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Title: Flame Synthesis of Carbon Nanotubes Using Low Calorific Value Gases

Abstract

Nanostructures formed in diffusion flames of pure fuels [CH{sub 4}, C{sub 3}H{sub 8}, and C{sub 2}H{sub 2}] at different fuel flow rates have been analyzed. Synthesis samples have been also collected from diffusion flames of various fuel blends [H{sub 2}-CH{sub 4}, H{sub 2}-CO, H{sub 2}-C{sub 3}H{sub 8}, H{sub 2}-C{sub 2}H{sub 2}] at different combustion conditions. SEM images of particulate samples collected from H{sub 2}-CH{sub 4} diffusion flames show formation of nanostructures. However, the formation of nanostructures only occurs at a narrow window of fuel compositions (< 10% H{sub 2} concentration in the mixture) and flow conditions (Jet Exit Reynolds number Re{sub j} = 200). At higher H{sub 2} concentration and flow velocity, formation of nanostructures diminishes and H{sub 2}-CH{sub 4} flames produce amorphous carbon and soot particles.

Authors:
; ;
Publication Date:
Research Org.:
University Of Texas At El Paso
Sponsoring Org.:
USDOE
OSTI Identifier:
924881
DOE Contract Number:
FG26-06NT42749
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
03 NATURAL GAS; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CARBON; NANOSTRUCTURES; FLAMES; METHANE; PROPANE; ACETYLENE; SYNTHESIS; HYDROGEN; CONCENTRATION RATIO; COMBUSTION KINETICS

Citation Formats

Jorge Camacho, Mahesh Subramanya, and Ahsan R. Choudhuri. Flame Synthesis of Carbon Nanotubes Using Low Calorific Value Gases. United States: N. p., 2007. Web. doi:10.2172/924881.
Jorge Camacho, Mahesh Subramanya, & Ahsan R. Choudhuri. Flame Synthesis of Carbon Nanotubes Using Low Calorific Value Gases. United States. doi:10.2172/924881.
Jorge Camacho, Mahesh Subramanya, and Ahsan R. Choudhuri. Sat . "Flame Synthesis of Carbon Nanotubes Using Low Calorific Value Gases". United States. doi:10.2172/924881. https://www.osti.gov/servlets/purl/924881.
@article{osti_924881,
title = {Flame Synthesis of Carbon Nanotubes Using Low Calorific Value Gases},
author = {Jorge Camacho and Mahesh Subramanya and Ahsan R. Choudhuri},
abstractNote = {Nanostructures formed in diffusion flames of pure fuels [CH{sub 4}, C{sub 3}H{sub 8}, and C{sub 2}H{sub 2}] at different fuel flow rates have been analyzed. Synthesis samples have been also collected from diffusion flames of various fuel blends [H{sub 2}-CH{sub 4}, H{sub 2}-CO, H{sub 2}-C{sub 3}H{sub 8}, H{sub 2}-C{sub 2}H{sub 2}] at different combustion conditions. SEM images of particulate samples collected from H{sub 2}-CH{sub 4} diffusion flames show formation of nanostructures. However, the formation of nanostructures only occurs at a narrow window of fuel compositions (< 10% H{sub 2} concentration in the mixture) and flow conditions (Jet Exit Reynolds number Re{sub j} = 200). At higher H{sub 2} concentration and flow velocity, formation of nanostructures diminishes and H{sub 2}-CH{sub 4} flames produce amorphous carbon and soot particles.},
doi = {10.2172/924881},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Mar 31 00:00:00 EDT 2007},
month = {Sat Mar 31 00:00:00 EDT 2007}
}

Technical Report:

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