Engineering Commons^™

Investigations Of Thermal Treatment Of Softwood Kraft Lignin Under Fractional And Ablative Pyrolytic Conditions, Dideolu J. Daniel

LSU Master's Theses

Lignin is second to cellulose in abundance among polymers in nature. Research studies on the development of new products and material combinations in which lignin degradation/conversion products are involved are still in their infancy, because fundamental knowledge about its structure, reactivity, and material and polymer behavior, is still lacking.

The objective of this research study was to investigate the complex thermal deconstruction and mechanistic behavior of a type of technical lignin, known as Kraft lignin, under depolymerization and to develop operating conditions for parameters influencing resulting product yields and operation of pyrolysis reactors.

Softwood Kraft lignin (s-KL) and methanol-fractionated (ex-KL) …

The Formation Of Polycyclic Aromatic Hydrocarbons From The Pyrolysis Of Model 1-Alkene Fuels, Eva Christine Caspary

LSU Doctoral Dissertations

To understand the role of 1-alkenes and allylic radicals in the reaction pathways leading to the formation and growth of polycyclic aromatic hydrocarbons (PAH), pyrolysis experiments have been performed with three 1-alkene fuels—propylene (CH₂=CH–CH₃), 1-butene (CH₂=CH–CH₂–CH₃), and 1-pentene (CH₂=CH–CH₂–CH₂–CH₃)—at temperatures of 600 – 1000 °C and a fixed residence time of 0.31 s. The experiments are carried out in an isothermal laminar-flow quartz-tube reactor. Analyses of the pyrolysis products by gas-chromatographic and high-pressure liquid-chromatographic techniques reveal that the three fuels differ in: 1) their conversion behavior, 2) the relative amounts of the major C₂ – C₄ species produced, and 3) …

Growth Of Polycyclic Aromatic Hydrocarbons During The Supercritical Pyrolysis Of N-Decane, Subramanian Venkateswaran Kalpathy

LSU Doctoral Dissertations

In order to serve a dual role as a propellant and as a coolant, fuels in the pre-combustion environment of future high-speed aircraft will be exposed to temperatures and pressures of up to 700 °C and 130 atm—conditions that are supercritical for jet fuels. Under such conditions, fuel can undergo pyrolytic reactions leading to the formation of polycyclic aromatic hydrocarbons (PAH), which are precursors to fuel-line solid deposits that can hinder safe operation of the aircraft. Therefore, to prevent solid deposit formation, it is extremely important to understand the PAH formation pathways in the supercritical fuel pyrolysis environment. To better …

Biomass Catalytic Upconversion With A Metallic Catalyst Bed Under Radio Frequency Induction Heating, Mohammad Abu-Laban

LSU Master's Theses

This study investigated the thermal performances of platinum particles when coupled on a steel support, under the application of a radio frequency (RF) field. Platinum nanoparticles were reduced on the surfaces of type-316 stainless steel balls, based on published methods of Pt reduction from chloroplatinic acid. Alternatively, 1wt. % Pt/Al2O3 commercial catalyst pellets were mixed with stainless steel balls and investigated for hydro-deoxygenation of pyrolysis oil from pine sawdust biomass. The catalysts were placed inside an electric insulator tube suspended within a looping copper coil connected to the induction heater, and heated at different power levels. An infrared camera was …

Thermo-Catalytic Upgrading Of Pyrolysis Vapors Using Electromagnetic Heating, Pranjali Devidas Muley

LSU Doctoral Dissertations

Electromagnetic heating offers several advantages such as rapid heating rates, accurate temperature control and energy efficiency over conventional reactors. The goal of this study was to design an effective and energy efficient catalytic reactor for pyrolysis vapor upgrading. An induction based catalytic reactor was designed for upgrading of pyrolysis vapors. The effect of catalyst bed temperatures (290°, 330° and 370°C) and biomass to catalyst ratios of 1, 1.5 and 2 was studied. The results were compared to conventional heating reactor. Induction heating reactor performance exceeded that of conventional heater. The biomass to catalyst ratio of 2 in combination with the …

A Study Of Induction Pyrolysis Of Lignicellulosic Biomass For The Production Of Bio-Oil, Charles Edward Henkel

LSU Master's Theses

The increasing demand for energy coupled with a growing concern that the combustion of fossil fuels has on the environment, through the production of greenhouse gases, has created a demand for renewable energy sources. The demand for renewable energy, particularly liquid transportation fuels, can be met in part by the use of biomass based liquid fuels. There are several methods that can be used to produce biomass based fuels, but only thermochemical conversion (pyrolysis) can readily convert lignocellulosic biomass into a fuel-like liquid, bio-oil. The pyrolytic conditions for obtaining maximum liquid yields vary, but many of the criteria can be …

An Experimental Investigation Of The Effects Of N-Decane On The Supercritical Pyrolysis Of Toluene, Catherine A. Grubb

LSU Master's Theses

Future and current high-speed jet aircraft will require their fuels to act as the primary coolants as well as propellants. Fuels will be exposed to severe temperatures and pressures in hypersonic aircraft, up to 700°C and 130 atm, respectively, conditions that are supercritical for most pure hydrocarbons. Under supercritical conditions, hydrocarbon fuels undergo pyrolytic reactions, which may lead to the formation of polycyclic aromatic hydrocarbons (PAH), known precursors to carbonaceous solid deposits. Such deposits may clog fuel lines and injection nozzles, hindering safe engine performance. Hence, it is important to understand the reactions that lead to the formation of PAH. …

An Experimental Investigation Of The Role Of Small Hydrocarbons And Combustion-Generated Nanoparticles On The Formation And Growth Reactions Of Polycyclic Aromatic Hydrocarbons During The Pyrolysis Of A Model-Fuel And Hydrocarbon Gases, Nimesh Bharat Poddar

LSU Doctoral Dissertations

Polycyclic aromatic hydrocarbons (PAH) are an important class of environmental pollutants formed during fuel combustion or pyrolysis. Therefore, an experimental study has been undertaken to better understand the formation and growth pathways of PAH.

To investigate the efficacy of C₃ species as PAH growth agents in the context of solid fuels, pyrolysis experiments have been performed in an isothermal quartz flow reactor in the temperature range of 700–1000 °C and a fixed residence time of 0.3 s. Experiments are performed with the C₃ hydrocarbon, propyne; with catechol (ortho-dihydroxybenzene), a model-fuel representative of aromatic moieties in coal …

The Effects Of Inorganic Solids And Certain Gases On The Thermal Decomposition Of Catechol, Jerome Apilan Robles

LSU Doctoral Dissertations

In order to investigate the effects of calcium carbonate and iron oxide on the thermal decomposition of solid fuels, we have constructed an isothermal flow reactor to perform experiments on the model compound catechol (ortho-dihydroxybenzene), a phenol-type compound representative of coal, wood and biomass. Calcium carbonate and iron oxide are inorganic components of coal and wood, which have demonstrated catalytic properties in thermal reactions and are commercially used to enhance the conversion of solid fuels. In this study, the effects of the inorganic solids on pyrolysis and combustion are conducted through identification and quantification of the products formed after subjecting …

Assessing A Hydrothermal Liquefaction Process Using Biomass Feedstocks, Jason S. Midgett

LSU Master's Theses

The need to reduce the United States dependence on foreign oil has never been greater. In the past decade emphasis has been placed on developing new and/or improved means to procure clean renewable energy. Liquefaction, which was developed for coal conversion over a century ago is one of these areas. Liquefaction used for biomass conversions to bio-oils is grouped under the thermochemical conversion (TCC) area of energy conversion methods along with gasification and pyrolysis. This thesis discusses liquefaction experiments conducted using varieties of Louisiana biomass feedstocks. Dairy manure collected from the Louisiana State University Dairy Farm in Baton Rouge, was …