Research into Carbon Nanotubes and their applications is fast becoming an extremely popular topic, and any means to greatly improve the synthesis process has a huge marketability. While investigating the feasibility of continuous production of single-walled carbon nanotubes in a vertical Swirled Fluid Chemical Vapour Deposition (CVD) reactor, it was discovered that helical nanotubes were lifted from the reactor by the gas current while straight tubes remained behind. Investigation into the merits provided by the helical structure illustrated the greatly increased likeliness for helical tubes to be lifted from the reactor by the carrier gas giving rise to positive speculation of their possible use in vertical CVD reactors in the future. 1. Introduction CNTs are allotropes of carbon with a nanostructure that can have a length-to-diameter ratio as large as 28,000,000？:？1, which is unequalled by any other material [1]. The small dimensions, strength, and the remarkable physical properties of these structures allow for a very unique material with a whole range of promising applications [2]. The discovery of single-walled carbon nanotubes (SWCNTs) proved to be an extremely important development since the structures appeared to be approximate to those of the “ideal” nanotubes [3] consisting of tubes with walls only one atom thick. To use Paradise and Goswami’s [4] description: “Ideal Nanotubes can be described as a seamless cylinder of rolled up hexagonal networks of carbon atoms.” They also describe possible applications ranging from semiconductors, electronic memory, drive products, and medical delivery systems to uses in plastics such as automobile body panels, paint, tires, and as flame retardants in polyethylene and polypropylene. As SWCNTs are of such importance, there is much marketability for any means by which to improve their synthesis. The best means by which to do this is by developing a fully continuous process. While this process could provide a means to produce larger quantities of SWCNTs, separation and purification is still expensive and so any advantage that results in a purer sample is very desirable. In a vertical reactor, very little is known about the factors that affect which nanotubes will be lifted from the reactor which gives rise to the possibility that given more knowledge, control of certain factors such as shape may provide the means to produce purer products. 2. Process Overview SWCNTs are a very important variety of carbon nanotube because they possess important electronic properties that the multiwalled carbon nanotube (MWCNT)
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