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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Experimental investigation and systems modeling of fractional catalytic pyrolysis of pine

Goteti, Anil Chaitanya 11 November 2010 (has links)
The fractional catalytic pyrolysis of pine was studied both experimentally and through models. A preliminary stage economic analysis was conducted for a wood chip pyrolysis facility operating at a feed rate of 2000 wet ton/day for producing bio-oil. In the experimental study, multiple grams of bio oil were produced in a single run to facilitate the more extensive characterization of the oil produced from pyrolysis of biomass impregnated with different catalysts. Two reactors configurations, a screw extruder and a tubular pyrolysis reactor, were explored to perform fractional catalytic pyrolysis of biomass. The main aim of performing a wood pyrolysis reaction in a modified screw extruder is to facilitate the simultaneous collection of bio-oil produced from staged temperature pyrolysis of three main components of wood, cellulose, hemicellulose and lignin, at a reasonable scale. Apart from complete characterization of bio-oil, this will enable us to study the effect of various selected catalysts on the quality of bio-oil and the percentage of char produced, and the influence of process parameters on chemical composition of the pyrolysis oils. These experiments were later performed in a tubular pyrolysis reactor due to the difficulty of making different parts of the extruder work well together. The goal of these experiments is to produce bio-oil in multiple grams from fractional catalytic pyrolysis of wood. This will enable us to study the effect of catalyst on the chemical composition of the oil and percentage of char produced. In the modeling studies, a model of an auger reactor comprised of three different zones run at different temperatures to facilitate the collection of oil from pyrolysis of three major components of wood, namely cellulose, hemicelluloses and lignin, was developed. The effect of residence time distribution (RTD), and zone temperatures based on kinetic models on the yield of products was studied. Sensitivity of the Arrhenius rate constants calculated from synthetic data with respect to small variations in process parameters was evaluated. In the economic analysis of a wood chip pyrolysis facility, mass and energy calculations were performed based on a feed rate of 2000 wet tons/day of wood chips to the dryer. The cost of bio-oil at 10% return on investment was proposed and the sensitivity of the selling price of bio-oil with respect to capital and operating costs was analyzed. The experimental study will serve as a benchmark in exploring the above mentioned reactor configurations further. Alkali metal carbonates were used to study the quality of oil produced from pine pyrolysis. It was established that these catalysts, when added in the same molar ratio basis, increase the percentage of char. However, complete characterization of these oils for different catalysts needs to be done. Systems modeling of pyrolysis in an auger reactor established that the kinetic parameters (depending on experimental set up) and the RTD (Residence Time Distribution) parameters play a crucial role in determining the yield of oil. Variations in temperature of zone 3 play a crucial role in varying the output of oil whereas variations in temperatures of zones 2 and 1 do not significantly impact the output of oil. For a given reaction kinetic scheme for the pyrolysis reactions, calculated values of the kinetic rate constants are not sensitive to errors in experimental conditions. It was also established that the experimental error in calculation of the RTD parameters can induce error in calculation of the Arrhenius constants but these values can still predict the yield of products accurately. In the economic analysis of wood chip pyrolysis, the selling price of the bio-oil according to the cost calculation is projected to be $1.49/gal. The production cost of bio-oil is $ 1.20/gal. The cost of bio-oil is extremely sensitive to variations in operating cost (for example, cost of feed stock and selling price of char) and is not significantly affected by the variations in capital cost.
42

Design of waste tyre pyrolysis process /

Lee, King Lung. January 2009 (has links)
Includes bibliographical references (p. 136-148).
43

A study of the pyrolytic digestion of proteins by mass spectrometry

Zhang, Shaofeng. January 2008 (has links)
Thesis (Ph. D.)--University of Wyoming, 2008. / Title from PDF title page (viewed Feb. 3, 2010). Includes bibliographical references.
44

Pyrolysis studies of synthetic polymers by mass spectrometry and other methods /

Chan, Kit-ha, January 1984 (has links)
Thesis--Ph. D., University of Hong Kong, 1984.
45

The pyrolysis of methyl chlorocarbonate

Davis, Jefferson Clark, 1931- January 1954 (has links)
No description available.
46

PYGCMS investigation of the mechanism of Maillard reaction using isotopically enriched amino-acids and d-glucoses

Keyhani, Anahita. January 1997 (has links)
Pyrolysis/GC/MS was utilized as an integrated reaction, separation and identification system to study the thermal degradation products of non-volatile Maillard flavor precursors. Model systems of scL-phenylalanine (aromatic amino acid), glycine and scL-alanine (aliphatic amino acids), scL-serine ($ beta$-hydroxy amino acids) and scL-methionine (sulphur containing amino acid) were investigated. Quartz tube pyrolysis of scD-glucose/amino acid or dicarbonyl/amino acid mixtures shortened the analysis time (from hours to minutes) and eliminated the need for extraction since the volatiles generated from the precursors are directly transferred into the GC column. / Phenylalanine Amadori product and different model systems containing phenylalanine and different reducing sugars were studied. Ribbon pyrolysis was used to study the effect of temperature (150, 200, 250$ sp circ$C) on the efficiency of formation of initial pyrolysis products from phenylalanine and Amadori phenylalanine. Quartz tube pyrolysis was used at 250$ sp circ$C to enhance the secondary reactions. These studies revealed the formation of pyridine and naphthalene derivatives such as 3,5-diphenylpyridine, 1(2)-naphthaleneamine, N-methyl-1(2)-aminonaphthalene, 1-aminoanthracene, 2$ sp prime$-phenyl-pyrrolo (4,5-A) dihydronaphthalene, 1(2)-(N-phenethyl)napthaleneamine and 1(2)-(N-phenethyl-N-methyl)naphthaleneamine. / Model studies using scD- ($ sp{13}$C) glucoses and a series of dicarbonyl compounds with labeled ($ sp{15}$N/$ sp{13}$C) glycines and ($ sp{15}$N/$ sp{13}$C) alanines identified a new chemical transformation of $ alpha$-dicarbonyls, that lead to the addition of alkyl groups from the amino acid to the $ alpha$-dicarbonyl compounds, instead of the amino group as in the case of the Strecker type interaction between the two reactants. Thus, glyoxal and pyruvaldehyde can be transformed into pyruvaldehyde and 2,3-butanedione respectively, by glycine and 2-ketobutanal and 2,3-pentanedione respectively, by scL-alanine. The labeled glycine model studies indicated that methyl substituted pyrazines and pyrazinones formed in the model systems, have a common intermediate. Two pathways of pyrazinone formation were distinguished based on the labeling experiments, one involving the reaction of three moles of glycine and the other the interaction of the dipeptide glycylglycine with an $ alpha$-dicarbonyl compound. / A major product of the reaction of scD-glucose with excess glycine was detected by Py/GC/MS analysis and subsequently synthesized and isolated using focused microwave irradiation at atmospheric pressure conditions. Spectroscopic analysis by NMR, FTIR, MS and UV in conjunction with labeling studies have indicated the unknown compound to be 5-hydroxy-1,3-dimethyl-2 (1H) -quinoxalinone. The labeling studies indicated the incorporation of ten carbon atoms (six from sugar, one C-1 atom of glycine, and three C-2 atoms of glycine) and two nitrogens. / scL-Serine was found to be a unique amino acid generating in the absence of sugar a variety of heterocyclic compounds. Under pyrolytic conditions scL-serine can be viewed as a potential mixture of glycine, alanine, serine, formaldehyde and dicarbonyl compounds. / Model studies with scL-methionine provided evidence that methional (Strecker aldehyde) generated under Quartz tube pyrolysis undergoes secondary reactions with amino compounds generating 1,3-thiazines or 3-substituted pyridine in a similar fashion to that of scL-phenylalanine systems where 3-substituted pyridines were also identified. (Abstract shortened by UMI.)
47

Oxidative pyrolysis studies of synthetic polymers

Gardner, Russell Otis 12 1900 (has links)
No description available.
48

Kinetics studies of the flash pyrolysis of wood bark

Mok, Steven Lai-Kwok. January 1984 (has links)
No description available.
49

The thermal degradation of polynorbornene

Wedlake, Michael Douglas 11 1900 (has links)
No description available.
50

A numerical model of the synthesis of carbon black by benzene pyrolysis

Ivie, Jimmy John 08 1900 (has links)
No description available.

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