About Us
NanotubesSWCNT Technology
Nano-C's process technology offers the following advantages:
An exothermic production process. Nano-C's process uses premixed combustion of gas after introduction of catalyst precursors with a cold gas mixture.
Selective production of SWCNT. Nano-C has consistently demonstrated that the control of its process leads to exclusive and selective production of SWCNTs.
Continuous operations. Product can be manufactured and collected on a continuous basis. Product collection techniques at our disposal include conventional bag-house filtration and continuous collection in liquids with no atmospheric exposure.
Sustainable operations. As the manufacturing is done under sub-atmospheric pressure, potential for exposure is inherently limited by design.
Purification. Existing purification techniques for removing metallic catalyst particles can be used, whether batch or continuous.
Scale and scalability. Our nanotube operation ran at 1.0-1.5 g/day in Q1 ‘05. In Q2 '06, a larger burner was installed which reached 10 - 15 g/8-hour day. Production rates as of Q3 ‘09 reached 5 grams per hour of as-produced material. The resulting equipment is sufficiently large to demonstrate the scalability of the technology and to provide samples to interested partners and customers.
Reproducibility. Reproducibility of the nanotube-production process is ensured by rigorous control of all process parameters whether operated as a continuous operation or batch. Quality control is conducted by Raman spectroscopy which allows for the assessment of the diameter of SWCNT and of the relative abundance of the D-band indicating the level of impurities or other symmetry-breaking effects. While most measurements have been done at 785 nm, similar results have been obtained at 647, 633 and 514 nm. Product analysis of multiple runs at nearly identical conditions has revealed very similar Raman spectra in all cases. All spectra showed a narrow distribution of the radial-breathing mode (RBM) with pronounced peaks between 190 and 280 cm-1 which corresponds to tube diameters of ranging from 0.9 to 1.3 nm. The D-band, appearing near a wave number of 1350 cm-1, was very weak in all cases with typical ratios between the RBM and D-bands of > 15. Nano-C’s process technology is destined to run on a continuous basis, much like carbon black plants are run today. This will virtually eliminate the notion of batch-to-batch variability.
Multiple degrees of freedom in operating conditions. Current control points include the following conditions of operation: pressure, type & particle size of catalyst, fuel-oxygen ratio, dilution with inert gas, cold gas velocity.
Process extensions. Among the possibilities are: the use of electric fields between the burner surface (nanotube generation) and the collector to potentially achieve greater alignment of carbon nanotubes; in situ processing of substrates; and liquid phase collection among others.