Paper Title
Removal of Toluene, Ethyl Benzene and O – Xylene from Aqueous Solutions using Carbon Nano Tubes Prepared by Floating Catalytic Chemical Vapor Deposition Method

Volatile Organic Compounds (VOCs) are major air pollutants, emitted largely by various industries, motor vehicles and in households. Many VOCs are toxic and some are carcinogenic, mutagenic, or teratogenic. Besides health effects, these compounds also contribute to the formation of ozone (O3; a secondary pollutant) in ambient air. Toluene, Ethyl Benzene and Xylene are listed as priority pollutants by WHO (WHO, 2000). Hence it becomes necessary to mitigate these pollutants. The hexagonal arrays of sp2-like carbon atoms in the tubular graphene sheets on the surfaces of CNTs provide a favorable morphological structure for adsorbing aromatic compounds. Thus, the present study is aimed at preparation, characterization of novel carbon nano tubes using floating catalytic chemical vapor deposition method its application towards toluene, ethyl benzene and o-xylene (TEX) removal. CNTs were prepared using a mixture of benzene and ferrocene as hydrocarbon source. Ferrocene played a role as a floating catalyst and hydrocarbon source. The main novelty in this work is the preparation of CNTs without any substrate. The prepared CNTs ranged from 50 to 80 nm in width and few micrometers in length. The specific surface area was found to be 109 m2/g. The prepared material was applied to the successful removal of Toluene, ethyl benzene and O-Xylene from aqueous solutions. Adsorption of TEX by lab CNTs were found to be constant irrespective of initial pH of the aqueous solution. The rate of adsorption of TEX on lab CNTs was very fast and within 20 min equilibrium was reached. The kinetics followed pseudo second order kinetics with correlation coefficient > 99%. Further from static adsorption test it was found that the adsorption capacity followed the order O-Xylene > Ethyl Benzene > Toluene. Keywords - Carbon Nano Tubes, VOC, Decontamination, Adsorption, Waste Water