Carbon nanotubes (CNTs) attracted a lot of attention because of their unique structures and special properties. Since their discovery, different production methods have been introduced to synthesize CNTs. The main goal is to obtain a synthesis method which be economical, high quality productions, controllable and capacity to product carbon nanotubes in large scale. In this thesis, floating catalyst chemical vapor deposition was used because of lots of its advantages like the ability to use in industries, synthesis unmixed carbon nanotubes and control the kind of CNTs by controlling synthesis parameters. Xylene, ferrocene, thiophenethe tests, catalyst concentration, temperature and carriergas flow was selected as the main parameters and in the 1-6 wt% , 800-1200 , hydrogen concentration and flow of hydrogen ga on the quality of synthesized carbon nanotubes is increasing – reduction. Also, optimal operation conditions is in the area between of defined ranges. Mathematical models of carbon nanotubes quality as a second degree of relationship of the three factors was obtained. Comparison of model results and experimental data reveal that the model can predicate the system behavior well and the only parameters which are unsignificant in the model is the interaction between terms. By using model and design expert7 software, optimal points of synthesis parameters are achieved in catalyst concentration 3.79wt%, temperature 976?C and flow of hydrogen 184 ml / min. In order to obtain the reduction of core growth agglomeration, in the nanotube synthesis stage and optimum conditions, thiophene was used to prevent agglometate cores by space prevented. since the high concentration of sulfur causes toxic catalyst, therefore in optimal conditions of temperature, concentration and flow, several experiments with different concentration of thiophene was done and Thermo Gravimetric Analysis(TGA) reveal that the best amount of thiophene concentration is 2.5wt%. The second part of this thesis is related to a novel ignition method that uses a single exposure of an ordinary camera flash and SWCNTs to ignite various fuels. The effects of the iron (Fe) nanoparticles (embedded in the SWCNTs) concentration and the frequency of flash light on the ignition process have been studied by design expert7 software and central composite design (CCD). The region of Independent parameters of 10-50wt% and 1-5Hz were seleted. The results reveal that in high concentration of iron impurity and low frequency carbon nanotubes were more oxidized. Mathematical model of carbon nanotubes quality as a second degree of relationship of the three factors was obtained. Comparison of model results and experimental data reveal that the model can predict the system behavior well.