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

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University of Pretoria

1. Papole, Gedion John. Characterization of medium temperature gasifier pitch.

Degree: Chemistry, 2012, University of Pretoria

Pitches are important precursors for carbon materials. They are usually obtained by thermal treatment of petroleum and coal fractions. Pitches have higher carbon content and are capable of developing into graphitisable carbons upon heat treatment. Petroleum pitches are generally less aromatic than coal tar pitches. Medium-temperature gasifier pitch (MTP), from Sasol’s Lurgi process, is a potential precursor for graphitisable carbon. MTP showed a high degree of solubility in several organic solvents, namely dimethylformamide, quinoline, tetrahydrofuran, pyridine, morpholine, benzene, toluene, xylene and acetone. It was virtually insoluble in n-hexane, cyclohexane, cyclohexanol, acetonitrile and formamide. MTP pitch was partially soluble in methanol and had a solubility limit of 40 g/l at ambient temperature. MTP samples were spiked with boron to make 1000 ppm B-containing samples. The boron distribution coefficient was defined as the ratio of the boron contents of the insoluble pitch residue to the methanol-soluble pitch extracts, using a mass balance. This justified the decision to define the apparent boron partition coefficients based on the boron content of the recovered pitch residues. 4-(dibenzofuranyl) boronic acid (DBA), 2 phenoxyphenyl boronic acid (PBA), p-tolylboronic acid (TBA) and phenylboronic acid (PLA) were retained the most in the residues after methanol extraction. Over 500 ppm of PBA, TBA and PLA were retained in the pitch residues following methanol extraction. The results showed that methanol extracted substituted boron acid model compounds. Methanol dissolved mostly low molecular mass/aliphatic species, which are not important for graphitisation. The thermomechanical analysis (TMA) results showed that MTP has a low softening point compared with the methanol-insoluble (MI) fractions. The attenuated total reflectance (ATR) results showed that the benzene-insoluble (BI), toluene-insoluble (TI) and MI fractions had more intense aromatic C–H stretching peaks than their corresponding soluble fractions. Elemental analysis and the solid-state 13C nuclear magnetic resonance (NMR) results revealed that the benzene-, toluene- and methanol-insoluble fractions are more aromatic than their corresponding soluble fractions. The order of the aromaticity index for the insoluble fractions was as follows: MTP<MI<TI<BI. Matrix-assisted laser desorption (MALDI) analysis of the mass distribution revealed that the majority of compounds in MTP and its soluble and insoluble fractions were in the low molecular mass range, i.e. 190–388 atomic mass units. The thermal analysis results showed that the benzene-, toluene- and methanol-insoluble fractions were thermally stable and had higher carbon yields than their corresponding soluble fractions. MTP was thermally more stable than the methanol-, toluene- and benzene-soluble fractions. Evaluation of the polycyclic aromatic hydrocarbons (PAHs) by gas chromatography-mass spectrometry (GC-MS) showed that the methanol-insoluble fractions had lower PAH contents than MTP and MI.  … Advisors/Committee Members: Prof W Focke (advisor).

Subjects/Keywords: Pitches; Gasifier pitch; Petroleum pitches; Coal tar pitches; UCTD

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

APA (6th Edition):

Papole, G. J. (2012). Characterization of medium temperature gasifier pitch. (Masters Thesis). University of Pretoria. Retrieved from http://hdl.handle.net/2263/29488

Chicago Manual of Style (16th Edition):

Papole, Gedion John. “Characterization of medium temperature gasifier pitch.” 2012. Masters Thesis, University of Pretoria. Accessed November 15, 2019. http://hdl.handle.net/2263/29488.

MLA Handbook (7th Edition):

Papole, Gedion John. “Characterization of medium temperature gasifier pitch.” 2012. Web. 15 Nov 2019.

Vancouver:

Papole GJ. Characterization of medium temperature gasifier pitch. [Internet] [Masters thesis]. University of Pretoria; 2012. [cited 2019 Nov 15]. Available from: http://hdl.handle.net/2263/29488.

Council of Science Editors:

Papole GJ. Characterization of medium temperature gasifier pitch. [Masters Thesis]. University of Pretoria; 2012. Available from: http://hdl.handle.net/2263/29488


University of Pretoria

2. Papole, Gedion John. Characterization of medium temperature gasifier pitch .

Degree: 2012, University of Pretoria

Pitches are important precursors for carbon materials. They are usually obtained by thermal treatment of petroleum and coal fractions. Pitches have higher carbon content and are capable of developing into graphitisable carbons upon heat treatment. Petroleum pitches are generally less aromatic than coal tar pitches. Medium-temperature gasifier pitch (MTP), from Sasol’s Lurgi process, is a potential precursor for graphitisable carbon. MTP showed a high degree of solubility in several organic solvents, namely dimethylformamide, quinoline, tetrahydrofuran, pyridine, morpholine, benzene, toluene, xylene and acetone. It was virtually insoluble in n-hexane, cyclohexane, cyclohexanol, acetonitrile and formamide. MTP pitch was partially soluble in methanol and had a solubility limit of 40 g/l at ambient temperature. MTP samples were spiked with boron to make 1000 ppm B-containing samples. The boron distribution coefficient was defined as the ratio of the boron contents of the insoluble pitch residue to the methanol-soluble pitch extracts, using a mass balance. This justified the decision to define the apparent boron partition coefficients based on the boron content of the recovered pitch residues. 4-(dibenzofuranyl) boronic acid (DBA), 2 phenoxyphenyl boronic acid (PBA), p-tolylboronic acid (TBA) and phenylboronic acid (PLA) were retained the most in the residues after methanol extraction. Over 500 ppm of PBA, TBA and PLA were retained in the pitch residues following methanol extraction. The results showed that methanol extracted substituted boron acid model compounds. Methanol dissolved mostly low molecular mass/aliphatic species, which are not important for graphitisation. The thermomechanical analysis (TMA) results showed that MTP has a low softening point compared with the methanol-insoluble (MI) fractions. The attenuated total reflectance (ATR) results showed that the benzene-insoluble (BI), toluene-insoluble (TI) and MI fractions had more intense aromatic C–H stretching peaks than their corresponding soluble fractions. Elemental analysis and the solid-state 13C nuclear magnetic resonance (NMR) results revealed that the benzene-, toluene- and methanol-insoluble fractions are more aromatic than their corresponding soluble fractions. The order of the aromaticity index for the insoluble fractions was as follows: MTP<MI<TI<BI. Matrix-assisted laser desorption (MALDI) analysis of the mass distribution revealed that the majority of compounds in MTP and its soluble and insoluble fractions were in the low molecular mass range, i.e. 190–388 atomic mass units. The thermal analysis results showed that the benzene-, toluene- and methanol-insoluble fractions were thermally stable and had higher carbon yields than their corresponding soluble fractions. MTP was thermally more stable than the methanol-, toluene- and benzene-soluble fractions. Evaluation of the polycyclic aromatic hydrocarbons (PAHs) by gas chromatography-mass spectrometry (GC-MS) showed that the methanol-insoluble fractions had lower PAH contents than MTP and MI.  … Advisors/Committee Members: Prof W Focke (advisor).

Subjects/Keywords: Pitches; Gasifier pitch; Petroleum pitches; Coal tar pitches; UCTD

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

APA (6th Edition):

Papole, G. J. (2012). Characterization of medium temperature gasifier pitch . (Masters Thesis). University of Pretoria. Retrieved from http://upetd.up.ac.za/thesis/available/etd-11152012-182640/

Chicago Manual of Style (16th Edition):

Papole, Gedion John. “Characterization of medium temperature gasifier pitch .” 2012. Masters Thesis, University of Pretoria. Accessed November 15, 2019. http://upetd.up.ac.za/thesis/available/etd-11152012-182640/.

MLA Handbook (7th Edition):

Papole, Gedion John. “Characterization of medium temperature gasifier pitch .” 2012. Web. 15 Nov 2019.

Vancouver:

Papole GJ. Characterization of medium temperature gasifier pitch . [Internet] [Masters thesis]. University of Pretoria; 2012. [cited 2019 Nov 15]. Available from: http://upetd.up.ac.za/thesis/available/etd-11152012-182640/.

Council of Science Editors:

Papole GJ. Characterization of medium temperature gasifier pitch . [Masters Thesis]. University of Pretoria; 2012. Available from: http://upetd.up.ac.za/thesis/available/etd-11152012-182640/


Sardar Patel University

3. Parmar, Nileshkumar Prabhatsinh. Development and characterization of pitch based carbon fiber; -.

Degree: Materials Science, 2010, Sardar Patel University

none newline

Reference given in the end.

Advisors/Committee Members: Manocha, L M.

Subjects/Keywords: Chemical Modification of Petroleum Pitch; Element Carbon and Various Forms; Mesophase Pitch Based Carbon Fibers; pitch based carbon fiber; Pitches as Carbonaceous Precursor

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

APA (6th Edition):

Parmar, N. P. (2010). Development and characterization of pitch based carbon fiber; -. (Thesis). Sardar Patel University. Retrieved from http://shodhganga.inflibnet.ac.in/handle/10603/37185

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):

Parmar, Nileshkumar Prabhatsinh. “Development and characterization of pitch based carbon fiber; -.” 2010. Thesis, Sardar Patel University. Accessed November 15, 2019. http://shodhganga.inflibnet.ac.in/handle/10603/37185.

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

MLA Handbook (7th Edition):

Parmar, Nileshkumar Prabhatsinh. “Development and characterization of pitch based carbon fiber; -.” 2010. Web. 15 Nov 2019.

Vancouver:

Parmar NP. Development and characterization of pitch based carbon fiber; -. [Internet] [Thesis]. Sardar Patel University; 2010. [cited 2019 Nov 15]. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/37185.

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

Council of Science Editors:

Parmar NP. Development and characterization of pitch based carbon fiber; -. [Thesis]. Sardar Patel University; 2010. Available from: http://shodhganga.inflibnet.ac.in/handle/10603/37185

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

.