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Examining The Relationship Between Lignocellulosic Biomass Structural Constituents And Its Flow Behavior, Ekramul Haque Ehite

Doctoral Dissertations

Lignocellulosic biomass material sourced from plants and herbaceous sources is a promising substrate of inexpensive, abundant, and potentially carbon-neutral energy. One of the leading limitations of using lignocellulosic biomass as a feedstock for bioenergy products is the flow issues encountered during biomass conveyance in biorefineries. In the biorefining process, the biomass feedstock undergoes flow through a variety of conveyance systems. The inherent variability of the feedstock materials, as evidenced by their complex microstructural composition and non-uniform morphology, coupled with the varying flow conditions in the conveyance systems, gives rise to flow issues such as bridging, ratholing, and clogging. These issues …

Understanding Lignin’S Fast Pyrolysis Through Examination Of The Thermolysis Mechanisms Of Model Oligomers, Ross Wesley Houston

Doctoral Dissertations

The lignocellulosic biorefinery is a visionary concept that endeavors to provide an alternative to fossil-based refineries by producing biobased fungible fuels and specialty chemicals almost exclusively derived currently from petroleum refineries. This vision of the lignocellulosic biorefinery can only be realized if all fractions of lignocellulosic biomass are efficiently deconstructed and valorized to generate a diverse portfolio of products to sustain it against market vicissitudes. Of the three main structural constituents of lignocellulosic biomass (i.e., cellulose, hemicellulose, and lignin), lignin is underutilized despite being the most abundant renewable source of aromatic platform chemicals, representing a growing 250 billion dollar market. …

Co2 Adsorption Using Mg-Mof-74/Activated Biochar Composites Produced From The Pyrolysis Of Lignocellulosic Biomass, Conner Brosdan Pope

Masters Theses

Adsorption is a promising carbon capture and storage (CCS) technology with porous solids like activated biochar (AB), graphene oxides (GO), and metal-organic frameworks (MOF) exhibiting different advantages related to separating carbon dioxide (CO₂) from gas mixtures. Accordingly, the synthesis of MOF/GO composites demonstrates synergism between CO₂ adsorption-driving physicochemical characteristics of MOFs and GOs. However, the synthesis of MOF/AB composites has not been explored in the literature to date even though AB shares many physical and chemical similarities with GO. This research project aimed to synthesize MOF/AB composites with appropriate physicochemical characteristics and CO₂ adsorption capacities for …

Fate And Transport Of 17beta-Estradiol Beneath Animal Waste Holding Ponds, Lori A. Gibson

Masters Theses

Steroidal hormones, such as 17beta-estradiol (E2) and its primary metabolite, estrone (E1), are prevalent in animal waste and are a common subject of study due to potential soil, stream, and groundwater contamination. These particular hormones are labeled as Endocrine Disrupting Chemicals (EDCs) because of their developmental effects in reptiles and amphibians. Dairy waste at concentrated animal feeding operations (CAFOs) is typically stored in a waste pond. Even though these waste ponds are regulated to include a soil liner with a minimal hydraulic conductivity to limit leaching, previous studies have traced stream and groundwater contamination from waste ponds. This research included …

The Effects Of Biochar Amendment To Soil On Bioenergy Crop Yield And Biomass Composition, Charles Warren Edmunds

Masters Theses

This thesis research aims to improve the understanding of how pyrolysis of native feedstocks and biochar application to soil can be utilized to improve soil fertility, crop yield, and sequester carbon in the Southeastern U.S. An emphasis was placed on understanding how the pyrolysis conditions and feedstock material influence biochar characteristics and what effects biochar amendment has on soil and plant growth and composition.

Biochars were produced from switchgrass and pine wood feedstocks via fast pyrolysis at 450, 600, and 800 ˚C with a continuous auger pyrolysis system. Switchgrass-derived biochars had higher ash content, and as observed by elemental analysis, …