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Physical Sciences and Mathematics

2018

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Evaluation Of Three Forest-Based Bioenergy Development Strategies In The Inland Northwest, United States, Jill Moroney Nov 2018

Evaluation Of Three Forest-Based Bioenergy Development Strategies In The Inland Northwest, United States, Jill Moroney

Human-Environment Systems Research Center Faculty Publications and Presentations

In this article, we compare three bioenergy scenarios that use woody biomass from US Inland Northwest forests. The scenarios are based on current bioenergy research, development efforts, and stakeholder input. They include a small-scale system that produces drop-in transportation biofuel and biochar, a large, regional system that produces bio-aviation fuel, and a midsized pellet production system. We modeled woody biomass harvest, processing, and transportation, and then evaluated profitability and potential socioeconomic impacts to determine the overall viability of each strategy. Through interviews, we found widespread stakeholder support for all three scenarios. Wood-pellet production was profitable and feasible with current prices …


A Novel Shortwave Infrared Proximal Sensing Approach To Quantify The Water Stability Of Soil Aggregates, Azadeh Gholoubi, Hojat Emami, Scott B. Jones, Markus Tuller Oct 2018

A Novel Shortwave Infrared Proximal Sensing Approach To Quantify The Water Stability Of Soil Aggregates, Azadeh Gholoubi, Hojat Emami, Scott B. Jones, Markus Tuller

Plants, Soils, and Climate Faculty Publications

Soil structure and aggregate stability (AS) are critical soil properties affecting water infiltration, root growth, and resistance to soil and wind erosion. Changes in AS may be early indicators of soil degradation, pointing to low organic matter (OM) content, reduced biological activity, or poor nutrient cycling. Hence, efficient and reliable AS measurement techniques are essential for detection, management, and remediation of degraded soil resources. Here we quantify soil AS by developing a novel proximal sensing technique based on shortwave infrared (SWIR) reflectance measurements. The novel approach is similar to the well-documented high energy moisture characteristic (HEMC) method, which yields a …


Using Renewable Portfolio Standards To Accelerate Development Of Negative Emissions Technologies, Anthony E. Chavez Oct 2018

Using Renewable Portfolio Standards To Accelerate Development Of Negative Emissions Technologies, Anthony E. Chavez

William & Mary Environmental Law and Policy Review

As society continues to emit greenhouse gases, the likelihood of dangerous climate change occurring increases. Indeed, most analyses project that we must utilize negative emission technologies (“NETs”) to avoid dangerous warming. Even the Paris Agreement anticipates the implementation of such carbon dioxide (“CO2”) removal technologies. Unfortunately, NETs are not ready for large-scale deployment. In many instances, their technologies remain uncertain; in others, their ability to operate at the scale required is unknown. Other uncertainties, including their costs, effectiveness, and environmental impacts have yet to be determined.

A means to accelerate the development and implementation of NETs is a …


Removal Efficiencies, Uptake Mechanisms And Competitive Effects Of Copper And Zinc In Various Stormwater Filter Media, Emily Heleva-Ponaski Sep 2018

Removal Efficiencies, Uptake Mechanisms And Competitive Effects Of Copper And Zinc In Various Stormwater Filter Media, Emily Heleva-Ponaski

Dissertations and Theses

Polluted stormwater, if not treated, can compromise water quality throughout our hydrologic cycle, adversely affecting aquatic ecosystems. Common stormwater pollutants, copper and zinc, have been identified as primary toxicants in multiple freshwater and marine environments. For small-scale generators, stormwater management can be cumbersome and implementation of common BMPs impractical thus catch basins are popular though not the most environmentally conscious and sustainable option. This study aims to characterize the potential of a mobile media filter operation for the treatment and on-site recycling of catch basin stormwater. The removal capacities of various commercially available filter media (e.g. a common perlite; Earthlite™, …


Plant Stimuli-Responsive Biodegradable Polymers For The Use In Timed Release Fertilizer Coatings, Spencer Heuchan Aug 2018

Plant Stimuli-Responsive Biodegradable Polymers For The Use In Timed Release Fertilizer Coatings, Spencer Heuchan

Electronic Thesis and Dissertation Repository

The use of nitrogen-based fertilizers continues to accelerate with human population growth and increases in global food requirements. Enhanced efficiency fertilizers (EEFs) have been developed to improve the synchronization between nutrient supply and crop nutrient demand. However, many of the current controlled release fertilizers are coated with non-degradable polymers that contribute to accumulation of microplastics within ecosystems. This thesis describes research towards the development of a new class of fertilizer coatings using a self-immolative polymer known as poly (ethyl glyoxylate) (PEtG). PEtG itself does not have suitable properties to produce a viable coating but once blended with another degradable polyester …


Water Treatment Residual Coated Wood Mulch For Mitigation Of Toxic Metals And Phosphate From Polluted Urban Stormwater Runoff, Hanieh Soleimanifar Aug 2018

Water Treatment Residual Coated Wood Mulch For Mitigation Of Toxic Metals And Phosphate From Polluted Urban Stormwater Runoff, Hanieh Soleimanifar

Theses, Dissertations and Culminating Projects

Polluted urban runoff as a primary non-point pollution source poses a serious threat to urban human and ecological health. Various urban runoff pollutants challenge the exiting stormwater treatment systems. To support the development of a sound and sustainable urban stormwater management, this dissertation targets at transforming a common landscaping practice, i.e. mulching, into a new stormwater treatment technology through coating aluminum water treatment residual (Al-WTR) on the surface of wood mulch chips. WTR is an industrial waste produced from drinking water treatment plants and primarily comprises amorphous aluminum (hydr)oxides. The Al-WTR coating on the modified wood mulch enables the adsorption …


Differential Responses Of Carbon-Degrading Enzyme Activities To Warming: Implications For Soil Respiration, Ji Chen, Yiqi Luo, Pablo García-Palacios, Junji Cao, Marina Dacal, Xuhui Zhou, Jianwei Li, Jianyang Xia, Shuli Niu, Huiyi Yang, Shelby Shelton, Wei Guo, Kees Jan Van Groenigen Jul 2018

Differential Responses Of Carbon-Degrading Enzyme Activities To Warming: Implications For Soil Respiration, Ji Chen, Yiqi Luo, Pablo García-Palacios, Junji Cao, Marina Dacal, Xuhui Zhou, Jianwei Li, Jianyang Xia, Shuli Niu, Huiyi Yang, Shelby Shelton, Wei Guo, Kees Jan Van Groenigen

Agricultural and Environmental Sciences Faculty Research

Extracellular enzymes catalyze rate-limiting steps in soil organic matter decomposition, and their activities (EEAs) play a key role in determining soil respiration (SR). Both EEAs and SR are highly sensitive to temperature, but their responses to climate warming remain poorly understood. Here, we present a meta-analysis on the response of soil cellulase and ligninase activities and SR to warming, synthesizing data from 56 studies. We found that warming significantly enhanced ligninase activity by 21.4% but had no effect on cellulase activity. Increases in ligninase activity were positively correlated with changes in SR, while no such relationship was found for cellulase. …


Thermodynamic And Kinetic Study Of The Removal Of Cu2+ And Pb2+ Ions From Aqueous Solution Using Fe7s8 Nanomaterial, Jesus Cantu, Diego F. Gonzalez, Yvette Cantu, Thomas Eubanks, Jason Parsons Jul 2018

Thermodynamic And Kinetic Study Of The Removal Of Cu2+ And Pb2+ Ions From Aqueous Solution Using Fe7s8 Nanomaterial, Jesus Cantu, Diego F. Gonzalez, Yvette Cantu, Thomas Eubanks, Jason Parsons

Chemistry Faculty Publications and Presentations

In the present study, pyrrhotite (Fe7S8) was investigated for the removal of Pb2+ and Cu2+ ions from aqueous solution. The Fe7S8 material was prepared through a solvothermal method and was characterized using XRD. The average particle size for the nanomaterial was determined to be 29.86 ± 0.87 nm using XRD analysis and Scherrer's equation. Batch studies were performed to investigate the effects of pH, time, temperature, interfering ions, and the binding capacity of Pb2+ and Cu2+ ions to the Fe7S8 nanomaterial. During the pH profile studies, the optimum pH for the binding of Pb2+ and Cu2+ was determined to be …


Full Issue 47(2) Jun 2018

Full Issue 47(2)

International Journal of Speleology

No abstract provided.


Glyphosate In Soils: Retention, Transport, And Effect Of Phosphate, Joshua Padilla Jun 2018

Glyphosate In Soils: Retention, Transport, And Effect Of Phosphate, Joshua Padilla

LSU Master's Theses

Glyphosate [N-(phosphonomethyl) glycine)] (GPS) is currently the most commonly used herbicide worldwide, and is generally considered as immobile in soils. However, numerous reports of the environmental occurrence of the herbicide coupled with recent evidence of human toxicity require further investigation as to the behavior of GPS in the soil environment. The objectives of this study were to quantify GPS sorption and mobility in two Louisiana agricultural soils with varying physiochemical properties; Commerce silt loam and Sharkey clay. Results of batch sorption studies indicated a high affinity of both soils for solvated GPS, with 24-hour Freundlich partitioning coefficients of 158 and …


Alternatives To Traditional Agricultural Biomass Burning In Napa Valley, Daniela Bazán May 2018

Alternatives To Traditional Agricultural Biomass Burning In Napa Valley, Daniela Bazán

Master's Projects and Capstones

Vineyard pruning residues and removed vines create an annual biomass waste issue for growers in Napa Valley. Traditionally this agricultural biomass waste is eliminated by open burning, but with increasing public health and climate change concerns as well as public outcry over large smoke plumes in picturesque Napa Valley, it is necessary to evaluate the alternatives to traditional agricultural biomass burning. The purpose of this study is to evaluate and compare these alternatives and to determine the most sustainable and practicable alternatives for use in Napa Valley. The alternatives to traditional agricultural biomass burning analyzed in this study include low-smoke …


Biochar From Waste Banana Peels As Growth Promoter For Holy Basil (Ocimum Tenuiflorum) And Chili Pepper (Capsicum Annuum), Regina C. So, N Tan May 2018

Biochar From Waste Banana Peels As Growth Promoter For Holy Basil (Ocimum Tenuiflorum) And Chili Pepper (Capsicum Annuum), Regina C. So, N Tan

Chemistry Faculty Publications

Biochars are porous materials prepared by combustion of biomass under the presence of low oxygen levels. Its application as soil fertilizer has been shown to have positive effects on the plants by increasing the fertility and raising the soil pH, increasing nutrient cycling and moisture holding capacity, improving cation exchange capacity, and reducing the amount of pesticides and nutrients leaching to the surface and ground water (Laird 2008, Speratti 2017). In this study, waste banana peels of the Lakatan variety (Musa x paradisiaca) were pyrolized at temperatures 300, 400, 500 and 700 °C, the resulting basic char were obtained at …


Environmental Dynamics Of Dissolved Organic Matter And Dissolved Black Carbon In Fluvial Systems: Effects Of Biogeochemistry And Land Use, J. Alan Roebuck Jr. May 2018

Environmental Dynamics Of Dissolved Organic Matter And Dissolved Black Carbon In Fluvial Systems: Effects Of Biogeochemistry And Land Use, J. Alan Roebuck Jr.

FIU Electronic Theses and Dissertations

Black carbon (BC) is an organic residue formed primarily from biomass burning (e.g., wildfires) and fossil fuel combustion. Until recently, it was understood that BC was highly recalcitrant and stabilized in soils over millennial scales. However, a fraction of the material can be solubilized and transported in fluvial systems as dissolved BC (DBC), which represents on average 10% of the global export of dissolved organic carbon (DOC) from rivers to coastal systems. The composition of DBC controls its reactivity, and it has been linked with a variety of in-stream processes that induce both carbon sequestration and evasion of CO₂ from …


Sustainable Agriculture: Integration Of Aquaponics At Punta Leona Hotel And Club In Costa Rica, Cailin Sierra Dyer, Paris Riley Smith May 2018

Sustainable Agriculture: Integration Of Aquaponics At Punta Leona Hotel And Club In Costa Rica, Cailin Sierra Dyer, Paris Riley Smith

Senior Honors Projects, 2010-2019

Sustainable agriculture is becoming an increasingly important method of food production. As human populations continue to grow, attendant food demand has been increasingly met via agribusiness, including monoculture crop production and factory farming. As is well documented, the rise of agribusiness has led to resource degradation and declining stocks on which “sustainable agriculture” relies. This paper describes a local attempt to re-establish “sustainable agriculture” through the development of an aquaculture system that mimics a naturally occurring cycle that integrates fish and plants. The system was constructed over a three-week period in Punta Leona, Costa Rica. First, the ground was cleared …


Synthesis And Characterization Of Biodiesel Fuels From Furfuryl Alcohol And Spent Coffee Grounds, Amanda Raley May 2018

Synthesis And Characterization Of Biodiesel Fuels From Furfuryl Alcohol And Spent Coffee Grounds, Amanda Raley

Electronic Theses and Dissertations

ABSTRACT

Biodiesel can be synthesized using several different triacylglycerides, alcohols, and catalysts. In this study, fatty acid methyl esters (FAMEs) and fatty acid ethyl esters (FAEEs) were produced from their respective alcohols and coffee oil, using either a basic (K2CO3) catalyst or an acidic catalyst (H2SO4). Fatty acid furfuryl esters (FAFurEs) were produced using commercially-purchased cooking oils (canola, olive, corn, sunflower, and peanut) with furfuryl alcohol, a basic (K2CO3) catalyst, a co-solvent (THF), and an ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate). All samples were produced using either conventional heating methods …


Removal Of Chromium(Vi) And Chromium(Iii) Ions From Aqueous Solution Using Bio-Char Generated From Agricultural Waste Products, Diego Fernando Gonzalez May 2018

Removal Of Chromium(Vi) And Chromium(Iii) Ions From Aqueous Solution Using Bio-Char Generated From Agricultural Waste Products, Diego Fernando Gonzalez

Theses and Dissertations

Heavy metals are one of the most persistent and prevalent contaminants in the aquatic environment. The removal of chromium from aqueous solution, especially in the hexavalent form is difficult. New technologies, techniques and/or new materials have been designed in order to effectively and efficiently remove chromium from the aqueous environment. The project focuses on the comparison of the effects of pH, time, temperature, binding capacity on bio-char’ generated from agricultural waste produces vs an amino modified derivative of the bio-char. Pineapple skins were dried, ground, sieved, and pyrolyzed to produce a bio-char material. The bio-char was analyzed using FTIR to …


Performance Assessment Of Solid State Anaerobic Digestion Of Poultry Litter, Mason Puckett May 2018

Performance Assessment Of Solid State Anaerobic Digestion Of Poultry Litter, Mason Puckett

Biological and Agricultural Engineering Undergraduate Honors Theses

The disposal of poultry litter can exert an economic and environmental burden to the agriculture community. As a result, it is desirable to reduce the amount of waste and recover resources from the waste. This study focuses on the construction and preliminary testing of a laboratory scale (20 L) solid state anaerobic digester (AD) fed with dry poultry litter. Glucose was added in addition to the poultry litter to achieve the appropriate C:N ratio to support the growth of anaerobic microorganisms. The AD was first fed every 4 days at 4 g VS/L/feeding for 24 days, rested (no feeding) for …


Construction Of A Pen-Scale Methane Collection System And Dietary Strategies For Methane Mitigation From Growing And Finishing Cattle, Thomas Winders Apr 2018

Construction Of A Pen-Scale Methane Collection System And Dietary Strategies For Methane Mitigation From Growing And Finishing Cattle, Thomas Winders

Department of Animal Science: Dissertations, Theses, and Student Research

Methane production from ruminants has been researched for many years because it has a global warming potential 25x that of carbon dioxide, meaning that mitigating smaller amounts of methane can have a large environmental impact. Research has focused on individual animal methane measurements, but the literature lack in industry-scale measurements. For that reason, the methane barn was built to evaluate dietary strategies on pens of cattle rather than on individual animals. In order to test the methane barn capabilities, an experiment designed to produce differences in methane production was conducted. Cattle received the same growing diet, at either ad-libitum access …


Effects Of Enhanced Efficiency Nitrogen Fertilizers On Agronomic Parameters And Loss Pathways In The Subtropical Mississippi Delta Region, Scott Michael Pensky Apr 2018

Effects Of Enhanced Efficiency Nitrogen Fertilizers On Agronomic Parameters And Loss Pathways In The Subtropical Mississippi Delta Region, Scott Michael Pensky

LSU Master's Theses

Minimizing nitrogen (N) loss is critical for improving N use efficiency (NUE) in crop production and reducing its effects on the environment. Management practices such as seasonal application timing of N fertilizers and the addition of enhanced efficiency N fertilizers (EENFs) were investigated for the high N requirement of the two most common cereal crops globally, corn (Zea mays L.) and wheat (Triticum aestivum L.), in the subtropical climate of Louisiana. Field research was established during the 2016 and 2017 seasons at the LSU Agricultural Center’s Dean Lee and Central research stations to examine the effect of different EENFs and …


Production And Composition Of Pyrogenic Dissolved Organic Matter From A Logical Series Of Laboratory-Generated Chars, Kyle W. Bostick, Andrew R. Zimmerman, Andrew S. Wozniak, Siddhartha Mitra, Patrick G. Hatcher Apr 2018

Production And Composition Of Pyrogenic Dissolved Organic Matter From A Logical Series Of Laboratory-Generated Chars, Kyle W. Bostick, Andrew R. Zimmerman, Andrew S. Wozniak, Siddhartha Mitra, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Though pyrogenic carbon (pyC) has been assumed to be predominantly stable, degradation and transfers of pyC between various pools have been found to influence its cycling and longevity in the environment. Dissolution via leaching may be the main control on loss processes such as microbial or abiotic oxidation, mineral sorption, or export to aquatic systems. Yet, little is known about the controls on pyrogenic dissolved organic matter (pyDOM) generation or composition. Here, the yield and composition of pyDOM generated through batch leaching of a thermal series of oak and grass biochars, as well as several non-pyrogenic reference materials, was compared …


Design Improvements To Sulfate-Reducing Bioreactors For Mine-Influenced Stream Remediation In Cold Climates, Katrina Moreira Apr 2018

Design Improvements To Sulfate-Reducing Bioreactors For Mine-Influenced Stream Remediation In Cold Climates, Katrina Moreira

Graduate Theses & Non-Theses

Mine-influenced water (MIW), a waste water product containing heavy metals and sulfates, is a significant pollution source to waters in Montana. Implementing a low cost, passive treatment system, such as a sulfate-reducing bioreactor (SRBR), is desired for remediation of streams influenced by heavy metals in remote locations. SRBR systems operate by using organic matter and sulfate-rich water to precipitate and immobilize dissolved heavy metals. Sulfate-reducing bacteria utilize the organic matter as an electron donor to convert sulfate to sulfide, and then sulfide in the bioreactor is utilized to precipitate heavy metals. Under ideal operating conditions, SRBR systems can remove >98% …


New Records Of Guano-Associated Minerals From Caves In Northwestern Borneo, Donald A. Mcfarlane, Joyce Lundberg Mar 2018

New Records Of Guano-Associated Minerals From Caves In Northwestern Borneo, Donald A. Mcfarlane, Joyce Lundberg

International Journal of Speleology

Recent studies of ancient bat guano deposits in the caves of Gunung Mulu National Park and Niah National Park, Sarawak, Malaysia, have resulted in noteworthy records of phosphate minerals from these environments, including variscite, nano-particulate silica, fluorapatite, and niter.


Community-Level Plant–Soil Feedbacks Explain Landscape Distribution Of Native And Non-Native Plants, Andrew Kulmatiski Jan 2018

Community-Level Plant–Soil Feedbacks Explain Landscape Distribution Of Native And Non-Native Plants, Andrew Kulmatiski

Wildland Resources Faculty Publications

Plant–soil feedbacks (PSFs) have gained attention for their potential role in explaining plant growth and invasion. While promising, most PSF research has measured plant monoculture growth on different soils in short-term, greenhouse experiments. Here, five soil types were conditioned by growing one native species, three non-native species, or a mixed plant community in different plots in a common-garden experiment. After 4 years, plants were removed and one native and one non-native plant community were planted into replicate plots of each soil type. After three additional years, the percentage cover of each of the three target species in each community was …


Evaluating The Effectiveness Of Biochar For Treating Wsu Parking Lot Runoff, Alan-Christian Thomas Jan 2018

Evaluating The Effectiveness Of Biochar For Treating Wsu Parking Lot Runoff, Alan-Christian Thomas

Research Opportunities for Engineering Undergraduates (ROEU) Program 2017-18

Various pollutants including pesticides, herbicides, automotive fluids, and excess nutrients from fertilizers are found in high concentrations in urban runoff. There are many technologies that can be used to control and redirect the water flow such as retention basins, constructed wetlands, and rain gardens; however, these methods are specifically focused on controlling water and not necessarily the nutrients and contaminants in the water. There has recently been an increased interest in the potential for using additional materials (e.g., compost, charcoal) to enhance the pollution treatment ability by either adding them to the soil or by engineering prefilters to remove pollutants …


Oxidation Of Β-O-4 Lignin Model Compounds And Application To Lignin Linkage Degradation Facilitated By Mechanochemical Treatment And Two-Step Oxidative Depolymerization, Soledad G. Yao Jan 2018

Oxidation Of Β-O-4 Lignin Model Compounds And Application To Lignin Linkage Degradation Facilitated By Mechanochemical Treatment And Two-Step Oxidative Depolymerization, Soledad G. Yao

Theses and Dissertations--Chemistry

The oxidation of lignin model compounds was studied in conventional solvents in parallel with oxidations in ionic liquid solvents. Catalyst systems were investigated in ionic liquid solvents to determine how reaction rates and the selectivity for benzylic carbon oxidation were affected. Oxidation rates were often lower in ionic liquids than in conventional solvents ‒ as indicated by lower conversion in a standard reaction time ‒ likely due, at least in part, to the higher viscosity of ionic liquids. Mechano chemical treatment of Indulin AT kraft lignin by ball milling with KOH and toluene produced significant carbonyl functionality, among other changes. …


Water-Energy-Food Nexus Stakeholder Information Sharing And Engagement Workshop, Rudolph A. Rosen, Bassel Daher, Rabi Mohtar Jan 2018

Water-Energy-Food Nexus Stakeholder Information Sharing And Engagement Workshop, Rudolph A. Rosen, Bassel Daher, Rabi Mohtar

Water Resources Science and Technology Book and E-Book Publications and Reports

On January 10, 2018, the Texas A&M University System Water-Energy-Food Initiative held the Water-Energy-Food Nexus Stakeholder Information Sharing and Engagement Workshop on the campus of Texas A&M University-San Antonio. The workshop involved over 70 stakeholders drawn from the water, energy, and food sectors in San Antonio and surrounding region. Stakeholders attending the workshop heard presentations on the status of San Antonio Case Study pilot projects and other WEF nexus work. Facilitated small-group sessions were held at the workshop to obtain stakeholder input on research questions to be asked, and on limitations and opportunities for stakeholder engagement on WEF nexus-related work …


Microstructural And Associated Chemical Changes During The Composting Of A High Temperature Biochar: Mechanisms For Nitrate, Phosphate And Other Nutrient Retention And Release, Stephen D. Joseph, Claudia Kammann, Jessica Shepherd, Pellegrino Conte, Hans-Peter Schmidt, Nikolas Hagemann, Anne Rich, Christopher Marjo, Jessica Allen, Paul R. Munroe, David R. G Mitchell, Scott Donne, Kurt Spokas, Ellen Graber Jan 2018

Microstructural And Associated Chemical Changes During The Composting Of A High Temperature Biochar: Mechanisms For Nitrate, Phosphate And Other Nutrient Retention And Release, Stephen D. Joseph, Claudia Kammann, Jessica Shepherd, Pellegrino Conte, Hans-Peter Schmidt, Nikolas Hagemann, Anne Rich, Christopher Marjo, Jessica Allen, Paul R. Munroe, David R. G Mitchell, Scott Donne, Kurt Spokas, Ellen Graber

Australian Institute for Innovative Materials - Papers

Recent studies have demonstrated the importance of the nutrient status of biochar and soils prior to its inclusion in particular agricultural systems. Pre-treatment of nutrient-reactive biochar, where nutrients are loaded into pores and onto surfaces, gives improved yield outcomes compared to untreated biochar. In this study we have used a wide selection of spectroscopic and microscopic techniques to investigate the mechanisms of nutrient retention in a high temperature wood biochar, which had negative effects on Chenopodium quinoa above ground biomass yield when applied to the system without prior nutrient loading, but positive effects when applied after composting. We have compared …


Development And Evaluation Of Post-Production Oxygenation Techniques For The Augmentation Of Biochar, Matthew David Huff Jan 2018

Development And Evaluation Of Post-Production Oxygenation Techniques For The Augmentation Of Biochar, Matthew David Huff

Chemistry & Biochemistry Theses & Dissertations

Biochar is the carbon rich solid by-product of biomass pyrolysis. Interest in biochar can be broken down to several main categories: use as a carbon sequestration agent, use as a medium for the removal via adsorption of unwanted materials in wastewater, and as a soil amendment for the increase of cation exchange capacity (CEC). In order to generate a biochar which is stable enough for carbon sequestration, higher temperature pyrolysis must be used in order to ensure a lower O:C ratio in order to increase the half-life of biochar in soil. This dissertation addresses the evaluation of biochars made from …


Surface Oxygenation Of Biochar Through Ozonization For Dramatically Enhancing Cation Exchange Capacity, Matthew D. Huff, Sarah Marshall, Haitham A. Saeed, James Weifu Lee Jan 2018

Surface Oxygenation Of Biochar Through Ozonization For Dramatically Enhancing Cation Exchange Capacity, Matthew D. Huff, Sarah Marshall, Haitham A. Saeed, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

Background

Biochar cation exchange capacity (CEC) is a key property that is central to biochar environmental applications including the retention of soil nutrients in soil amendment and removal of certain pollutants in water-filtration applications.

Results

This study reports an innovative biochar-ozonization process that dramatically increases the CEC value of biochars by a factor of 2. The ozonized biochars also show great improvement on adsorption of methylene blue by as much as a factor of about 5. In this study, biochar samples treated with and without ozone were analyzed by means of pH and CEC assays, water field capacity measurement, elemental …


Lignin Depolymerization: Mechanistic Analysis, Optimization And Application, Eric Michael Nagel Jan 2018

Lignin Depolymerization: Mechanistic Analysis, Optimization And Application, Eric Michael Nagel

Electronic Theses and Dissertations

Lignin is the most abundant aromatic biopolymer and is a potential source for phenolic chemical feedstocks. Lignin is composed of phenolic units connected by more than eight different linkages, the most common being β-O-4 which constitutes 50-60%. The hydrothermal decomposition of a guaiacol based β-O-4 lignin dimer was studied under neutral and basic conditions to elucidate the mechanism of β-O-4 bond cleavage and the formation of downstream products. Phenol-carbonyl condensation and vinyl-ether formation were shown to be the primary causes for low monomer yields under the tested conditions. Three Ni catalyst systems, Ni/C + H2, Ni/C-Zn, and Ni/Zn, …