Engineering Commons^™

Electrocatalytic Nanomaterials For Reduction Of Hydrogen Peroxide As Potential Radioprotectors, Rui-Hong Jia, Jin-Xuan Zhang, Xiao-Dong Zhang, Mei-Xian Li

Journal of Electrochemistry

Nanomaterials have shown many potential application prospects in the biomedical field, such as medical imaging, drug delivery and biosensing due to their unique physical and chemical properties. In this review we focus on nanomaterials that have shown not only abilities of radiation protection, but also good electrocatalytic activities toward reduction reactions of hydrogen peroxide and oxygen. We discuss the abilities of radiation protection of these nanomaterials that are ascribed to their enzyme-like activities because their catalytic properties provide an effective pathway for scavenging free radicals in vivo via rapid reactions with reactive oxygen species. We also provide insights into electrocatalytic …

Design And Cost Analysis Of Acrylic Acid Plant, Adam Ferrier

Chemical Engineering Undergraduate Honors Theses

The purpose of this project was to model and design a plant to produce 75,000 tons per year of acrylic acid. Using the design in section B.9 of Richard Turton’s Analysis, Synthesis, and Design of Chemical Processes as a starting point, a plant was designed based around the partial oxidation of propylene to acrylic acid. The final plant design produces about 86,000 tons per year of acrylic acid. Using an interest rate of 10%, the plant has a discounted cash flow rate of return of 32% over 2 years of startup and 10 years of operation. Attached is an executive …

Modeling Of Electrochemical Processes At The Magnesium Anode During Struvite Formation, Tobias Dwyer

Chemical Engineering Undergraduate Honors Theses

This study analyzes the current transients observed during the electrochemical formation of struvite from a solution of ammonium phosphate using a pure magnesium and magnesium alloy electrode. Through converting the chronoamperometric data to chronocoulometric data and fitting the data to various models, the driving mechanisms for struvite nucleation were elucidated. While the pure magnesium anode is controlled by only instantaneous nucleation at the electrode, the AZ31 alloy is nucleation controlled at short times and Cottrell diffusion controlled at long times.

Development Of A Ws2 Catalyst For Hydrogen Evolution And Improvement Via Platinum Nanoparticle Decoration, Alexander O'Brien

Chemical Engineering Undergraduate Honors Theses

In response to a growing global need to improve utilization of green energy, the concept of renewable energy storage via electrolytic hydrogen production has gained popularity in recent years. However, the prohibitive expense of the bulk platinum catalysts currently used for the hydrogen evolution reaction prevents such a concept from being widely adoptable. This research focuses on a possible alternative catalyst, nanolayer WS₂, which is capable of promoting the hydrogen evolution reaction while maintaining economic viability. Bulk WS₂ was prepared in semiconducting, nanolayer form through liquid phase exfoliation. Prepared catalyst inks consisting of this material demonstrated successful …

Effect Of Thiols For Nitrogen Reduction To Ammonia, Zakary R. Ford

Chemical Engineering Undergraduate Honors Theses

Ammonia is an important chemical used for fertilizers and also a potential carbon-free hydrogen storage medium. The Haber-Bosch process is the main production process, which requires large energy- and capital-input. Therefore, it is crucial to develop an alternate scalable synthesis that provides a less energy intensive and more economical route for synthetic ammonia production. In this paper, a 1Fe1Ni film was functionalized with C₃OH and C₆OH for the electrochemical synthesis of ammonia. This work will provide some insight into how thiol ligands can increase the selectivity of the catalyst for nitrogen reduction reaction and can be …

Nanowire Based Adsorbents/Catalysts For Co2 Capture And Utilization., Apolo Nambo

Electronic Theses and Dissertations

Even today, the major energy source is fossil fuels, which release CO₂, a greenhouse gas that contributes to global warming. CO₂ capture, storage (CCS) and/or utilization (CCU) technologies are two routes to mitigate this problem. Sorbents are being investigated in either temperature swing or pressure swing absorption approaches for carbon capture from flue gases. Solid sorbent based technology is a promising one but suffers from slow kinetics, low capacity and need for high temperatures. Thus, new sorbent materials that can have good CO₂ sorption capacity, recyclability are sought. Similarly, one of the utilization approaches for CO …

Synthesis, Characterization, And Evaluation Of Metal Complexes With Cancer Selective Anti-Proliferative Effects And Hydrogen Evolution Catalytic Properties., Nicholas Vishnosky

Electronic Theses and Dissertations

Bis-thiosemicarbazones (BTSC) and their metal chelates have properties that are useful in several different scientific fields. These systems have already received attention in major fields of biology and engineering. Hydrogen evolution reaction (HER) catalysts need to be cheap and operate under minimal overpotentials with a long lifetime. The treatment of cancer requires, novel agents that have potent cytotoxic activity against cancer cells while displaying minimal side effects. In this dissertation the modular synthesis of these bis-thiosemicarbazone systems is utilized to regulate the redox chemistry for employment in the desired sector of chemistry. The ligand and metal chelates synthesized were characterized …

Preparation And Electrocatalytic Oxygen Reduction Performance Of Self-Doped Sludge-Derived Carbon, Ya-Li Ye, Wei-Ming Feng, Ge Li, Zhen-Chao Lei, Chun-Hua Feng

Journal of Electrochemistry

The development of low-cost, high-performance cathode catalysts is critical for practical application of fuel cells. Here, the N, P-doped porous graphene-like carbon with outstanding oxygen reduction reaction (ORR) performance was synthesized by pyrolysis of surplus sludge, which functioned as a self-doped, self-activated, and self-templated precursor by acclimation with continuous feedings of phenol. The results show that the amounts of microorganisms were enriched after acclimation, with increasing contents of N, P, Fe, as well as C atoms. The increasing pyrolysis temperature resulted in the formation of an ordered graphitic structure, however, the excessively high temperature induced the drop in the amounts …

Experimental Investigations On The Instantaneous Flow Structure In Circulating Fluidized Beds, Xiaoyang Wei

Electronic Thesis and Dissertation Repository

Knowing the instantaneous flow structure is of great importance for the understanding of gas-particle interaction and for the prediction of reactor performances. In this thesis, a systematic and comprehensive study has been conducted on the instantaneous flow structure in a narrow rectangular riser (19 mm in thickness, 114 mm in width and 7.6 m in height), in a cylindrical riser (76 mm in diameter, 10.2 m in height) and in a cylindrical downer (50 mm in diameter, 4.9 m in height). A wider range of operating conditions has been achieved in risers and downer with superficial gas velocity from 3.0 …

Cnt-Tio2 Composites For Photocatalytic Oxidation Of Atmospheric Pollutants, Alison Chan

Kansas State University Undergraduate Research Conference

The design of catalysts for growth of carbon nanotubes is studied to develop recipes and mechanisms for controlled and scalable growth of carbon nanotubes (CNTs). The objective of the study is to tune the photocatalytic properties of titanium dioxide (TiO₂) by coupling to multiwalled carbon nanotubes (MWNTs). Multiwalled CNTs have been shown to act as an electron sink when coupled with TiO₂, thereby inhibiting electron-hole recombination and enhancing photocatalytic degradation of environmental pollutants. A test using acetaldehyde confirmed our findings in the field, where the loading ratio of 99 wt% TiO₂ (1 wt% CNTs) has a high …

Natural Gas Conversion Into Value Added Chemicals Using Solid Acid Catalysts, Swarom Ravindra Kanitkar

LSU Doctoral Dissertations

Direct, non-oxidative conversion of natural gas to value-added chemicals has been identified as one of the grand challenges of the 21^st century. Circumventing indirect and costly reforming steps is highly sought after and solid acids can play an important role in that.

The direct conversion of methane to higher hydrocarbons and hydrogen can be catalyzed using “superacids” at < 450 °C. Reported superacid catalysts in solid, liquid, and gas phase included sulfated zirconia (SZ), HF-SbF₅, FSO₃H-SbF₅, and HBr-AlBr₃. Liquid and gas phase superacids presented difficulties in separation while the solid ones provided low yields. Here, we report a new class of Br-based solid superacids, AlBr_x/H-ZSM-5 (“ABZ-5”, …

Photocatalytic Degradation Of Profenofos And Triazophos Residues In The Chinese Cabbage, Brassica Chinensis, Using Ce-Doped Tio2, Xiangying Liu, You Zhan, Zhongqin Zhang, Lang Pan, Lifeng Hui, Kailin Liu, Xuguo Zhou, Lianyang Bai

Entomology Faculty Publications

Pesticides have revolutionized the modern day of agriculture and substantially reduced crop losses. Synthetic pesticides pose a potential risk to the ecosystem and to the non-target organisms due to their persistency and bioaccumulation in the environment. In recent years, a light-mediated advanced oxidation processes (AOPs) has been adopted to resolve pesticide residue issues in the field. Among the current available semiconductors, titanium dioxide (TiO₂) is one of the most promising photocatalysts. In this study, we investigated the photocatalytic degradation of profenofos and triazophos residues in Chinese cabbage, Brassica chinensis, using a Cerium-doped nano semiconductor TiO₂ (TiO …

Theoretical Investigation Of The Ring Opening Of Cyclohexane On Ir(111) And Pt(111), Kushal Ghale

LSU Master's Theses

Diesel engines have higher fuel efficiency and can burn cleaner than gasoline engines. To enhance quality of diesel fuels as measured by the cetane number (CN), the removal of aromatic compounds is necessary. A potentially highly efficient approach would be to convert aromatics to saturated cycloparaffin, followed by selective ring opening to linear or branched alkanes, to increase the CN. Here the focus of the project is to study the mechanism of metal-catalyzed ring opening (RO) of cyclohexane (denoted CHA, or c-C₆H₁₂) through theoretical and computational modeling. CHA, a simplest cycloparaffin, is used as probe molecule …

Fischer–Tropsch: Product Selectivity–The Fingerprint Of Synthetic Fuels, Wilson D. Shafer, Muthu Kumaran Gnanamani, Uschi M. Graham, Jia Yang, Cornelius M. Masuku, Gary Jacobs, Burtron H. Davis

Center for Applied Energy Research Faculty and Staff Publications

The bulk of the products that were synthesized from Fischer–Tropsch synthesis (FTS) is a wide range (C₁–C₇₀₊) of hydrocarbons, primarily straight-chained paraffins. Additional hydrocarbon products, which can also be a majority, are linear olefins, specifically: 1-olefin, trans-2-olefin, and cis-2-olefin. Minor hydrocarbon products can include isomerized hydrocarbons, predominantly methyl-branched paraffin, cyclic hydrocarbons mainly derived from high-temperature FTS and internal olefins. Combined, these products provide 80–95% of the total products (excluding CO₂) generated from syngas. A vast number of different oxygenated species, such as aldehydes, ketones, acids, and alcohols, are also embedded in this product range. …

Recent Developments In Surface/Interface Modulation And Structure-Performance Relationship Of Cathode Catalysts For Li-Air Batteries, Rui Gao, Jun-Kai Wang, Zhong-Bo Hu, Xiang-Feng Liu

Journal of Electrochemistry

Lithium-air battery has been considered to be one of the most promising secondary battery systems because of its high energy density. However, the sluggish kinetics of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) on the cathode, and the high overpotential, poor cycle stability and low rate capacity have severely blocked the development and application of Li-air battery. One of the effective strategies to alleviate these issues is to develop cathode catalysts for Li-air batteries. The design and development of bifunctional cathode catalysts with high activity and efficiency on both ORR and OER is highly desired for Li-air …

Ni/Mn3O4/Nimn2O4 Double-Shelled Hollow Spheres Embedded Into Reduced Graphene Oxide As Advanced Anodes For Sodium-Ion Batteries, Chong Yan, Hua-Ri Kou, Bo Yan, Xiao-Jing Liu, De-Jun Li, Xi-Fei Li

Journal of Electrochemistry

Delicately building the unique nanocomposite with the combination of hollow structure and reduced graphene oxide (rGO) is highly desirable and still remains a great challenge in the field of energy conversion and storage. In this work, Ni/Mn₃O₄/NiMn₂O₄ double-shelled hollow spheres coated by rGO (denoted as R-NMN) have been successfully synthetized via one-step rapid solvothermal treatment followed by subsequent annealing for the first time. Served as anodes for sodium ion batteries (SIBs), the R-NMN composite containing 25wt% rGO exhibits a high discharge capacity of 187.8 mAh·g^-1 after 100 cycles at 50 mA·g^{-1 …}

Synthesis Of Flower-Like Vanadium Disulfide For Lithium Storage Application, Pan Li, Jian Liu, Wei-Yi Sun, Hai-Xia Li, Zhan-Liang Tao

Journal of Electrochemistry

In order to improve the electrochemical properties of vanadium disulfide (VS₂) as an electrode material in Li-ion battery, the flower-like VS₂ was prepared by a one-step hydrothermal method with the addition of polyethylene glycol 400. The phase and morphology of the product were characterized by using X-ray diffraction and field emission scanning electron microscopy. During the growth process, it was observed that the flower-like VS₂ was interspersed with several hexagonal vanadium disulfide nanosheets, which had a high specific surface area and excellent structural stability. The flower-like VS₂ was used for the cathode material test in …

Effect Of Pt Promotion On The Ni-Catalyzed Deoxygenation Of Tristearin To Fuel-Like Hydrocarbons, Ryan Loe, Kelsey Huff, Morgan Walli, Tonya Morgan, Dali Qian, Robert Pace, Yang Song, Mark Isaacs, Eduardo Santillan-Jimenez, Mark Crocker

Center for Applied Energy Research Faculty and Staff Publications

Pt represents an effective promoter of supported Ni catalysts in the transformation of tristearin to green diesel via decarbonylation/decarboxylation (deCO_x), conversion increasing from 2% over 20% Ni/Al₂O₃ to 100% over 20% Ni-0.5% Pt/Al₂O₃ at 260 °C. Catalyst characterization reveals that the superior activity of Ni-Pt relative to Ni-only catalysts is not a result of Ni particle size effects or surface area differences, but rather stems from several other phenomena, including the improved reducibility of NiO when Pt is present. Indeed, the addition of a small amount of Pt to the supported Ni …

Continuous Catalytic Deoxygenation Of Waste Free Fatty Acid-Based Feeds To Fuel-Like Hydrocarbons Over A Supported Ni-Cu Catalyst, Ryan Loe, Yasmeen Lavoignat, Miranda Maier, Mohanad Abdallah, Tonya Morgan, Dali Qian, Robert Pace, Eduardo Santillan-Jimenez, Mark Crocker

Center for Applied Energy Research Faculty and Staff Publications

While commercial hydrodeoxygenation (HDO) processes convert fats, oils, and grease (FOG) to fuel-like hydrocarbons, alternative processes based on decarboxylation/decarbonylation (deCO_x) continue to attract interest. In this contribution, the activity of 20% Ni-5% Cu/Al₂O₃ in the deCO_x of waste free fatty acid (FFA)-based feeds—including brown grease (BG) and an FFA feed obtained by steam stripping a biodiesel feedstock—was investigated, along with the structure-activity relationships responsible for Ni promotion by Cu and the structural evolution of catalysts during use and regeneration. In eight-hour experiments, near quantitative conversion of the aforementioned feeds to diesel-like hydrocarbons was achieved. …

Facile Synthesis Of A Tailored-Designed Au/Pt Nanoanode For Enhanced Formic Acid, Methanol, And Ethylene Glycol Electrooxidation, Yaser M. Asal Mr., Islam M. Al-Akraa Dr, Ahmad M. Mohammad Prof

Chemical Engineering

The recent revolution in nanoscience and global energy demand have motivated research in liquid fuel cells (LFCs) due to their enhanced efficiency, moving flexibility, and reduced contamination. In line with this advancement, a glassy carbon (GC) electrode was modified with platinum (PtNPs) and gold (AuNPs) nanoparticles to fabricate a nanosized anode for formic acid, methanol, and ethylene glycol electrooxidation (abbreviated, respectively, to FAO, MO, and EGO), of the key anodic reactions of LFCs. The deposition sequence of the catalyst’s layers was important where the Au/Pt/GC electrode (in which PtNPs were directly deposited onto the GC surface followed by AuNPs—surface coverage …

Compression Set Improvement Of Thermoplastic Vulcanizates For High Temperature Tubing, Mitchell Valaitis

Williams Honors College, Honors Research Projects

It was hypothesized that increasing the curative level of the fluorocarbon rubber (FKM) used in manufacturing of thermoplastic vulcanizate (TPV) materials would decrease the compression set values of the TPV enough for it to be suitable as a flexible, lightweight alternative to high operating temperature thermoset rubber tubing currently being used for power steering hose. First, promising TPV formulations were identified by varying the polyamide (PA) and FKM used in a Brabender mixer. Four different types of polyamide and four different types of FKM were investigated, with two of the FKM types and one polyamide type identified as being promising. …

Improving The Delivered Specific Impulse Of Composite Rocket Propellant Through Alteration Of Chemical Composition: Methodology And Parameters For Characterization Of Propellant And Validation Of Simulation Software Common To The Amateur Rocketry Community, Isaac O'Brien, Austin Ryan

Williams Honors College, Honors Research Projects

In this study, two solid composite rocket propellants were designed utilizing ProPEP, a rocket propellant formulation software common in the amateur and hobby rocketry communities. The two propellants were designed to optimize specific impulse relative to a literature propellant designed by 1020 Research Labs. The literature propellant was also tested in order to validate the design of experiment as well as the mixing and testing procedures. All three propellants, which includes the literature propellant RCS-P, and the two novel propellants AKR-P1 and AKR-P2 were characterized with static tests. The results of the static tests provide data on propellant performance and …

Engineering Of Earth-Abundant Electrochemical Catalysts, Dylan D. Rodene

Theses and Dissertations

Alternative energy research into hydrogen production via water electrolysis addresses environmental and sustainability concerns associated with fossil fuel use. Renewable-powered electrolyzers are foreseen to produce hydrogen if energy and cost requirements are achieved. Electrocatalysts reduce the energy requirements of operating electrolyzers by lowering the reaction kinetics at the electrodes. Platinum group metals (PGMs) tend to be utilized as electrocatalysts but are not readily available and are expensive. Ni_1-xMo_x alloys, as low-cost and earth-abundant transition metal nanoparticles (NPs), are emerging as promising electrocatalyst candidates to replace expensive PGM catalysts in alkaline media. Pure-phase cubic and hexagonal Ni_{1-x …}

Chemically Dealloyed Fe-Based Metallic Glass With Void Channels-Like Architecture For Highly Enhanced Peroxymonosulfate Activation In Catalysis, J.C. Wang, S.X. Liang, Z. Jia, W.C. Zhang, W.M. Wang, Y.J. Lui, J. Lu, L.C Zhang

Research outputs 2014 to 2021

Metallic glasses (MGs) with their intrinsic disordered atomic structure and widely controllable atomic components have recently emerged as fascinating functional materials in wastewater treatment. Compared to crystalline alloys, the less-noble atomic components in monolithic metallic glass are more efficient to be selectively dissolved during dealloying process. This work reported a facile chemical dealloying approach to fabricate a void channels-like structured MG with the elemental components of Fe73.5Si13.5B9Cu1Nb3 for methylene blue (MB) degradation. Results indicated that the dealloyed Fe73.5Si13.5B9Cu1Nb3 MGs with the void channels-like morphology presented a significant improvement of catalytic efficiency and reusability. The dye degradation reaction rate (kobs) of …

Facile Synthesis Of A Tailored-Designed Au/Pt Nanoanode For Enhanced Formic Acid, Methanol, And Ethylene Glycol Electrooxidation, Islam M. Al-Akraa Dr., Yaser M. Asal Mr

Chemical Engineering

The recent revolution in nanoscience and global energy demand have motivated research in liquid fuel cells (LFCs) due to their enhanced efficiency, moving flexibility, and reduced contamination. In line with this advancement, a glassy carbon (GC) electrode was modified with platinum (PtNPs) and gold (AuNPs) nanoparticles to fabricate a nanosized anode for formic acid, methanol, and ethylene glycol electrooxidation (abbreviated, respectively, to FAO, MO, and EGO), of the key anodic reactions of LFCs. The deposition sequence of the catalyst’s layers was important where the Au/Pt/GC electrode (in which PtNPs were directly deposited onto the GC surface followed by AuNPs—surface coverage …

Enhanced Electro-Oxidation Of Methanol At Pt-Au Nanocatalyst For Direct Methanol Fuel Cells, Islam M. Al-Akraa Dr., Yaser M. Asal Mr, Ahmad M. Mohammad Prof

Chemical Engineering

In this investigation, a Pt-Au nanocatalyst prepared by the coelectrodeposition of Pt (PtNPs) and Au (AuNPs) nanoparticles is assembled onto a glassy carbon (GC) electrode for efficient methanol oxidation (MO). Several molar ratios between PtNPs and AuNPs have been used and the corresponding catalytic activity towards MO is tracked. The Pt1:Au1 catalyst showed the highest catalytic activity (5 times higher oxidation peak current (Ip) and a 126 mV negative shift in the onset potential (Eonset) toward MO). The catalyst’s morphology, composition and activity are investigated and the ehancement mechanism is recognized.

A Simple And Effective Way To Overcome Carbon Monoxide Poisoning Of Platinum Surfaces In Direct Formic Acid Fuel Cells, Islam M. Al-Akraa Dr., Yaser M. Asal Mr, Sohair A. Darwish Ms

Chemical Engineering

A glassy carbon (GC) electrode modified with multi-walled carbon nanotubes (MWCNTs) and platinum nanoparticles (PtNPs), Pt/MWCNTs-GC, has been introduced for formic acid electro-oxidation (FAO). A similar loading of PtNPs has been conserved for a proper comparison between the Pt/MWCNTs-GC and the unmodified Pt/GC electrodes. The modification with MWCNTs could enhance the loading of PtNPs onto the GC electrode in a way that minimizes its agglomeration and increases its dispersion in the CNTs network. This not only increases the surface area exposed to the reaction but also interrupts the contiguity of the Pt active sites minimizing the adsorption of the poisoning …

Approximate Analytical Solution For Mathematical Models Of Thermal Ignition And Non-Isothermal Catalytic Zero Order Reaction In A Spherical Geometry, Moustafa A. Soliman

Chemical Engineering

In this paper an approximate analytical solution for the Frank-Kamenetskii equation modeling thermal ignition without the depletion of the combustibles in a spherical annulus and non-isothermal zero order reaction in spherical catalyst particle is presented. The approximate solution is compared with the numerical solution and is in good agreement with the numerical solution. The approximate solution obtained is valid for all values of the distance parameter. Multiple solutions occur for some range of Frank-Kamenetskii parameter (λ). The multiplicity is infinite for the case of a solid sphere and λ=2.Interesting relation is obtained for λ at the turning points. For the …

A Promising Modification Of Pt Surfaces With Cnts For Decreasing Poisoning Impact In Direct Methanol Fuel Cells, Islam M. Al-Akraa Dr., Yaser M. Asal Mr, Aya A. Khalifa Ms.

Chemical Engineering

Direct methanol fuel cells (DMFCs) are clean energy sources that have many applications due to the high energy density of methanol as a fuel. However, this type of fuel cells (FCs) has limitations that are preventing it from being commercialized. One such limitation is the adsorption of intermediates such as CO into the surface of the Platinum (Pt) catalyst during methanol oxidation (MO) which deactivates its active sites, where the reaction is taking place, and leads to poisoning of the electrode over the long term. In this study, multi-walled carbon nanotubes (MWCNTs) have been introduced to the Pt-modified glassy carbon …

Towards Sustainable Production Of Chemicals And Fuels From The Fast Pyrolysis Of Waste Polyolefin Plastics, Ulises Gracida Alvarez

Dissertations, Master's Theses and Master's Reports

The increasing amount of plastic waste (PW) generation has become an important concern due to the leveled-off recycling rates. Therefore, governmental agencies around the world, including state governments in the United States, have proposed initiatives to minimize the amount of PW that is landfilled and encourage recycling or energy recovery. Circular economy is a strategy that attempts on reusing PW to produce new polymers while avoiding its disposal and the use of virgin material. Chemical recycling raises an interesting technology prospect due to the potential reduction of pollutant emissions and the establishment of a circular economy through the production of …