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Title: Catalyst-free carbon nanotubes from coal-based material

Abstract

DC-Arc Discharge technique has been used to synthesize carbon nanotubes from super clean coal samples instead of graphite electrodes filled with metal catalysts. The adverse effect of the mineral matter present in coal may be, thus, avoided. The cathode deposits showed the presence of single walled carbon nanotubes as well, which are generally known to be formed only in presence of transition metal catalysts and lanthanides. The process also avoids the tedious purification treatments of carbon nanotubes by strong acids to get rid of metal catalysts produced as impurities along with nanotubes. Thus, coal may be refined and demineralized by an organorefining technique to obtain super clean coal, an ultra low ash coal which may be used for the production of carbon nanotubes. The residual coal obtained after the organorefining may be used as an energy source for raising steam for power generation. Thus, coal may afford its use as an inexpensive feedstock for the production of carbon nanotubes besides its conventional role as a fuel for power generation.

Authors:
; ;  [1]
  1. Indian Institute of Technology, New Delhi (India)
Publication Date:
OSTI Identifier:
20838224
Resource Type:
Journal Article
Resource Relation:
Journal Name: Energy Sources, Part A: Recovery, Utilization, and Environmental Effects; Journal Volume: 29; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
01 COAL, LIGNITE, AND PEAT; COAL; DEMINERALIZATION; ELECTRIC DISCHARGES; FULLERENES; NANOSTRUCTURES; ELECTRIC ARCS; CARBON; CATHODES

Citation Formats

Mathur, R.B., Lal, C., and Sharma, D.K. Catalyst-free carbon nanotubes from coal-based material. United States: N. p., 2007. Web. doi:10.1080/009083190910334.
Mathur, R.B., Lal, C., & Sharma, D.K. Catalyst-free carbon nanotubes from coal-based material. United States. doi:10.1080/009083190910334.
Mathur, R.B., Lal, C., and Sharma, D.K. Mon . "Catalyst-free carbon nanotubes from coal-based material". United States. doi:10.1080/009083190910334.
@article{osti_20838224,
title = {Catalyst-free carbon nanotubes from coal-based material},
author = {Mathur, R.B. and Lal, C. and Sharma, D.K.},
abstractNote = {DC-Arc Discharge technique has been used to synthesize carbon nanotubes from super clean coal samples instead of graphite electrodes filled with metal catalysts. The adverse effect of the mineral matter present in coal may be, thus, avoided. The cathode deposits showed the presence of single walled carbon nanotubes as well, which are generally known to be formed only in presence of transition metal catalysts and lanthanides. The process also avoids the tedious purification treatments of carbon nanotubes by strong acids to get rid of metal catalysts produced as impurities along with nanotubes. Thus, coal may be refined and demineralized by an organorefining technique to obtain super clean coal, an ultra low ash coal which may be used for the production of carbon nanotubes. The residual coal obtained after the organorefining may be used as an energy source for raising steam for power generation. Thus, coal may afford its use as an inexpensive feedstock for the production of carbon nanotubes besides its conventional role as a fuel for power generation.},
doi = {10.1080/009083190910334},
journal = {Energy Sources, Part A: Recovery, Utilization, and Environmental Effects},
number = 1,
volume = 29,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • DC-Arc technique has been used to synthesize carbon nanotubes from super clean coal, chemically cleaned coal, original coal and waste plastics instead of using high purity graphite in the presence of metal catalysts. The results obtained are compared in terms of yield, purity and type of carbon nanotubes produced from different types of raw material used. In the present study different types of raw materials have been prepared i.e. chemically cleaned coal and super clean coal, and the carbon nanotubes have been synthesized by DC Arc discharge method. Taking in account the present need of utilizing coal as a cheapermore » raw material for bulk production of carbon nanotubes and utilization of waste plastics (which itself is a potential environmental threat) for production of such an advance material the present work was undertaken. Since the process does not involve presence of any kind of metal catalyst, it avoids the cost intensive process of removal of these metal particles. The residual coal obtained after refining has major fuel potential and can be utilized for various purposes.« less
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