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Potentially Massive And Global Non-Pyrogenic Production Of Condensed "Black" Carbon Through Biomass Oxidation, Aleksandar I. Goranov, Hongmei Chen, Jianshu Duan, Satish C. B. Myneni, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

With the increased occurrences of wildfires worldwide, there has been an increase in scientific interest surrounding the chemistry of fire-derived "black" carbon (BC). Traditionally, wildfire research has assumed that condensed aromatic carbon (ConAC) is exclusively produced via combustion, and thus, ConAC is equated to BC. However, the lack of correlations between ConAC in soils or rivers and wildfire history suggests that ConAC may be produced non-pyrogenically. Here, we show quantitative evidence that this occurs during the oxidation of biomass with environmentally ubiquitous hydroxyl radicals. Pine wood boards exposed to iron nails and natural weather conditions for 12 years yielded a …

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. …

A Foray Into Laboratory Scale Soil Incubations With Corn Stover And High Lignin Fermentation Byproduct, Michelle Wang

ENGS 88 Honors Thesis (AB Students)

As the production of biofuels increases to meet the demands of a growing low carbon economy, questions of sustainability surrounding its feedstock and waste streams have become increasingly relevant. In the biofuel production process, crop residues like corn stover are harvested from the field and converted to biofuels leaving generating a residue called high lignin fermentation byproduct (HLFB). From extensive process modelling in the literature, it is suggested that HLFB should be either combusted to fuel auxiliary conversion processes or returned to the soil in place of the crop residues that were harvested. Currently, there is little literature testing the …

Formation And Characterization Of Mechanochemically Generated Free Lignin Radicalsfrom Olive Seeds, Fatma Demi̇r

Turkish Journal of Chemistry

In this study, formation and quantification of mechanochemically generated free radicals of lignin were evaluated after the extraction of lignin from olive seeds and detailed lignin characterization was performed. Lignin was extracted from crushed olive seeds as an insoluble solid using Klason method. Isolated lignin was mechanochemically grinded under cryo conditions using Cryomill and particlesizes were determined by using Zeta Sizer, structural changes were followed by XRD and FTIR-ATR; thermal stabilities were tracked by TGA and DSC. In order to enable solubility demanding studies (such as 1H-NMR and GPC), acylation of lignin was accomplished. ESR measurements were completed to prove …

Lignin: A Likely Precursor Of A Significant Fraction Of Humic Substances Via Oxidative Transformations, Seyyedhadi Khatami

Chemistry & Biochemistry Theses & Dissertations

Lignin is a major component of decaying terrestrial vegetation in soils and has been arguably reported to contribute substantially to the formation of soil carbon humus, and natural dissolved organic matter (DOM). To better understand the process by which this humification occurs, lignin and lignin-derived monomers were subjected to both biotic and abiotic oxidation processes. Two well-known oxidative transformation strategies were employed. The first involved the fungal degradation of brown-rot degraded wood subjected to a white-rot fungus (Phanerochaete chrysosporium) whose enzymes are particularly effective in lignin degradation via enzymatic oxidation. This enzymatic attack was monitored by ultrahigh resolution …

Slow Pyrolysis Of Lignin Rich Residue From Lignocellulosic Biorefining Operations, Paola Giudicianni, Corinna Maria Grottola, Raffaele Ragucci

Pyroliq 2019: Pyrolysis and Liquefaction of Biomass and Wastes

Europe is committed to have a bio-based economy in 2030. It follows that a huge contribution of biorefinery products on the European demand for chemicals, energy, materials and fibers is expected in the near future. To be environmentally and economically sustainable, biorefinery will need to be flexible, versatile, energy and cost efficient [1]. In a lignocellulose based biorefinery, the sugar platform that leads to bioethanol and added-value products through biochemical processes represents a challenging option. After ethanol distillation a lignin reach residue (LRR) is produced and used as energy source. However, it is currently underutilized with about 60% more lignin …

Lignin-Derived Carbon And Nanocomposite Materials For Energy Storage Applications, Wenqi Li

Theses and Dissertations--Biosystems and Agricultural Engineering

With a growing demand for electrical energy storage materials, lignin-derived carbon materials have received increasing attention in recent years. As a highly abundant renewable carbon source, lignin can be converted to a variety of advanced carbon materials with tailorable chemical, structural, mechanical and electrochemical properties through thermochemical conversion (e.g. pyrolysis). However, the non-uniformity in lignin structure, composition, inter-unit linkages and reactivity of diverse lignin sources greatly influence lignin fractionation from plant biomass, the pyrolysis chemistry, and property of the resulting carbon materials.

To introduce a better use of lignocellulosic biomass to biofuels and co-products, it is necessary to find novel …

Value Added Products From Lignin And Biomass Derivatives, Chen Li

Civil & Environmental Engineering Theses & Dissertations

Pyrolysis is one of the traditional lignin and biomass utilization methods. The liquid products bio-oil and solid products bio-char are the main value-added products from lignin pyrolysis. Due to the narrow application and low quality, using the pyrolysis method to produce bio-oil and bio-char cannot bring sufficient economic benefits. In this dissertation, two methods were investigated to improve the quality of lignin bio-products.

Instead of direct pyrolysis, chemical activation (pyrolysis) was introduced in this dissertation. Compared to bio-char, the lignin chemical activation product lignin-activated-carbon has better economic value. With the best activation conditions, the lignin-activated-carbon produced a surface area of …

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, …

Carbon Sequestration Using Bio-Refinery Residues, Ondřej Mašek

Biochar: Production, Characterization and Applications

Biomass consists of four main constituents, cellulose, hemicellulose, lignin and minerals. The first two, are the key targets for various conversion processes producing biofuels and chemicals, leaving behind different forms of lignin, depending on extraction process used.

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Production And Characterization Of Slow Pyrolysis Biochar From Lignin-Rich Digested Stillage From 2nd Generation Bioethanol Production, Frederik Ronsse, Dane Dickinson, Wolter Prins

Biochar: Production, Characterization and Applications

Lignin-rich stillage from 2nd generation bioethanol production is a unique feedstock for slow pyrolysis and biochar production, as it contains high amounts of lignin (62 wt. % d.b) and ash (9.97 wt. % d.b) next to some residual cellulose and hemicellulose. As lignin is known to result in higher char and char-C yields compared to regular lignocellulosic feedstock, the suitability of a lignin-containing residue, obtained from a 2nd generation bio-ethanol pilot run using short rotation poplar, was subjected to anaerobic digestion for biogas production followed by slow pyrolysis of the digestate for the production of biochar.

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Lignin Transformation And Characterization Of Pyrolytic Products, Eric Amo Boakye

Electronic Theses and Dissertations

Lignocellulosic materials derived from plants have the ability to serve as feedstocks in place of depleting petroleum and coal for production of fuels and chemicals. Lignin forms about 30% of lignocellulosic material, and is the second most abundant non-fossil organic carbon source in the biosphere. However, it is often treated as waste or, in some instances, burned to supply energy. Developing an efficient and environmentally benign method to convert lignin to high value-added aromatic monomers (e.g., guaiacol, vanillin, acetovanillone, and eugenol) for synthesis of polymers is of interest. Mineral bases, such as NaOH and CsOH, or supported-metal catalysts (Pt, Ru, …

Renewable Carbon From Lignin Biomass And Its Electrode And Catalyst Applications In Batteries, Supercapacitors, And Fuel Cells, Muslum Demir

Theses and Dissertations

Over the last century, almost all of the carbon materials developed for the energy industry are derived from fossil fuels. The growing global concerns about energy needs, fossil fuels consumption, and the related environmental issues have motived scientists to find new, green and sustainable energy resources such as the wind, solar and biomass energy. Essentially, biomass-derived materials can be utilized in energy storage and conversion devices such as Li-ion batteries, fuel cells, and supercapacitors. Among the biomass resources, lignin is a high volume byproduct from the pulp and paper industry and is currently burned to generate electricity and steam. The …

Synthesis And Characterization Of Carbon-Based Nanomaterials From Lignin, Xuefeng Zhang

Theses and Dissertations

The main objective of this research was to develop a catalytic thermal conversion process for production of carbon-based nanomaterials (CNs) from kraft lignin. Four specific objectives were to: (1) understand the structural evolution of kraft lignin during its thermal treatment process; (2) investigate effects of temperature, and iron catalyst loading and morphology on the catalytic thermal conversion of kraft lignin to CNs, understand lignin catalytic thermal conversion mechanism; (3) explore potential applications of CNs synthesized from kraft lignin as an adsorbent for lead removing from contaminated water; (4) and propose effective methods for graphene material characterization. Experimental results indicated that …

Engineering Plant Biomass Lignin Content And Composition For Biofuels And Bioproducts, Cassie Marie Welker, Vimal Kumar Balasubramanian, Carloalberto Petti, Krishan Mohan Rai, Seth Debolt, Venugopal Mendu

Horticulture Faculty Publications

Lignin is an aromatic biopolymer involved in providing structural support to plant cell walls. Compared to the other cell wall polymers, i.e., cellulose and hemicelluloses, lignin has been considered a hindrance in cellulosic bioethanol production due to the complexity involved in its separation from other polymers of various biomass feedstocks. Nevertheless, lignin is a potential source of valuable aromatic chemical compounds and upgradable building blocks. Though the biosynthetic pathway of lignin has been elucidated in great detail, the random nature of the polymerization (free radical coupling) process poses challenges for its depolymerization into valuable bioproducts. The absence of specific …

Application Of Pyrolysis-Gc/Ms To The Study Of Biomass And Biomass Constituents, Anne E. Ware

Theses and Dissertations--Chemistry

Fast pyrolysis, the rapid thermal decomposition of organic material in the absence of oxygen, is a process that can be used to convert biomass into liquid fuels and chemicals. When performed at the micro-scale, pyrolysis is useful for characterizing biomass structure, as well as determining the pyrolysis products that can be generated from specific biomass feedstocks. Indeed, microscale pyrolysis coupled with on-line analysis of the pyrolysis vapors by GC/MS, so-called pyrolysis-GC/MS (Py-GC/MS), is a technique that can be used to characterize the structure and composition of the various components of lignocellulosic and microalgal biomass based on their pyrolysate distributions. Pyrolysates …