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Commercialization of New Carbon Fiber Materials Based on Sustainable Resources for Energy Applications

Description: Oak Ridge National Laboratory (ORNL) and GrafTech International have collaborated to develop and demonstrate the performance of high temperature thermal insulation prototypes made from lignin-based carbon fibers. This project will potentially lead to the first commercial application of lignin-based carbon fibers (LBCF). The goal of the commercial application is to replace expensive, Chinese-sourced isotropic pitch carbon fibers with lower cost carbon fibers made from a domestically sourced, bio-derived (renewable) feedstock. LBCF can help recapture jobs that were previously exported to China while resolving a supply chain vulnerability and reducing the production cost for GrafTech s high temperature thermal insulation. The performance of the LBCF prototypes was measured and found to be comparable to that of the current commercial product. During production of the insulation prototypes, ORNL and GrafTech demonstrated lignin compounding/pelletization, fiber production, heat treatment, and compositing at scales far surpassing those previously demonstrated in LBCF R&D or production. A plan was developed for the commercialization of LBCF thermal insulation, with key milestones including qualification of multiple scalable lignin sources in 2013, tons-scale production and field testing by customers in 2014, and product launch as soon thereafter as production capabilities can be constructed and commissioned.
Date: March 1, 2013
Creator: Eberle, Cliff; Webb, Daniel C; Albers, Tracy & Chen, Chong
Partner: UNT Libraries Government Documents Department

An “ideal lignin” facilitates full biomass utilization

Description: This article describes the ideal nature of the Catechyl lignin (C-lignin) via a revised compositional characterization of the vanilla seed coat fiber, new features of the C-lignin's reactivity and stability, and successful attempts at converting it to monomers in near-quantitative yields.
Date: September 28, 2018
Creator: Li, Yanding; Shuai, Li; Kim, Hoon; Hussain Motagamwala, Ali; Mobley, Justin K.; Yue, Fengxia et al.
Partner: UNT College of Arts and Sciences

Design of Bioinspired Conductive Smart Textile

Description: Electrically conductive fabrics are one of the major components of smart textile that attracts a lot of attention by the energy, medical, sports and military industry. The principal contributors to the conductivity of the smart textiles are the intrinsic properties of the fiber, functionalization by the addition of conductive particles and the architecture of fibers. In this study, intrinsic properties of non-woven carbon fabric derived from a novel linear lignin, poly-(caffeyl alcohol) (PCFA) discovered in the seeds of the vanilla orchid (Vanilla planifolia) was investigated. In contrast to all known lignins which comprise of polyaromatic networks, the PCFA lignin is a linear polymer. The non-woven fabric was prepared using electrospinning technique, which follows by stabilization and carbonization steps. Results from Raman spectroscopy indicate higher graphitic structure for PCFA carbon as compared to the Kraft lignin, as seen from G/D ratios of 1.92 vs 1.15 which was supported by a high percentage of graphitic (C-C) bond observed from X-ray photoelectron spectroscopy (XPS). Moreover, from the XRD and TEM a larger crystal size (Lc=12.2 nm) for the PCFA fiber was obtained which correlates to the higher modulus and conductivity of the fiber. These plant-sourced carbon fabrics have a valuable impact on zero carbon footprint materials. In order to improve the strength and flexibility of the non-woven carbon fabric, lignin was blended with the synthetic polymer Poly acrylonitrile (PAN) in different concertation, resulting in electrical conductivity up to (7.7 S/cm) on blend composition which is enough for sensing and EMI shielding applications. Next, the design of experiments approach was used to identify the contribution of the carbonization parameters on the conductivity of the fabrics and architecture of the fibers, results show carbonization temperature as the major contributing factor to the conductivity of non-woven fabric. Finally, a manufacturing procedure was develop inspired by the ...
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Date: August 2017
Creator: Rizvi, Syed Hussain Raza
Partner: UNT Libraries

Understanding the Nature and Reactivity of Residual Lignin for Improved Pulping and Bleaching Efficiency

Description: One of the most formidable challenges in kraft pulping to produce bleached chemical pulps is how to effectively remove the last 5-10% of lignin while maintaining the fiber quality. To avoid a severe fiber degradation, kraft pulping is usually terminated in the 25-30 kappa number range and then followed by an elementally chlorine free (ECF) or a totally chlorine free (TCF) bleaching sequence to reduce the environmental impacts.
Date: November 30, 2001
Creator: Lai, Yuan-Zong
Partner: UNT Libraries Government Documents Department

Countercurrent Process for Lignin Separation from Biomass Matrix

Description: The overall goal of the project was to test the concept of using a twin-screw extruder to conduct autohydrolysis pretreatment of wheat straw in countercurrent fashion, demonstrate in situ solid/liquid separation, and produce a low-lignin cellulose product using ethanol as an extractant. The resultant solid product is suitable for sugar production through enzymatic hydrolysis and for pulp applications. Pilot-scale equipment was used to successfully demonstrate the process both for sugar and pulp applications.
Date: March 31, 2006
Creator: Kadam, Kiran & Lehrburger, Ed
Partner: UNT Libraries Government Documents Department

Extracellular oxidative metabolism of wood decay fungi

Description: Substantial progress has been made toward understanding the fundamental physiology and genetics of wood decay fungi, microbes that are capable of degrading all major components of plant cell walls. Efficient utilization of lignocellulosic biomass has been hampered in part by limitations in our understanding of enzymatic mechanisms of plant cell wall degradation. This is particularly true of woody substrates where accessibility and high lignin content substantially complicate enzymatic 'deconstruction'. The interdisciplinary research has illuminated enzymatic mechanisms essential for the conversion of lignocellulosics to simple carbohydrates and other small molecular weight products. Progress was in large part dependent on substantial collaborations with the Department of Energy's Joint Genome Institute (JGI) in Walnut Creek and Los Alamos, as well as the Catholic University, Santiago, Chile, the Royal Institute of Technology, Stockholm, the University of Minnesota, St. Paul, and colleagues at the University of Wisconsin and the Forest Products Laboratory. Early accomplishments focused on the development of experimental tools (2, 7, 22, 24-26, 32) and characterization of individual genes and enzymes (1, 3-5, 8, 9, 11, 14, 15, 17, 18, 23, 27, 33). In 2004, the genome of the most intensively studied lignin-degrading fungus, Phanerochaete chrysosporium, was published (21). This milestone lead to additional progress on this important model system (6, 10, 12, 13, 16, 28-31) and was further complemented by genome analysis of other important cellulose-degrading fungi (19, 20). These accomplishments have been highly cited and have paved the way for whole new research areas.
Date: April 21, 2010
Creator: Cullen, Daniel
Partner: UNT Libraries Government Documents Department

A deep transcriptomic analysis of pod development in the vanilla orchid (Vanilla planifolia)

Description: This research article describes very large gene sequence datasets from vanilla pods at different times of development, representing different tissue types, including the seeds, hairs, and placental and mesocarp tissues within the pod.
Date: November 7, 2014
Creator: Rao, Xiaolan; Krom, Nick; Tang, Yuhong; Widiez, Thomas; Havkin-Frenkel, Daphna; Belanger, Faith C. et al.
Partner: UNT College of Arts and Sciences

Computational inference of the structure and regulation of the lignin pathway in Panicum virgatum

Description: This article uses a systems biological modeling approach to address the challenge of in vivo measurements to elucidate the structure and regulation of the lignin pathway through a computational characterization of alternate candidate topologies.
Date: September 17, 2015
Creator: Faraji, Mojdeh; Fonseca, Luis L.; Escamilla-Treviño, Luis; Dixon, R. A. & Voit, Eberhard O.
Partner: UNT College of Arts and Sciences

Loss of function of folylpolyglutamate synthetase 1 reduces lignin content and improves cell wall digestibility in Arabidopsis

Description: This article observes genetic and biochemical support for the importance of folylpolyglutamates in the lignocellulosic pathway and reinforces previous observations that targeting a single FPGS isoform for down-regulation leads to reduced lignin in plants.
Date: December 21, 2015
Creator: Srivastava, Avinash C.; Chen, Fang; Ray, Tui; Pattahil, Sivakumar; Peña, Maria J.; Avci, Utku et al.
Partner: UNT College of Arts and Sciences

Supplementary materials: Improving saccharification efficiency of alfalfa stems through modification of the terminal stages of monolignol biosynthesis

Description: Supplementary materials accompanying an article on improving saccharification efficiency of alfalfa stems through modification of the terminal stages of monolignol biosynthesis.
Date: September 27, 2008
Creator: Jackson, Lisa A.; Shadle, Gail L.; Zhou, Rui; Nakashima, Jin; Chen, Fang & Dixon, R. A.
Partner: UNT College of Arts and Sciences

A new method for isolating large quantities of Arabidopsis trichomes for transcriptome, cell wall and other types of analyses

Description: Article on a new method for isolating large quantities of Arabidopsis trichomes for transcriptome, cell wall and other types of analyses.
Date: November 2008
Creator: Marks, M. David; Betancur, Lissete; Gilding, Edward; Chen, Fang; Bauer, Stefan; Wenger, Jonathan P. et al.
Partner: UNT College of Arts and Sciences

Improved forage digestibility of tall fescue (Festuca arundinacea) by transgenic down-regulation of cinnamyl alcohol dehydrogenase

Description: Article on improved forage digestibility of tall fescue (Festuca arundinacea) by transgenic down-regulation of cinnamyl alcohol dehydrogenase.
Date: September 19, 2003
Creator: Chen, Lei; Auh, Chung-Kyoon; Dowling, Paul; Bell, Jeremy; Chen, Fang; Hopkins, Andrew et al.
Partner: UNT College of Arts and Sciences

Batch Microreactor Studies of Base Catalyzed Ligin Depolymerization in Alcohol Solvents

Description: The depolymerization of organosolv-derived lignins by bases in methanol or ethanol solvent was studied in rapidly heated batch microreactors. The conversion of lignin to ether solubles by KOH in methanol or ethanol was rapid at 290 "C, reaching the maximum value within 10-15 minutes. An excess of base relative to Lignin monomer units was required for maximum conversion. Strong bases (KOH, NaOH, CSOH) convert more of the lignin to ether soluble material than do weaker bases LiOH, Ca(OH)2, and NacCO2). Ethanol and methanol are converted to acetic and formic acid respectively under the reaction conditions with an activation energy of approximately 50 kcal/mol. This results in a loss of solvent, but more importantly neutralizes the base catalyst, halting forward progress of the reaction.
Date: February 3, 1999
Creator: Evans, L.; Littlewolf, A.; Lopez, M. & Miller, J.E.
Partner: UNT Libraries Government Documents Department

Mechanisms of Lignin Biosynthesis During Xylogenesis in Zinnia elegans. Final report

Description: The original plan for this project was to use Zinnia elegans and its xylogenic cell differentiation system to dissect the role(s) played in lignin deposition by the three classes of laccases (p-diphenoloxidases) the authors had previously detected in zinnia stem extracts. The project, was broadly divided into two general areas--biochemistry/enzymology and molecular biology/genetic engineering--each of which was pursued by one of two graduate students. As noted in the attached publication list, DOE funding for this project facilitated the publication of five (5) research papers, and two (2) more papers slated for peer-review publication are currently nearing completion. In addition, our research results were presented at nine(9) national and international scientific meetings over the past four years. Some of the major findings reported in theses papers and presentations are summarized.
Date: June 30, 1999
Creator: Eriksson, Karl-Erik L. & Dean, Jeffrey F.D.
Partner: UNT Libraries Government Documents Department

Changes in Cell Wall Carbohydrate Extractability are Correlated with Reduced Recalcitrance of HCT Downregulated Alfalfa Biomass

Description: Article on changes in cell wall carbohydrate extractability and how these are correlated with reduced recalcitrance of hydroxycinnamoyl transferase (HCT) downregulated alfalfa biomass.
Date: August 2012
Creator: Pattathil, Sivakumar; Saffold, Trina; Gallego-Giraldo, Lina; O'Neill, Malcolm; York, William S.; Dixon, R. A. et al.
Partner: UNT College of Arts and Sciences

Mutation of WRKY transcription factors initiates pith secondary wall formation and increases stem biomass in dicotyledonous plants

Description: Article discussing how the mutation of WRKY transcription factors initiates pith secondary wall formation and increases stem biomass in dicotyledonous plants.
Date: December 21, 2010
Creator: Wang, Huan-Zhong; Avci, Utku; Nakashima, Jin; Hahn, Michael G.; Chen, Fang & Dixon, R. A.
Partner: UNT College of Arts and Sciences