Chemical Engineering Commons^™

The Composition Of Gases From A Diffusion Flame Above Longleaf Pine Needle Fuel Beds, David R. Weise, Thomas H. Fletcher, Timothy J. Johnson, Weimin Hao, Russell G. Tonkyn, Catherine A. Banach, Javier Palarea-Albaladejo, Mahsa Alizadeh, Stephen Baker

Faculty Publications

The gas and tar composition of a wildland fire diffusion flame from longleaf pine needles is currently relatively unmeasured and more data are needed to fill in the gap between pyrolysis data and smoke plume data, thus improving physical and chemical modeling of wildland smoke formation. A pilot experiment to measure light gas and tar composition of such a flame is described for three flame zones: persistent flame (flame base), intermittent flame, and smoke plume. Flame gases from 24 experimental fires were collected in canisters and analyzed for CO2, CO, H2, CH4, and C2 to C7 hydrocarbon gases. Other light …

Feasibility Of Upcycling Spent Lithium-Ion Battery To Carbon Dioxide Capture Adsorbent, Chimezie Frank Onwudinjo

Master’s Theses

This study investigates the feasibility of repurposing spent lithium-ion battery (SLIB) to lithium orthosilicate (Li₄SiO₄), a high temperature carbon dioxide sorbent. Two synthesis pathways including conventional acid-leaching method (Scenario 1) and a pyrolysis-based route (Scenario 2) were explored. Additionally, techno-economic analysis (TEA) and lifecycle assessment (LCA) of the two processes were also performed. Different analytical characterization techniques were performed to understand the material properties of Li₄SiO₄ including surface area, crystallinity, morphology and thermal stability. CO₂ capture performance of the synthesized Li₄SiO₄ was tested in a thermogravimetric analyzer (TGA) using …

Mechanical Fractionation Of Wheat Middlings For Application In Pyrolysis And Animal Feed, Okwudili I. Obiakor

Dissertations, Master's Theses and Master's Reports

Wheat middlings are grain byproducts that are underused for bioenergy production despite having a high lignocellulose content. Its use as a feedstock for catalytic pyrolysis depends on effective and sustainable fractionation to enhance efficiency and product yield. This study tested mechanical pre-fractionation (sieving and air classification) to reduce ash content of certain fractions to < 1% for catalytic pyrolysis and enrich nutrient levels of other fractions for feed applications. Wheat middlings were separated into 11 fractions using screen sizes from 106 µm to 1651 µm, and the composition of each fraction was characterized (ash, protein, structural carbohydrates, lignin, starch, and simple sugars). For cyclone separation, a full factorial design was used to study the effect of air velocity (15,18, 20 m/s) and feed rate (33, 35, 38 kg/h) on the amount of material collected in the underflow and overflow, and the composition of these fractions was characterized. Sieving showed a pronounced segregation of ash content, from 4.5% to 6.5% in wheat middlings fractions, with 5.7% being the lowest for coarse fractions which has higher lignocellulose content, and 4.5% in the fine fraction (150-212 µm). The same defined enrichment was observed in all nutrients except for protein. Starch enrichment zone were defined in the fine fractions (212 µm and below), for structural carbohydrates and lignin in the coarse fractions (600 µm and above), and for ash in coarse fractions (1180-1651 µm). In contrast, protein content was not significantly different between various fractions (p value=0.787). The fiber rich fraction (> 600 µm), suitable for pyrolysis, which have a composite ash value of 6.0% can be sorted and mixed with intermediate fractions to reduce ash to 5.3% and the remaining fractions rich in digestible nutrients used for animal feed formulation. Compared to sieving, cyclone separations did not …

Bioprospecting Of Wheat Straw Pyrolysis Aqueous Phase To Combat Multi-Drug Resistant Pathogens, Srividhya K

Theses and Dissertations

Hospital-acquired infections (HAIs) significantly contribute to the emergence and spread of antimicrobial resistance (AMR), primarily through the contamination of high-touch surfaces. Current disinfectants have drawbacks like high environmental persistence, ecotoxicity, and resistance development, prompting the need for environmentally friendly alternatives.

One potential approach is pyrolysis, during which the biomass components are broken down into solid, liquid, and pyro-gas. The aqueous phase of the liquid fraction is usually discarded as waste, but it contains a variety of organic compounds that have the potential for antibacterial and antifungal activity. The present study assessed the anti-infective and anti-biofilm properties of wheat straw pyrolysis …

H2-Rich Biogas Production From Fixed Bed Wheat Straw Pyrolysis And The Potential Of Produced Biochar As H2 Storage Material, Tawanda Matamba, Hussein Rasool Abid, Alireza Keshavarz, Stefan Iglauer

Research outputs 2022 to 2026

H2 is a clean energy source, and is targeted as one of the ways to transition from fossil fuels. However, there are drawbacks in production and storage of hydrogen. To cover the supply, we need H2 from many resources and because of its low density we need materials that can store bulky quantities of H2. Here we investigated the potential of a renewable source (waste wheat straw) to produce and store H2 through pyrolysis and adsorption. The impact of pressure and temperature (500–900 °C, and 1.01–30 bar range) on the selectivity of H2 rich gas production was systematically investigated; and …

Effect Of Household Oil Contamination And Agricultural Soil Contamination On Phyllosilicate Nanocatalyst Performance During Pyrolysis Of Polyolefins, Joey Velasquez

Master's Theses

The effect of household oil and agricultural soil contamination on catalyst performance during polyolefin pyrolysis was simulated on mixed virgin plastic pellets by evaluating contamination influence on mixed plastic degradation temperatures. Three phyllosilicate nanocatalysts including Fulcat435, Fulcat22F and Y-Zeolite were evaluated in this work based on a literature review of catalyzed plastic pyrolysis and these catalysts’ ability to lower plastic decomposition temperature by 50 °C – 100 °C. These findings were confirmed in this research through thermogravimetric analysis of a polyolefin mixture and further developed in furnace experiments containing household oil and agricultural contamination. Household oil contamination deactivated each of …

Valorization Of The Polymeric Constituents In Plastic Wastes Through Thermo-Chemical Processes By Using Viable Metal Oxides Additives, Labeeb Ali

Thesis/ Dissertation Defenses

The rapid accumulation of different types of plastic waste necessitates the development of effective and economically viable waste management operations. Such a process should ideally not only mitigate associated environmental burdens but also recycle and recover value-added products. Through incineration or pyrolysis, thermal processing has emerged as a mainstream approach to waste management of the ever-increasing loads of different categorized plastic wastes. Throughout the work of the thesis, we have utilized a multitude of complementary techniques spanning material characterizations, catalysis, kinetic modelling, and density functional theory (DFT) to comprehend the complex chemistry that underpins catalytic chemical recycling of plastic wastes. …

Valorization Of The Polymeric Constituents In Plastic Wastes Through Thermo-Chemical Processes By Using Viable Metal Oxides Additives, Labeeb Hamad Ali

Dissertations

The rapid accumulation of different types of plastic waste necessitates the development of effective and economically viable waste management operations. Such a process should ideally not only mitigate associated environmental burdens but also recycle and recover value-added products. Through incineration or pyrolysis, thermal processing has emerged as a mainstream approach to waste management of the ever-increasing loads of different categorized plastic wastes. Throughout the work of the thesis, we have utilized a multitude of complementary techniques spanning material characterizations, catalysis, kinetic modelling, and density functional theory (DFT) to comprehend the complex chemistry that underpins catalytic chemical recycling of plastic wastes. …

Chromatographic Analysis Of The Chemical Composition Of Pyrolysis Distillate, Sh.T. Juraev, B.F. Muxiddinov, U.T. Tailakov

Chemical Technology, Control and Management

The paper presents the results of a study of the physico-chemical characteristics of the liquid fraction of products of thermal oxidative pyrolysis of worn tires. The mass fraction of the volatile gas compounds, the optimal boiling points of the obtained condensates and the flashpoint of pyrolysis liquids, together with the mass composition of cracking products of rubber products at high-temperature pyrolysis at a temperature of 800-900 °C, were determined. Chromatographic analysis allowed us to determine the composition, mainly the mass composition of pyrolysis products, which consisted of carbon (42.8%), higher aliphatic and aromatic hydrocarbons (17.0%), methane (10.2%), benzene (4.2%) and …

Selective Production Of Levoglucosan (Lg) From Pyrolysis Of Date Pits And Its Catalytic Transformation Into Transportation Fuels, Ala Hamid Higazi

Theses

Levoglucosan (LG) or (1,6-anhydro-β-D-glucopyranose) signifies important sugar derivatives produces in appreciable quantities from thermochemical and biochemical degradation of biomass. It is often regarded as an important platform chemical for the synthesis of value-added products, most notably styrene and furans. The work in this thesis entails two broad aims; to produce LG from pyrolysis of date pits; and then convert the LG into transportation fuels through a hydrodeoxygenation (HDO) reaction. The particular choice of date pits stems from its local relative abundance as a waste biomass. Aiming to further improve the yield of levoglucosan yields from pyrolysis of date pits, pre-treatment …

Upgrading Biomass To Bio-Oil: Catalytic Hydrodeoxygenation And Pyrolysis Of Vanillin And Anisole Biomass Model Compounds, Ahmad J. Yaghi

Thesis/ Dissertation Defenses

The purpose of this project is to investigate capacity of selected formulations of catalysts toward the hydrodeoxygenation (HDO) of biomass model compounds in the gas phase with the underlying aim to produce hydrocarbon cuts that can be directly used as transportation fuels. The first part of this project is to devoted to illustrate procedures for the synthesis of potent (HDO) catalysts. Synthesized catalysts encompass nickel (Ni), cobalt (Co) and palladium (Pd) supported on zeolite, cerium oxide (CeO₂) or alumina (Al2O₃). Various characterization techniques such as X-ray Diffraction (XRD), Temperature Programmed Reduction (TPR) were deployed to comprehend …

Upgrading Biomass To Bio-Oil: Catalytic Hydrodeoxygenation And Pyrolysis Of Vanillin And Anisole Biomass Model Compounds, Ahmad J. Yaghi

Theses

The purpose of this project is to investigate capacity of selected formulations of catalysts toward the hydrodeoxygenation (HDO) of biomass model compounds in the gas phase with the underlying aim to produce hydrocarbon cuts that can be directly used as transportation fuels. The first part of this project is to devoted to illustrate procedures for the synthesis of potent (HDO) catalysts. Synthesized catalysts encompass nickel (Ni), cobalt (Co) and palladium (Pd) supported on zeolite, cerium oxide (CeO₂) or alumina (Al₂O₃). Various characterization techniques such as X-ray Diffraction (XRD), Temperature Programmed Reduction (TPR) were deployed …

Deconstructed Plastic Substrate Preferences Of Microbial Populations From The Natural Environment, Lindsay I. Putman, Laura G. Schaerer, Ruochen Wu, Daniel G. Kulas, Ali Zolghadr, Rebecca Ong, David Shonnard, Stephen Techtmann

Michigan Tech Publications, Part 1

Over half of the world's plastic waste is landfilled, where it is estimated to take hundreds of years to degrade. Given the continued use and disposal of plastic products, it is vital that we develop fast and effective ways to utilize plastic waste. Here, we explore the potential of tandem chemical and biological processing to process various plastics quickly and effectively. Four samples of compost or sediment were used to set up enrichment cultures grown on mixtures of compounds, including disodium terephthalate and terephthalic acid (monomers of polyethylene terephthalate), compounds derived from the chemical deconstruction of polycarbonate, and pyrolysis oil …

Bio-Oil Production From Hydrothermal Liquefaction Of Pennisetum Purpureum X Pennisetum Typhoideum, Tossapon Katongtung, Sanphawat Phtomphithak, Thossaporn Onsree, Nakorn Tippayawong, Jochen A. Lauterbach

Faculty Publications

Among renewable and sustainable energy resources, biomass plays a vital role. Agricultural residues/wastes, energy crops, and lignocellulosic biomass could potentially be major feedstocks for biorefineries. In Thailand, one of the most interesting energy crops is hybrid giant Juncao grass (GJG) or Pennisetum purpureum × Pennisetum typhoideum. GJG can be easily grown and has relatively high yields under tropical climates. Herein, conversion of GJG to biofuels via hydrothermal liquefaction (HTL) was investigated using batch reactors under varying reaction temperatures of 250–350 ◦C and biomass-to-deionized water concentrations of 15–25 wt% at a fixed residence time of 30 min. Changes in temperature and …

Biochar Preparation, Investigation Of Properties And Application As A Low-Cost Adsorbent – A Review, A Kh Aripov, S M. Turabdzhanov, Sh Komilova, O Sh Qodirov, G S. Rakhimova, T V. Darabkova, Zh Aimenova, L S. Rakhimova

Technical science and innovation

An overview of current developments in biochar application in water and wastewater treatment is given in this article, along with a brief explanation of the sorption mechanisms for removing contaminants and the techniques for biochar preparation. In order to encourage the continued use of biochar in effective water and wastewater treatment, future research directions and environmental concerns about biochar are also presented.

Date-Leaf Carbon Particles For Green Enhanced Oil Recovery, Bashirul Haq, Md Abdul Aziz, Dhafer Al Shehri, Nasiru Salahu Muhammed, Shaik Inayath Basha, Abbas Saeed Hakeem, Mohammed Ameen Ahmed Qasem, Mohammed Lardhi, Stefan Iglauer

Research outputs 2022 to 2026

Green enhanced oil recovery (GEOR) is an environmentally friendly enhanced oil recovery (EOR) process involving the injection of green fluids to improve macroscopic and microscopic sweep efficiencies while boosting tertiary oil production. Carbon nanomaterials such as graphene, carbon nanotube (CNT), and carbon dots have gained interest for their superior ability to increase oil recovery. These particles have been successfully tested in EOR, although they are expensive and do not extend to GEOR. In addition, the application of carbon particles in the GEOR method is not well understood yet, requiring thorough documentation. The goals of this work are to develop carbon …

Investigation Of Recyclable And Renewable Crude Oil From Biomass And Plastics, Golam Chowdhury

Dissertations and Theses

In the present world, the nonrenewable source of petroleum crude oil is suspected to cause irreversible climate impacts. So, refinery companies are looking for renewable and recyclable crude oil (RCOs). Biomass and Plastics are a great sources of RCOs. The goal of this work is to design, build and operate a pyrolysis reactor which is capable of converting different solid feedstock derived from waste to pyrolysis oil. The oils are characterized by GC-MS and sent to BASF Corporation in Iselin, NJ for catalytic upgrading potential. In this study, the feedstock ranged from virgin plastic resins (LDPE, HDPE, PS, PP), recycled …

Application Of Compositional Data Analysis To Determine The Effects Of Heating Mode, Moisture Status And Plant Species On Pyrolysates, David R. Weise, Thomas H. Fletcher, Mohammad-Saeed Safdari, Elham Amini, Javier Palarea-Albaladejo

Faculty Publications

Pyrolysate gas mixtures are multivariate and relative in nature. Statistical techniques applied to these data generally ignore their relative nature. Published data for permanent gases (CO, CO2, H2, CH4) and tars produced by pyrolysing 15 wildland fuels were reanalysed using compositional data analysis techniques. Mass and mole fractions were compositionally equivalent. Plant species, moisture status and heating mode effects on compositional balances formed from subsets of pyrolysates were tested. Plant species affected the amount of phenol, primary and secondary/tertiary tars relative to permanent gases and relative amounts of single- and multi-ring compounds. Plant moisture status affected the amount of CO …

Pyrolysis Kinetics Of Wildland Vegetation Using Model-Fitting Methods, Ellie Amini, Mohammad-Saeed Safdari, Nathan Johnson Brigham, David R. Weise, Thomas H. Fletcher

Faculty Publications

Slow-heating pyrolysis experiments of 14 plant species native to forests in the southern United States were conducted in a TGA to find the kinetic parameters for slow pyrolysis of all live and air-dried plant samples. Kinetic coefficients were determined from the data using model-fitting methods, resulting in single kinetic parameters for the entire pyrolysis process which can be used by wildland fire modelers. The model forms explored here are a simple one-step model and single and multiple reaction distributed activation energy (DAE) models. The mass loss and derivative mass loss data were fitted simultaneously at heating rates of 10, 20, …

Economic Feasibility Of Mixed Plastic Waste Pyrolysis Using Twin Reactor System In Northwest Arkansas, Carol Rogers, Patricia Means, Renato Gonzalez, Kaida Sheets, Hayden Townsend

Chemical Engineering Undergraduate Honors Theses

Plastic waste generation is increasing at an unsustainable rate while recycling solutions remain stagnant. As a chemical means of recycling, mixed plastic waste pyrolysis can generate synthetic oil appropriate for use as fuel in power generation from plastic waste that otherwise accumulates in landfills. With the scaling of a commercial plastic pyrolysis process in Northwest Arkansas (NWA) modeled after an operational sawdust pyrolysis unit in Huntsville, Arkansas, economic analysis resulted in 26.3% internal rate of return. Therefore, construction of a commercial mixed plastic-to-fuel pyrolysis plant is economically justified and should be pursued. To effectively implement the proposed design, NWA must …

Assessment Of A Decentralized Solution For Waste Plastic Management In Developing Regions, Chandniben Ashishkumar Joshi

Theses and Dissertations--Chemical and Materials Engineering

Rapid population growth, urbanization and availability of pre-packaged consumer goods have led to increased generation and consumption of plastic – so much so that it has become ubiquitous in the environment. An affordable, durable, and lightweight material of construction, plastic is used in innumerable products in every country on earth. However, this explosion of consumption coupled with the material’s significantly low degradability have led to serious plastic accumulation challenges, which are now an imminent threat to terrestrial and marine species globally. These challenges are especially acute in developing countries, where capital and infrastructure constraints, poor governmental regulation and lack of …

Clearance Of Solid Household Waste With The Reception Of Alternative Types Of Energy Carriers, Rakhmatullayev F, Turabdhanov S

Technical science and innovation

The research is devoted to improving the technology of obtaining alternative types of energy carriers by applying methods of pyrolysis of unclaimed types of solid domestic wastes of biological origin, which also allow solving the tasks of improving the ecological situation in the places of formation. The practical value and relevance of this research lies in the development of advanced technology for obtaining alternative fuels. The proposed pyrolysis unit allows producing gaseous and liquid hydrocarbons in a continuous cycle. In the atmosphere of the gasifying agent (air, oxygen, water vapor, carbon dioxide or their mixture), the gasification process is primarily …

Structural And Electrochemical Characterizations Of Activated Carbon Derived From Corn Crops For High Performance Energy Storage Devices, Seongwoo Hong

Electronic Theses & Dissertations

The recent attention given to supercapacitors has been driven forward by the need for sustainable and renewable energy resources in the global energy storage market due to soaring energy demand and decreasing availability of fossil fuels. Accordingly, biomass materials as electrode materials for supercapacitors have been innovated due to the characteristic of being naturally abundant, low-cost, and eco-friendly. Therefore, the various parts of corn plants such as corn leaf (CL), grain distiller (CGD), cob (CC), husk (CH), and stem (CS) as biomass electrode materials were prepared and then chemically activated using different masses of potassium hydroxide (KOH) as a chemical …

Comparison Of Pyrolysis Of Live Wildland Fuels Heated By Radiation Vs. Convection, Mohammad-Saeed Safdari, Elham Amini, David R. Weise, Thomas H. Fletcher

Faculty Publications

During wildland fires, which include both planned (prescribed fire) and unplanned (wildfire) fires, live and dead plants may be subject to both radiative and convective heat transfer mechanisms. In this study, the pyrolysis of 14 live plant species native to the forests of the southern United States was investigated using a flat-flame burner (FFB) apparatus under three heating modes in order to mimic pyrolysis of plants during wildland fires. The heating modes were: (1) radiation-only, where the plants were pyrolyzed under a moderate heating rate of 4 °C s−1 (radiative flux of 50 kW m−2); (2) convection-only, where the FFB …

A Review Of 30 Years Of Research Using The Cpd Model, Thomas H. Fletcher

Faculty Publications

The chemical percolation devolatilization (CPD) model for coal pyrolysis was first published in 1989, and a completed version that included the vapor–liquid equilibrium model and cross-linking model was published in 1992. The CPD model was one of three pyrolysis models developed using a lattice model to account for the chemical structure of the coal and was directly based on solid-state ¹³C nuclear magnetic resonance (NMR) measurements of the coal structure. A correlation of coal structure parameters measured by NMR spectroscopy was performed to permit use of the CPD model to determine pyrolysis rates and yields of tars and light …

Preparations And Electrocatalytic Properties Of Cu-Bipy-Btc-Derived Carbon-Based Catalyst For Oxygen Reduction Reaction, Li-Hua Zhang, Jun-Feng Chen, Wan-Tang Huang, Yong-You Hu, Jian-Hua Cheng, Yuan-Cai Chen

Journal of Electrochemistry

Efficient and low-cost oxygen reduction reaction (ORR) electrocatalyst plays a key role for fuel cells. In this paper, ORR active metal organic framework (MOF: Cu-bipy-BTC, bipy = 2,2?-bipyridine, BTC = 1,3,5-tricarboxylate) was prepared using hydrothermal method, and then carbon-based material MOF-800 was obtained from pyrolyzing Cu-bipy-BTC at 800 °C. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), nitrogen sorption isotherm and X-ray photolectron spectroscopy (XPS) were used to characterize the morphologies and structures of the catalysts. Linear sweep voltammetry (LSV) and current-time curve (i-t) were adopted to evaluate the electrocatalytic properties of the catalysts. The results …

Chemical And Physical Modification Of Thiol-Ene And Epoxy-Amine Networks For Advanced Control Of Gas Transport And Flame Retardant Behavior, Vivek Vasagar

Dissertations

Crosslinked polymers are widely used due to its several advantages not limited to high mechanical strength combined with the easy processability. Despite of its popular usage, the fundamental understanding of polymer structure affecting the desired properties is still lacking. This PhD thesis is in two parts, the first part is devoted to the design and developing a basic understanding of structure and chemical composition dependencies of gas transport, whereas in the second part a fundamental relationship between structure to the fire-retardant properties is established.

Membrane based gas separation technique has attracted interest of selective removal of carbon dioxide gas from …

Correlations Of The Elemental Compositions Of Primary Coal Tar And Char, Andrew P. Richards, Colson Johnson, Thomas H. Fletcher

Faculty Publications

Simulations of large-scale coal combustors rely on accurate submodels to describe the chemical and physical changes in coal during reaction. Typically, simplified empirical submodels are tuned to experimental data to reduce the computational complexity. When data are not readily available, simplifying assumptions are used, which can create inaccuracies and biases in a large simulation. One such simplifying assumption in coal research is how to describe the elemental composition of primary pyrolysis products. This paper explores several different empirical model forms to predict the dry, ash-free fractions of C, H, O, N, and S in both the char and tar, using …

Pyrolysis Kinetics Of Live And Dead Wildland Vegetation From The Southern United States, Elham Amini, Mohammad-Saeed Safdari, David R. Weise, Thomas H. Fletcher

Faculty Publications

The fundamental combustion behavior of live wildland vegetation is not fully understood. Since the combustion process during wildland fire starts with pyrolysis, there is a need for better understanding of pyrolysis to develop improved wildland fire models. The kinetics of pyrolysis of live and dead wildland vegetation has not been explored in detail. In this study, the pyrolysis kinetics were determined for 14 different plant species (live and dead) which are all native to the forests in the southern United States. Pyrolysis experiments were carried out in a Thermogravimetric analyzer (TGA) under inert conditions at 5 different heating rates ranged …

Pyrolysis Of Plastic Waste From Medical Services Facilities Into Potential Fuel And/Or Fuel Additives, Bright Kweku Ansah Baiden

Masters Theses

Limited space and high costs for landfilling as well as increasing regulations in plastic waste disposal, has led to high operating costs for organizations involved in managing plastic waste from medical facilities which led to the need to investigate an alternative option such as pyrolysis. The overall goal of this study was to evaluate pyrolysis as a means to repurpose plastic waste obtained from medical service facilities into fuel and fuel additive compounds, with two objectives involving, (1) to examine the effect of heat input (as voltage) and reaction/residence time; and (2) to evaluate the effect of the plastic waste …