliphatic and aromatic amines to obtain N-oxides of pyridylacetylenic amines. 2-Methyl-5-ethylpyridine converted to 2-methyl-5-vinylpyridine by dehydrogenation, and 2-methyl-5-ethynylpyridine obtained by bromination and dehydrobromination. 2-methyl-5-ethynylpyridine N-oxide synthesized by oxidation of 2-methyl-5-ethynylpyridine with perhydrol in acetic anhydride. The synthesis of N-oxides of pyridylacetylenic amines by the Mannich reaction carried out. The effect of the solvents: methanol, ethanol and n-dioxane, the catalyst, and the reaction time on the yield of the final product studied. The structure and composition of the synthesized PAA N-oxides were established using IR and …

The Role Of Hydrogen Bonds In Diluted Ethanol Solutions Of Cyclohexane And Dimethylformamide, Dilbar Bozorova, Shukur Gofurov, Mavlonbek Ziyayev, Dildora Mirtojiyeva, Odina Ismanova, Oksana Ismoilova

CHEMISTRY AND CHEMICAL ENGINEERING

The refractometric method and Fourier transform infrared spectroscopy were used to determine the optical features of the concentration characteristics of diluted ethanol solutions of cyclohexane and dimethylformamide. It was found for the first time that at some concentrations the hydrogen bond is stronger than for a pure ethanol solution. The first maximum of the excess refractive index of solutions is formed at a concentration of 0.02 mole fraction of cyclohexane and dimethylformamide, which is in good correlation with IR spectroscopy, indicating the largest number of formed hydrogen bonds.

Gold-Semiconductor Photocatalysts For Water Treatment Under Visible And Ultraviolet Light, Daniel Willis

LSU Doctoral Dissertations

Water scarcity threatens the lives of millions of people worldwide. It is imperative to improve the energy efficiency and affordability of water treatment methods to avoid a looming water-energy crisis. To meet this challenge, I have pursued research on the use of sunlight—our most reliable and abundant source of energy—to drive water treatment through photocatalysis. I explored the literature and found gold-semiconductor materials to hold promise for harvesting sunlight and catalyzing the breakdown of waterborne contaminants. Initially, I designed a novel optical cavity with gold (Au) nanoparticles on a zinc oxide / titania (TiO₂) / aluminum film stack …

Abiotic Sensor For Electrochemical Determination Of Chlorpyrifos In Natural Water Based On The Inhibition Of Silver Nanoparticles Oxidation, Ziad Khalifa, Moustafa Zahran, Magdy Zahran, Magdi Abdelazzem

Chemical Engineering

Chlorpyrifos, organophosphorus pesticide, is a persistent organic pollutant that may cause serious health problems. Herein, a simple, green, and sensitive electrochemical inhibition sensor based on silver nanoparticles (AgNP)-modified glassy carbon (GC) electrode was developed for the determination of chlorpyrifos in natural water for the first time. The chemical reduction technique based on natural reducing and capping agents such as dissolved organic matter (DOM), natural latex (NL) and mucilage was employed for AgNP synthesis. DOM-AgNP, NL-AgNP, and Mucilage-AgNP were immobilized on GC by sticking technique under the same voltammetric and electrolytic conditions. The oxidation behavior of the three modified electrodes was …

Preparation Of Pdcoir Tetrahedron Nanocatalysts And Its Performance Toward Ethanol Oxidation Reaction, Zhi-Yuan Yu, Rui Huang, Jie Liu, Guang Li, Qian-Tong Song, Shi-Gang Sun

Journal of Electrochemistry

As a new energy conversion device, direct ethanol fuel cells (DEFCs) are widely concerned because of their remarkable advantages such as high theoretical energy density and wide fuel sources. However, the rapid development of DEFCs has been severely impeded due to the sluggish kinetic process and toxic intermediates especially in their anodic reactions. Palladium (Pd)-based materials are considered to be excellent anode catalysts for DEFCs, especially under alkaline conditions. And further improving their performance is an important direction to promote the development of DEFCs. Surface structure and composition are the key factors affecting the performance of catalysts which can be …

Research Progress In Electrodeposition Technology Of Titanium-Based Iridium Oxide Electrode, Dan-Dan Wu, Xu Wu

Journal of Electrochemistry

Titanium-based iridium oxide electrode has been widely used in various fields, such as electrocatalytic oxidation, biomedical applications, hydrometallurgical metal recovery, electro-osmotic dewatering, etc. At present, it is mainly prepared by traditional thermal decomposition method, however, which has high cost, cumbersome process, mainly relying on manual labor and cannot be mass-produced yet. It is, therefore, urgently necessary to explore new preparation technologies by focusing on electrodeposition technology, with technological characteristics such as eco-friendly and sustainable development. This article systematically discusses the research progress in iridium oxide electrodeposition preparation technology from the aspects of deposition solution formulation, base material selection and treatment, …

Preparations And Electrocatalytic Ethanol Properties Of Palladium Intercalated Hydrotalcite, Shou-Xun Hu, Liang Li, Jun-Hao Yang, Liu-Qiang Li, Zhi-Hao Jin

Journal of Electrochemistry

High-performance electrocatalysts play a vital role in the commercial application of direct fuel cells. Current anode materials still have such problems as low activity, easy poisoning and high cost. In this study, a new type of nano- palladium (Pd) catalyst was prepared by dipping method using layered double hydroxides (LDHs) as the carrier. X-ray diffractometer, scanning electron microscope (SEM), inductively coupled plasma mass spectrometer (ICP-MS), energy spectrometer, transmission electron microscope (TEM), cyclic voltammetry, chronoamperometry and electrochemical impedance spectroscope were used to analyze the structure and electrocatalytic performance of the catalyst. The results showed that the newly prepared Pd/Mg-Al-LDHs still maintained …

Syntheses Of Na3V2(Po4)2O2F As A Cathode For Sodium Ion Battery Application, Kai Wu

Journal of Electrochemistry

High-temperature solid-state method, hydro-thermal method and solvo-thermal method have been mainly employed to synthesize Na₃V₂(PO₄)₂O₂F (NVPF) cathode materials. However, these methods are energy consuming and complicated, which is not applicable for a large scale industrial production. In this study, a rather low-temperature (70℃) co-precipitation strategy was proposed to synthesize NVPF cathode materials. The as-prepared NVPF cathode materials showed a spherical shape with a diameter of 400 ~ 500 nm, and exhibited a sodium storage of 105.6 mAh·g^-1 and an efficiency of 90.06%. After a simple thermal process, the specific …

Ethinylation Reactions Of Some Aldehydes In The Presence Of Phenylacetylene Using High-Base Catalytic Systems, Abdurakhmanova Saida, Ikramov Abduvaxab, Ziyadullayev Odiljon, Ablakulov Lochin

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the research work is the development of synthesis methods of aromatic acetylene alcohols and their various derivatives using different catalytic systems and also, determining their structure, physico-chemical and biological properties. The most effective way of synthesizing AAA is determined using selected complex catalytic systems and also, the range of catalytic activity of used catalysts is created. Acetic aldehyde, benzaldehyde and cyclohexonal, high-base catalytic systems − MOH/ДМСО∙H2O and M2CO3/ДMСO∙H2O with phenylacetylene reaction of enantioselective etynilation were investiged. Efficiency and course of chemical reaction in the process of formation acetylene alcohol affection of temperature, reaction duration, solvents, catalysts and …

Synthesis Of Meta-Altered Arylmaleinamide And Preparation Of Esters In Their Presence, Turaeva Khurshida, Yuldasheva Mukhabbat, Khaydarova Sadokat

CHEMISTRY AND CHEMICAL ENGINEERING

The development of new methods of synthesis using cheaper reagents for the preparation of maleic acid derivatives, the study of chemical properties and the determination of new directions for the practical application of maleic acid derivatives are still relevant. Therefore, the development of this work is an urgent task. The aim of this study was to obtain the synthesis of monomaleinamide compounds under various conditions to obtain arylmaleimide derivatives of maleic acid and to transfer them in a pure state for further reactions. In this study, scientific studies were carried out to find convenient methods for the preparation of monoamide …

Assessment Of Heavy Metal Concentration In Soils Around Geita The Gold Mine, Tanzania, Mariam G. Mgendi, Mkabwa L. K Manoko, W.J.S. Mwegoha, C. Southway C. Southway

Journal of Humanities and Social Sciences

Health issues related to gold mining cannot be underestimated. Gold mining produce acid mine drainage (AMD), which in turn releases heavy metals into the nearby environment, hence causing environmental pollution. Heavy metals are naturally very toxic, thus pose a great health concern especially when their concentration exceeds the recommended permissible limits. In this study, concentrations of five heavy metals—including Pb, Ni, Cr, Cu and Zn—were assessed in the soil around Geita Gold Mine (GGM). A total of 17 sampling sites were established from which the soil samples were collected at 0-15cm and 15-30cm soil depth. The concentration of both total …

New Mechanism Insight For The Hydrogenation Of Co/Co2 Gas Mixtures To Hydrocarbons Over Iron-Based Catalyst, Sandeep Badoga, Michela Martinelli, Muthu Kumaran Gnanamani, Young Koh, Wilson D. Shafer

Center for Applied Energy Research Faculty and Staff Publications

Iron-based catalysts are the most suitable candidates for converting CO₂ or CO₂-rich syngas to hydrocarbons. However, several issues about the mechanism of CO₂ hydrogenation are still unclear. In this work, we investigated the performance of an iron-based catalyst with H₂/CO₂, H₂/CO/N₂ and H₂/CO/¹³CO₂/N₂ gas mixtures at the same process conditions (T = 270°C, P = 175 psi and SV = 3 NL/h/g_cat). The CO₂ hydrogenation rate was much lower than that observed for CO hydrogenation. ¹³CO_{2 …}

Valorization Of Xylan In Agroforestry Waste Streams, Harrison Appiah

Graduate Theses, Dissertations, and Problem Reports (ETD)

Valorization of Xylan in Agroforestry Waste Streams.

Harrison Appiah

Microwave-assisted deep eutectic solvent and gamma-valerolactone metallic chloride catalyzed conversion of xylan to furfural were investigated using a 2x3 factorial experimental design at two levels of percent microwave power, reaction time, and catalyst concentration. The levels of each factor studied were (20%, 60% microwave power, 2, 4 minutes, and 10, 20mg) respectively. The effect of three metallic chloride catalysts (LiCl, FeCl3.6H20, CuCl2) on the conversion of xylan to furfural was also investigated. The gamma-valerolactone-ferric chloride sent system exhibited the highest mean yield of furfural (56.50%). The next highest furfural yield of …

Biological Conversion Of Carbon Dioxide To Value-Added Chemicals, Owen James Mcgrath

Graduate Theses, Dissertations, and Problem Reports (ETD)

As Carbon Dioxide (CO₂) levels in the atmosphere continue to rise due to human intervention, there is increased urgency to take actions to mitigate the potential ramifications. Many countries have instituted a CO₂ tax and have provided funding to finding potential solutions to our growing CO₂ problem. Further investigating CO₂ capture, sequestration, and utilization is key to combating rising CO₂ levels and methods being investigated have increased substantially in recent years. Converting CO₂ into fuels and value-added chemicals provides a unique opportunity to create materials of value from a substance that is being …

Improving Performance And Durability Of Intermediate Temperature Proton‐Conducting Solid Oxide Electrolysis Cells Via Materials Design And Catalyst Surface Engineering, Hanchen Tian

Graduate Theses, Dissertations, and Problem Reports (ETD)

Solid oxide steam electrolysis cell, a promising electrical-chemical conversion device for the next generation efficient hydrogen production and energy storage, has been actively studied because of their high energy conversion efficiencies and prospective applications as electrochemical reactors. After decades of research on protonic ceramic materials, remarkable advances have been made in the protonic ceramic electrochemical cells (PCECs) air electrode and electrolyte. However, the existing air electrodes are far from satisfying the requirements of practical applications, a series of issues, including the lack of active and durable electrodes, greatly limit the commercialization. To date, the systematic development of triple conducting catalysts …

Effects Of Microporous Structure On The Enzymatic Conversion Of Biomass Using A Multiscale Model, Saketh Merugu

Dissertations, Master's Theses and Master's Reports

The generation of biofuels from lignocellulosic biomass involves innovative process technology that is being investigated worldwide. Enzymatic hydrolysis is a major step in the contemporary process of the generation of biofuels. Guided by pore size distribution measured using NMR cryoporometry, we developed pore-enzyme diffusion and adsorption models at the particle level coupled with a kinetic model for cellulose, cellobiose, and glucose production at flask level. By simulating these models in MATLAB, COMSOL, and Polymath software packages, we investigate the effects of various biomass particle-related parameters (particle dimensions, porosity, enzyme accessibility) on the characteristic time of enzyme diffusion and adsorption and …

Cold Plasma Enhanced Active Sites On Supported Nip Nanoparticles For The Oxygen Evolution Reaction, Michael Ricci

Williams Honors College, Honors Research Projects

Identifying materials to efficiently facilitate the oxygen evolution reaction (OER) is key to advancing water electrolysis, an essential technology in the pathway towards a sustainable energy future. Here, we explore cold-plasma treatment as a facile method to enhance the activity of NiP nanoparticles supported on activated carbon. NiP nanoparticles were synthesized on an activated carbon support using a solid-state method and were then treated with argon, oxygen, and hydrogen plasmas for extended times. In all cases, plasma treatment reduced the number of active sites on the support. OER activity was evaluated by testing the materials in alkaline conditions. The activities …

Natural Gas Conversion To Value-Added Chemicals By Microwave Catalytic Processes, Brandon Robinson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ethane is the second-largest component in natural gas and is typically separated out to minimize condensation in the pipelines. The technical difficulties and cost associated with the transportation and the storage of ethane have led companies to start burning natural gas to produce power or flaring which attributes to the global CO₂ emission problem. The conversion of ethane to higher-value liquid products is of increasing importance so that the natural gas can be safely utilized and cost-effectively transported. Existing commercial technologies used to convert ethane to liquid chemical products are typically based on the indirect syngas route, such as …

Continuous Preparation And Application Of Novel Heterogeneous Catalysis, Michael B. Burkholder

Theses and Dissertations

Transition metal heterogeneous catalysts are widely used across many chemical industries to reduce waste and emissions and reduce production time while increasing rate. The prevalence of these materials results from the complex relationship between metal nanoparticles and supports affecting final catalytic performance. Rational catalyst synthesis describes the ability to precisely engineer structures through controlled preparation. Novel materials and continuous processing represent a promising approach for rational catalyst synthesis.

The application of these catalysts in continuous, multiphase processes, such as cross-coupling reactions, oxidation chemistry, and nitroreduction processes, are paramount to developing new commercial routes for high-value products. Pd/G catalysts synthesized by …