Chemical Engineering Commons^™

From Waste To Energy: The Electrochemical Reduction Of Co2 Using Recycled Nanostructured Catalysts, Ibrahim Badawy

Theses and Dissertations

The reduction of carbon dioxide (CO₂RR) using electrochemistry is a promising solution for the burgeoning global energy crisis. The overall vision of its implementation relies on renewable energy sources to power the reaction creating carbon neutral products and effectively closing the carbon cycle. Research in this field has come a long way since its inception in the mid-1900s. However, there remain significant hurdles and important considerations to overcome in order to reach full commercialization. Most electrocatalysts tested for CO₂RR have been designed solely for maximum performance while ignoring the environmental consequences if such a material were …

The Effect Of Heat Treatment And Chemical Treatment On Natural Fibre To The Durability Of Wood Plastic Composites – A Review, Nuratiqah Asyiqin Mohd Nasharudin, Nur Fatihah Sulaiman, Nurul Aziemah Mohammad, Wan Nor Raihan Wan Jaafar, Falah Abu Dr., Siti Norasmah Surip

Journal of Materials Exploration and Findings

The application of WPC is not only limited to indoor applications but has been extended to exterior applications where properties of WPC could compromise during service life. WPC was derived from wood fiber of various sizes to reinforce polymers. Wood fiber has the advantage of a cheaper price, being abundantly available, and ease of processing, however, the critical factor is its hydrophilic nature, where moisture absorption is likely to occur. Thus, treatments for reducing the hydrophilicity of wood fibers are applied. By treatment of wood fiber, the surface impurities were removed, leaving the roughened surface of fibers, thus providing a …

Freestanding Graphene Heat Engine Analyzed Using Stochastic Thermodynamics, J. Durbin, J. M. Mangum, M. N. Gikunda, F. Harerimana, P. Kumar, L. L. Bonilla, P. M. Thibado

Physics Faculty Publications and Presentations

We present an Ito-Langevin model for freestanding graphene connected to an electrical circuit. The graphene is treated as a Brownian particle in a double-well potential and is adjacent to a fixed electrode to form a variable capacitor. The capacitor is connected in series with a battery and a load resistor. The capacitor and resistor are given separate thermal reservoirs. We have solved the coupled Ito-Langevin equations for a broad range of temperature differences between the two reservoirs. Using ensemble averages, we report the rate of change in energy, heat, and work using stochastic thermodynamics. When the resistor is held at …

Product Costing And Pricing In Small And Medium Enterprises In Tanzania, Cosmas F Kindole

Tanzania Journal of Engineering and Technology (TJET)

metalwork small and medium enterprises located in Dar es Salaam with the aim of establishing methods used by SMEs in Tanzania in setting selling prices of their products. The study was necessitated by the apparent discrepancy of prices for similar products from SMEs. The approach used to gather information was mainly through direct interview and the use of questionnaires. Direct observation and literature review were also used to establish the whole costing and pricing practices in metal manufacturing SMEs. The findings of the study established that product selling practices of the surveyed SMEs were based on instinct and appearance of …

Hydrogen-Bonding Trends In A Bithiophene With 3- And/Or 4-Pyridyl Substituents, Alison M. Costello, Rebekah Duke, Stephanie Sorensen, Nadeesha Kothalawala, Moses Ogbaje, Nandini Sarkar, Doo Young Kim, Chad Risko, Sean Parkin, Aron J. Huckaba

UK CARES Faculty Publications

To improve the charge-carrier transport capabilities of thin-film organic materials, the intermolecular electronic couplings in the material should be maximized. Decreasing intermolecular distance while maintaining proper orbital overlap in highly conjugated aromatic molecules has so far been a successful way to increase electronic coupling. We attempted to decrease the intermolecular distance in this study by synthesizing cocrystals of simple benzoic acid coformers and dipyridyl-2,2′- bithiophene molecules to understand how the coformer identity and pyridine N atom placement affected solid-state properties. We found that with the 5-(3-pyridyl)-5′-(4-pyridyl)-isomer, the 4- pyridyl ring interacted with electrophiles and protons more strongly. Synthesized cocrystal powders …

Fate And Distribution Of Orally-Ingested Ceo2-Nanoparticles Based On A Mouse Model: Implication For Human Health, Xingmao Ma, Xiaoxuan Wang, Lei Xu, Honglan Shi, Hu Yang, Kerstin K. Landrock, Virender K. Sharma, Robert S. Chapkin

Chemistry Faculty Research & Creative Works

The use of nanoparticles in agrichemical formula and food products as additives has increased their chances of accumulation in humans via oral intake. Due to their potential toxicity, it is critical to understand their fate and distribution following oral intake. Cerium oxide nanoparticle (CeO2NP) is commonly used in agriculture and is highly stable in the environment. as such, it has been used as a model chemical to investigate nanoparticle's distribution and clearance. based on their estimated human exposure levels, 0.15–0.75 mg/kg body weight/day of CeO2NPs with different sizes and surface charges (30–50 nm with negative charge and <25 >nm with positive …

Molecular Simulations Of Mechanical Effects Of Adsorption In Gas And Liquid Phases, Alina Emelianova

Dissertations

Fluids adsorbing in nanoporous solids cause high pressures that affect the solids and the properties of the fluids themselves. This work explores the mechanical response of solids to the adsorption of gas and liquid. Chapter 1 outlines the current achievements in investigating the mechanical response of adsorbents to the adsorption process, specifically, the computational approaches to predict adsorption-induced deformation. Chapter 2 introduces the theoretical and computational methods employed in this work. Chapters 3-7 address the design and application of the computational techniques for such prediction in different systems: mesoporous silica, microporous zeolites, and metal-organic frameworks, and Chapter 8 focuses on …

P-Doped Ru-Pt Alloy Catalyst Toward High Performance Alkaline Hydrogen Evolution Reaction, Rong-Qin Huang, Wei-Ping Liao, Meng-Xuan Yan, Shi Liu, Yuan-Ming Li, Xiong-Wu Kang

Journal of Electrochemistry

Electrocatalytic water splitting represents grand promise for hydrogen fuel in modern energy equipment, and the design and fabrication of higher performance catalysts are at the central. Herein, we report the sequential phosphorus (P)-doping into ruthenium (Ru) nanoparticles (Ru-P/C) by thermal annealing of Ru nanoparticles in phosphine (PH₃) atmosphere and deposition of extremely low concentration of platinum (Pt) to obtain P-doped Ru-Pt alloy catalyst supported on carbon nanotubes (CNTs), which is denoted as (Ru-P)#Pt/C. The data by X-ray diffraction spectroscopy and transmission electron microscopy show that the Ru nanoparticles existed in the form of hexagonal close-packed (hcp) phase with …

Deep Euteceic Solvents-Assisted Synthesis Of Novel Network Nanostructures For Accelerating Formic Acid Electrooxidation, Jun-Ming Zhang, Xiao-Jie Zhang, Yao Chen, Ying-Jian Fan, You-Jun Fan, Jian-Feng Jia

Journal of Electrochemistry

Deep eutectic solvents (DESs) have been reported as a type of solvent for the controllable synthesis of metal nanostructures. Interestingly, flower-like palladium (Pd) nanoparticles composed of staggered nanosheets and nanospheres are spontaneously transformed into three-dimensional (3D) network nanostructures in choline chloride-urea DESs using ascorbic acid as a reducing agent. Systematic studies have been carried out to explore the formation mechanism, in which DESs itself acts as a solvent and soft template for the formation of 3D flower-like network nanostructures (FNNs). The amounts of hexadecyl trimethyl ammonium bromide and sodium hydroxide also play a crucial role in the anisotropic growth and …

Fe Nanoparticles Encapsulated In N-Doped Porous Carbon For Efficient Oxygen Reduction In Alkaline Media, Chun-Yan Li, Rui Zhang, Xiao-Jie Ba, Xiao-Le Jiang, Yao-Yue Yang

Journal of Electrochemistry

Rational design and synthesis of non-precious-metal catalyst plays an important role in improving the activity and stability for oxygen reduction reaction (ORR) but remains a major challenge. In this work, we used a facile approach to synthesize iron nanoparticles encapsulated in nitrogen-doped porous carbon materials (Fe@N-C) from functionalized metal-organic frameworks (MOFs, MET-6). Embedding Fe nanoparticles into the carbon skeleton increases the graphitization degree and the proportion of graphitic N as well as promotes the formation of mesopores in the catalyst. The Fe@N-C-30 catalyst showed the excellent ORR activity in alkaline solutions (E₀ = 0.97 V vs. RHE, E_{1/2 …}

Vitreoscilla Globin Promoter Cloning And Testing In Escherichia Coli, Lauren J. Coffey

Rose-Hulman Undergraduate Research Publications

No abstract provided.

Microwave Regeneration And Thermal And Oxidative Stability Of Imidazolium Cyanopyrrolide Ionic Liquid For Direct Air Capture Of Carbon Dioxide, Yun-Yang Lee, Eda Cagli, Aidan Klemm, Ruth Dikki

Faculty Scholarship

Understanding the oxidative and thermal degradation of CO2 sorbents is essential for assessing long-term sorbent stability in direct air capture (DAC). The potential degradation pathway of imidazolium cyanopyrrolide, an ionic liquid (IL) functionalized for superior CO2 capacity and selectivity, is evaluated under accelerated degradation conditions to elucidate the secondary reactions that can occur during repetitive absorption-desorption thermal-swing cycles. The combined analysis from various spectroscopic, chromatographic, and thermal gravimetric measurements indicated that radical and SN2 mechanisms in degradation are encouraged by the nucleophilicity of the anion. Thickening of the liquid and gas evolution are accompanied by 50 % reduction in CO2 …

Enhancing Compatibility And Mechanical Properties Of Natural Rubber Composites, Krisma Yessi Sianturi, Adam Febriyanto Nugraha, Belle Kristaura, Mochamad Chalid

Journal of Materials Exploration and Findings

Pure natural rubber (NR) exhibits low mechanical properties, necessitating the incorporation of additives like vulcanizing agents and fillers. Carbon black and silica, conventional fillers, are relatively expensive and not environmentally friendly. This study explores using Oil Palm Empty Fruit Bunch (OPEFB) fiber as an affordable, abundant, and biodegradable alternative filler for NR. However, compatibility issues arise between the nonpolar NR and the polar OPEFB fiber. A latex-starch hybrid coupling agent (CA (NR-St)) was added to the composite formulation to address this. NR, OPEFB fiber, and the coupling agent were mixed using an open roll mill with a 10 phr OPEFB …

Battery Design, Construction, And Characterization For Small Motor Use Focusing On Anodic Zinc For Electron Flow, Amber Veach

Chemical Engineering Undergraduate Honors Theses

This thesis explores the construction, characterization, and application of anodic zinc batteries for powering a small electric motor for the ChemE Car competition. Two zinc galvanic cell batteries were studied: zinc-carbon and zinc-air batteries. Prototype batteries were constructed and tested for voltage, amperage, and power production. In the zinc-carbon trials, a 3:1 mixture of manganese dioxide and graphite was determined to be the best cathode for power production. The size which allowed for sufficient power while maintaining the smallest footprint on the car was a zinc can six cm tall and two cm in diameter. Analysis of paper zinc-air battery …

Probing The Structure Of Water On Surfaces: From Water Absorption To Ice Nucleation, Jiarun Zhou

All Dissertations

Water, essential for all life forms, is the most abundant, simple, yet mysterious molecule in the world. This molecule, consisting of only three atoms, behaves in unexpectedly different ways with the change of environment. In the past, studies of water under different conditions (temperature, pressure, on the surfaces, with confinement) have been conducted using experimental and computational methods. However, the influence of a given environment on water properties is yet to be fully understood. This dissertation studies water at complex interfaces (surfaces with various chemistry and physics properties) in both the liquid and crystalline states. Various heterogeneous systems used to …

Repeated Low-Level Blast Exposure Alters Urinary And Serum Metabolites, Austin Sigler, Jiandong Wu, Annalise Pfaff, Olajide Adetunji, Paul Ki-Souk Nam, Donald James, Casey Burton, Honglan Shi

Chemistry Faculty Research & Creative Works

Repeated exposure to low-level blast overpressures can produce biological changes and clinical sequelae that resemble mild traumatic brain injury (TBI). While recent efforts have revealed several protein biomarkers for axonal injury during repetitive blast exposure, this study aims to explore potential small molecule biomarkers of brain injury during repeated blast exposure. This study evaluated a panel of ten small molecule metabolites involved in neurotransmission, oxidative stress, and energy metabolism in the urine and serum of military personnel (n = 27) conducting breacher training with repeated exposure to low-level blasts. The metabolites were analyzed using HPLC—tandem mass spectrometry, and the Wilcoxon …

Dual Crosslinked Poly(Acrylamide-Co-N-Vinylpyrrolidone) Microspheres With Re-Crosslinking Ability For Fossil Energy Recovery, Jingyang Pu, Baojun Bai, Jiaming Geng, Na Zhang, Thomas Schuman

Chemical and Biochemical Engineering Faculty Research & Creative Works

Microspheres have been proposed to be applied in controlling wastewater production for mature oilfields and migrating leakage for gas and nuclear waste storage. However, it remains challenging for stacked microspheres to maintain strong blocking ability in micron-sized small pores or fractures. in this study, a novel microsphere was developed with comprehensive properties including high deformability and long re-crosslinking time upon tunable swelling ratio for the applications. a dual covalent and physical crosslinking strategy was used to develop novel microspheres reinforced by a hydrogen bond (H-bond, between pyrrole ring and amide group) and coordination bond (between chromium acetate (CrAc) and carboxyl …

Dual Crosslinked Poly(Acrylamide-Co-N-Vinylpyrrolidone) Microspheres With Re-Crosslinking Ability For Fossil Energy Recovery, Jingyang Pu, Baojun Bai, Jiaming Geng, Na Zhang, Thomas P. Schuman

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Microspheres have been proposed to be applied in controlling wastewater production for mature oilfields and migrating leakage for gas and nuclear waste storage. However, it remains challenging for stacked microspheres to maintain strong blocking ability in micron-sized small pores or fractures. In this study, a novel microsphere was developed with comprehensive properties including high deformability and long re-crosslinking time upon tunable swelling ratio for the applications. A dual covalent and physical crosslinking strategy was used to develop novel microspheres reinforced by a hydrogen bond (H-bond, between pyrrole ring and amide group) and coordination bond (between chromium acetate (CrAc) and carboxyl …

Separation Of Organic Acids Through Direct Catalysis From Sugars, Katelyn Robinson

Chemical Engineering Undergraduate Honors Theses

Society relies on plastic products, whether they are single use or durable. A downside of plastic is that the most common type is a product of oil and oil is not only a limited resource but also a climate-damaging resource. Polylactic acid (PLA) is a bio-based, biodegradable plastic. However, the process of converting biomass to polylactic acid polymer has the largest environmental impact of the PLA production process, so alternative methods of conversion are needed (Moretti et al., 2021). The polylactic acid polymer can be made with lactic acid, which can be converted from glucose.

The Study Of Corrosion On Additive-Manufactured Metals., Braydan Daniels

Electronic Theses and Dissertations

The purpose of this study was to investigate and compare the corrosion mechanisms between wrought and additive-manufactured (3D-printed) copper and stainless steel. The experimental procedure consisted of measuring the open circuit potential, electrochemical impedance spectroscopy, linear sweep voltammetry, Tafel analysis, surface topology, and scanning electron microscopy for each metal within salt water, tap water, sulfuric acid, and synthetic body fluid (excluding copper in synthetic body fluid).

Overall, printed stainless steel was more corrosion-resistant than wrought stainless steel in tap water and synthetic body fluid based on OCP, LSV, and surface topology results. Additionally, printed copper was more corrosion-resistant than wrought …

Dpd Guided Insight On The Formation Process Of Polyethersulfone Membranes By Nonsolvent Induced Phase Separation And The Effects Of Additives, Eric Ledieu

Graduate Theses and Dissertations

Dissipative particle dynamics (DPD), a coarse grain simulation method, was applied to the membrane formation process of non-solvent induced phase separation (NIPS) to gain further insight on the mechanism of certain variables and how they affect the final morphology. NIPS involves two solutions, an organic polymer dissolved in an organic solvent colloquially called the dope and an aqueous coagulation bath, brought into contact with one another. The solvents then mix, causing the polymer to fall out of solution as an asymmetric membrane with a dense surface layer and a more open subsurface layer in response to the decreasing solubility. Polyethersulfone …

Corrosion Case Study On Automobile, Grace Ajayi, Xinran Pan, Geethu Sasikala, Marshall S. Yang

Chemistry Publications

No abstract provided.

Targeting Lncrna Ddit4-As1 Sensitizes Triple Negative Breast Cancer To Chemotherapy Via Suppressing Of Autophagy, Ting Jiang, Jiaojiao Zhu, Shilong Jiang, Zonglin Chen, Ping Xu, Rong Gong, Changxin Zhong, Yueying Cheng, Xinyuan Sun, Wenjun Yi, Jinming Yang, Wenhu Zhou, Yan Cheng

Markey Cancer Center Faculty Publications

In this study, it is found that the lncRNA, DNA damage inducible transcript 4 antisense RNA1 (DDIT4-AS1), is highly expressed in triple-negative breast cancer (TNBC) cell lines and tissues due to H3K27 acetylation in the promoter region, and promotes the proliferation, migration, and invasion of TNBC cells via activating autophagy. Mechanistically, it is shown that DDIT4-AS1 induces autophagy by stabilizing DDIT4 mRNA via recruiting the RNA binding protein AUF1 and promoting the interaction between DDIT4 mRNA and AUF1, thereby inhibiting mTOR signaling pathway. Furthermore, silencing of DDIT4-AS1 enhances the sensitivity of TNBC cells to chemotherapeutic agents such as paclitaxel both …

Hydrothermal Liquefaction Of Saccharina Latissima For The Production Of Biofuel, Mayokun A. Oke

Mechanical Engineering Theses

We performed hydrothermal liquefaction of brown macroalga (Saccharina latissima) in the presence of homogenous and heterogenous catalysts such as KOH, Na₂CO₃, Pd/C, HZSM-5, Ce/HZSM-5, and Ni/SiO₂-Al₂O₃ in hot compressed water, to investigate their effects on product yield and composition in the biocrude. To investigate hydrocarbon production, we used methanol as co-solvent (methanol-to-water 1/4 vol.%) and as the only liquefaction solvent. We carried out the experiments in a batch reactor at 330^oC and 120-130 bar, and varying temperature, algae-to-water ratio, residence time, and pretreatment method. The biocrude yields …

Bimetallic Compound Catalysts With Multiple Active Centers For Accelerated Polysulfide Conversion In Li-S Batteries, Wu-Xing Hua, Jing-Yi Xia, Zhong-Hao Hu, Huan Li, Wei Lv, Quan-Hong Yang

Journal of Electrochemistry

Practical applications of lithium-sulfur (Li-S) batteries are hindered mainly by the low sulfur utilization and severe capacity fading derived from the polysulfide shuttling. Catalysis is an effective remedy to those problems by promoting the conversion of polysulfides to reduce their accumulation in the electrolyte, which needs the catalyst to have efficient adsorption ability to soluble polysulfides and high activity for their conversion. In this work, we have proposed a bimetallic compound of NiCo₂S₄ anchored onto sulfur-doped graphene (NCS@SG) to fabricate a catalytic interlayer for Li-S batteries. Compared to CoS, the NiCo₂S₄ demonstrated much higher …

Advances And Challenges On Cathode Catalysts For Lithium-Oxygen Batteries, Bo Wen, Zhuo Zhu, Fu-Jun Li

Journal of Electrochemistry

Aprotic lithium-oxygen batteries (LOBs) with high theoretical energy density have received considerable attention over the past years. However, the oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) at cathodes suffer from slow kinetics for large overvoltages in LOBs. Significant advances on catalysts have been achieved to accelerate cathode kinetics, but understanding on the formation/decomposition processes of Li₂O₂ is limited. Herein, this review highlights the fundamental understanding of the correlation between catalysts and formation/decomposition of Li₂O₂. Various types of cathode catalysts are discussed to reveal the mechanism of formation/decomposition of Li₂O₂, …

Recent Advances In Anode Materials Of Solid Oxide Electrolysis Cells, Geng Zou, Wei-Cheng Feng, Yue-Feng Song, Guo-Xiong Wang

Journal of Electrochemistry

Solid oxide electrolysis cell (SOEC) as an electrochemical energy conversion device has attracted increasing attention due to its large current density, high Faradaic efficiency and energy efficiency. Oxygen evolution reaction at the anode, a four-electron transfer process, is an important half-reaction for SOEC, which contributes to the main polarization resistance and consumes most electric energy during the electrolysis process. Hence, designing anode materials with high activity and stability is crucial for the performance improvement and practical application of SOEC. Recently, some advances have been made in the development of high-performance anode. In the current review, the mechanisms for CO_{2 …}

Preface To Special Issue On Electrocatalysis And Electrosynthesis, Fang-Yi Cheng, Shuang-Yin Wang, Tian-Hua Zhou

Journal of Electrochemistry

No abstract provided.

Anodic Electrocatalysis Of Glycerol Oxidation For Hybrid Alkali/Acid Electrolytic Hydrogen Generation, Xin Feng, Bo-Wen Liu, Ke-Xin Guo, Lin-Feng Fan, Gen-Xiang Wang, Su-Qin Ci, Zhen-Hai Wen

Journal of Electrochemistry

Electrolytic hydrogen production is heavily restricted by high-energy consumption majorly due to the relatively high potential of anodic oxygen evolution reaction (OER). Development of OER-alternative reaction at the anode has been recently proposed as a promising pathway to address the associated issues. In this work, we report a hybrid acid/alkali dual-electrolyte electrolyzer by coupling acidic hydrogen evolution reaction (HER) using commercial Pt/C cathode with alkaline Electrocatalytic glycerol oxidation (GOR) which is implemented by developing a nickel foam (NF) supporting Co₃O₄ nanosheets anode that shows low overpotential and high selectivity toward GOR for formate production. The hybrid acid/alkali …

Highly Dispersed Pt Nanoparticles Root In Single-Atom Fe Sites In Ldhs Toward Efficient Methanol Oxidation, Qing-Cheng Meng, Lin-Bo Jin, Meng-Ze Ma, Xue-Qing Gao, Ai-Bing Chen, Dao-Jin Zhou, Xiao-Ming Sun

Journal of Electrochemistry

Active and durable electrocatalysts for methanol oxidation reaction are of critical importance to the commercial viability of direct methanol fuel cell, which has already attracted growing popularities. However, current methanol oxidation electrocatalysts fall far short of expectations and suffer from excessive use of noble metal, mediocre activity, and rapid decay. Here we report the Pt anchored on NiFe-LDHs surface hybrid for stable methanol oxidation in alkaline media. Based on the high intrinsic methanol oxidation activity of Pt nanoparticles, the substrates NiFe-LDHs further enhanced anti-poisoning ability and maintained unaffected stability after 200,000 s cycle test compared to commercial Pt/C catalyst. The …