OPTIMIZATION OF REACTION CONDITION FOR PRODUCTION OF CARBON NANOTUBES USING CONTINUOUS ROTARY REACTOR SYSTEM

Abstract

Carbon nanotubes (CNTs) is discovered in decades ago, however the commercial applications of CNTs have not been fully realized yet. The reasons lie in two interrelated aspects: the difficulty in mass production of CNTs and hence the high production cost. Previously, a horizontal rotary reactor was successfully developed for the continuous and large-scale production of CNTs via catalytic chemical vapor deposition of methane. In this study, the independent process parameters, i.e. reaction temperature, methane partial pressure, catalyst feed rate and catalyst residence time, were investigated using response surface methodology approach, which focused on investigation of the effects of process parameters on the carbon content, and were optimized simultaneously using numerical optimization method based on the experimental results obtained. The optimum operating condition obtained was a reaction temperature of 833 °C, reaction time of 165 minutes, methane partial pressure of 0.54 atm and catalyst amount of 260 mg/min. The carbon deposits synthesized under optimum reaction condition had high carbon content of 95.40 wt%, equivalent to carbon yield of 2073.9%. The carbon deposits were solely CNTs with diameter distribution of 10.18±1.02 nm and ID/IG ratio of 1.262. The carbon deposition rate of approximately 323 gCNTs/hr based on the catalyst feeding rate of 260 g/min was achieved.