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You searched for subject:(Organosolv Fractionation). Showing records 1 – 3 of 3 total matches.

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University of Tennessee – Knoxville

1. Astner, Anton Friedrich. Lignin Yield Maximization of Lignocellulosic Biomass by Taguchi Robust Product Design using Organosolv Fractionation.

Degree: MS, Forestry, 2012, University of Tennessee – Knoxville

Lignin, a byproduct of the organosolv pretreatment process using lignocellulosic biomass from switchgrass (Panicum virgatum) and tulip poplar (Liriodendron tulipifera) is currently being explored for its potential use in the production of value-added chemicals and biobased polymers. Pretreatment is one of the most expensive processing steps in cellulosic biomass conversion. Optimization of the process is one of the major goals of the biomass-toethanol conversion process. Taguchi Robust Product Design (TRPD) provides an effective engineering experimental design method for optimizing a system and designing products that are robust to process variations. Given the results of several preliminary studies of the organosolv pretreatment process, four controllable design factors (inner array) were used in the TRPD: process temperature (120°C, 140°C, 160°C), fractionation time (56 minutes, 90 minutes), sulfuric acid concentration (0.025 M, 0.05 M, 0.1 M), and feedstock ratio (switchgrass/tulip poplar ratios of 10%/90%, 50%/50%, 90%/10%, based on both mass and volume of feedstock). Process noise was induced in the experiment by using either the mass-based or volume-based feedstock charges of switchgrass and tulip poplar. A maximum mean lignin yield of 78.63 wt% was found in the study. Optimum conditions for maximum lignin yield were found at a 90 minute runtime, 160°C process temperature, 0.1 M sulfuric acid concentration, and a feedstock composition of 90% switchgrass and 10% tulip poplar. The most statistically significant factor influencing lignin yield was process temperature. There was statistical evidence that lignin yield increased after 120°C for both feedstock charges of switchgrass and tulip poplar (p-value < 0.0001 for massbased, p-value < 0.0001 for volume-based). The variance in lignin yield declined as the proportion of switchgrass increased (p-value = 0.0346 for mass-based and p-value = 0.0678 for volume-based). The finding of a local maximum for lignin yield for process temperature at 160°C suggests that high processing temperatures are required to receive high lignin yields. The finding that the variance in lignin yield declined as the switchgrass percentage of feedstock increased may provide a pathway for other researchers interested in maximizing switchgrass use in the pretreatment process. Advisors/Committee Members: Joseph J. Bozell, Timothy M. Young, David P. Harper.

Subjects/Keywords: Lignin yield; Organosolv Fractionation; Taguchi Robust Product Design; Process Optimization; Catalysis and Reaction Engineering; Other Materials Science and Engineering; Process Control and Systems

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Astner, A. F. (2012). Lignin Yield Maximization of Lignocellulosic Biomass by Taguchi Robust Product Design using Organosolv Fractionation. (Thesis). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_gradthes/1359

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Astner, Anton Friedrich. “Lignin Yield Maximization of Lignocellulosic Biomass by Taguchi Robust Product Design using Organosolv Fractionation.” 2012. Thesis, University of Tennessee – Knoxville. Accessed January 24, 2020. https://trace.tennessee.edu/utk_gradthes/1359.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Astner, Anton Friedrich. “Lignin Yield Maximization of Lignocellulosic Biomass by Taguchi Robust Product Design using Organosolv Fractionation.” 2012. Web. 24 Jan 2020.

Vancouver:

Astner AF. Lignin Yield Maximization of Lignocellulosic Biomass by Taguchi Robust Product Design using Organosolv Fractionation. [Internet] [Thesis]. University of Tennessee – Knoxville; 2012. [cited 2020 Jan 24]. Available from: https://trace.tennessee.edu/utk_gradthes/1359.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Astner AF. Lignin Yield Maximization of Lignocellulosic Biomass by Taguchi Robust Product Design using Organosolv Fractionation. [Thesis]. University of Tennessee – Knoxville; 2012. Available from: https://trace.tennessee.edu/utk_gradthes/1359

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


University of Western Ontario

2. Shui, Tao. Fractionation of cornstalk into cellulose and lignin for the production of sodium carboxymethyl cellulose.

Degree: 2016, University of Western Ontario

This thesis project aimed to fractionate cornstalk into cellulose and lignin, and utilize the crude cornstalk-derived cellulose for the production of sodium carboxymethyl cellulose and the lignin for the sybthesis of bio-based phenol-formaldehyde resole resins as wood adhesives. In this thesis work, cornstalk was efficiently fractionated into crude cellulose and crude lignin in mixed solvents of acetic acid, formic acid and water at a solid/agent ratio of 1:5 (g/mL) at 80-100 °C for 120-240 min. The best conditions for organosolv fractionation of cornstalk among the test conditions were determined as follows: mixed solvent of acetic acid/formic acid/water (3:6:1, v/v/v), HCl as the catalyst, 90 °C and 180 min residence time, where the yield (and purity) of crude cellulose and lignin products were approximate 53% (85%) and 38% (44%), respectively, on the basis of mass of oven-dried cornstalk, and the obtained crude cellulose products have very low residual lignin contents (<4%). The crude cellulose fractionated from cornstalk was further used, after bleaching, as feedstock for the synthesis of sodium carboxymethyl cellulose (CMC). The best molar ratio of the reaction reagents (NaOH/ClCH2COOH /cellulose) among the test conditions were investigated and determined to be 4.0:2.5:1 and 4.6:2.8:1, or the molar ratio of NaOH/ClCH2COOH being 1.6-1.64. The CMC products obtained at the best reactants molar ratios have relatively high water solubility and reasonably high viscosity and molecular weights. The average degree of substitution (DS) of these two CMC products obtained at the best molar ratios among the test conditions are 0.57 and 0.85, respectively.

Subjects/Keywords: Cornstalk; organosolv fractionation; acetic acid; formic acid; crude cellulose; organoslv lignin; bleaching; etherification; sodium carboxymethyl cellulose; water solubility; degree of substitution (DS); Bioresource and Agricultural Engineering; Other Chemical Engineering; Polymer Science

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Shui, T. (2016). Fractionation of cornstalk into cellulose and lignin for the production of sodium carboxymethyl cellulose. (Thesis). University of Western Ontario. Retrieved from https://ir.lib.uwo.ca/etd/3959

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Shui, Tao. “Fractionation of cornstalk into cellulose and lignin for the production of sodium carboxymethyl cellulose.” 2016. Thesis, University of Western Ontario. Accessed January 24, 2020. https://ir.lib.uwo.ca/etd/3959.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Shui, Tao. “Fractionation of cornstalk into cellulose and lignin for the production of sodium carboxymethyl cellulose.” 2016. Web. 24 Jan 2020.

Vancouver:

Shui T. Fractionation of cornstalk into cellulose and lignin for the production of sodium carboxymethyl cellulose. [Internet] [Thesis]. University of Western Ontario; 2016. [cited 2020 Jan 24]. Available from: https://ir.lib.uwo.ca/etd/3959.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Shui T. Fractionation of cornstalk into cellulose and lignin for the production of sodium carboxymethyl cellulose. [Thesis]. University of Western Ontario; 2016. Available from: https://ir.lib.uwo.ca/etd/3959

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


University of Tennessee – Knoxville

3. Attwenger, Andreas. VALUE-ADDED LIGNIN BASED CARBON FIBER FROM ORGANOSOLV FRACTIONATION OF POPLAR AND SWITCHGRASS.

Degree: MS, Forestry, 2014, University of Tennessee – Knoxville

Carbon fiber has unique properties that include high strength, low density and excellent chemical and thermal resistance. However, they have a low level of utilization because of their high price; typically around $30/kg for an entry level polyacrylonitrile (PAN) based carbon fiber. Low-cost carbon fibers derived from lignin are currently being investigated at the University of Tennessee, because using lignin as a precursor could significantly reduce production costs. Lignin obtained from the pulp and paper and the emerging biofuel industries have the potential to be used for carbon fiber production, however, they are typically unsuitable because of the high levels of impurity and variable thermal properties. We are therefore examining the potential of a novel organosolv process to provide high purity lignin for carbon fiber production. This fractionation separates woody and herbaceous bioenergy crops into their three main components: cellulose, hemicellulose, and lignin, each of which can be used within the biorefinery for the production of fuels or chemicals. In this program, organosolv derived lignin from both tulip poplar (Liriodendron tulipifera) and Alamo switchgrass (Panicum virgatum) were recovered and compared as starting materials for carbon fiber. The organosolv derived lignin and commercially derived lignin were analyzed using several different methods to assess quality differences for potential carbon fiber manufacture. Their purities, chemical structures, consistencies, thermal, and carbonization properties were evaluated and lignin exhibiting optimal properties was used for fiber spinning and conversion to carbon fiber. Lignin of best thermal performances were achieved in isolation at 150°C to 170°C with an acid concentration of 0.05 and 0.1 M H2SO4, and a fractionation time of 120 minutes. Organosolv fractionation conditions and their influence on the properties of lignin based carbon fiber are presented in this thesis. Advisors/Committee Members: Joseph J. Bozell, Timothy M. Young, Alexander Petutschnigg, David P. Harper.

Subjects/Keywords: Organosolv fractionation; lignin analysis; carbon fiber; melt-spinning; lignin based carbon fiber; biopolymers and renewable polymers; Agricultural Economics; Biochemistry; Biotechnology; Forest Biology; Other Forestry and Forest Sciences; Wood Science and Pulp, Paper Technology

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Attwenger, A. (2014). VALUE-ADDED LIGNIN BASED CARBON FIBER FROM ORGANOSOLV FRACTIONATION OF POPLAR AND SWITCHGRASS. (Thesis). University of Tennessee – Knoxville. Retrieved from https://trace.tennessee.edu/utk_gradthes/2768

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Attwenger, Andreas. “VALUE-ADDED LIGNIN BASED CARBON FIBER FROM ORGANOSOLV FRACTIONATION OF POPLAR AND SWITCHGRASS.” 2014. Thesis, University of Tennessee – Knoxville. Accessed January 24, 2020. https://trace.tennessee.edu/utk_gradthes/2768.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Attwenger, Andreas. “VALUE-ADDED LIGNIN BASED CARBON FIBER FROM ORGANOSOLV FRACTIONATION OF POPLAR AND SWITCHGRASS.” 2014. Web. 24 Jan 2020.

Vancouver:

Attwenger A. VALUE-ADDED LIGNIN BASED CARBON FIBER FROM ORGANOSOLV FRACTIONATION OF POPLAR AND SWITCHGRASS. [Internet] [Thesis]. University of Tennessee – Knoxville; 2014. [cited 2020 Jan 24]. Available from: https://trace.tennessee.edu/utk_gradthes/2768.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Attwenger A. VALUE-ADDED LIGNIN BASED CARBON FIBER FROM ORGANOSOLV FRACTIONATION OF POPLAR AND SWITCHGRASS. [Thesis]. University of Tennessee – Knoxville; 2014. Available from: https://trace.tennessee.edu/utk_gradthes/2768

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.