Comparison of Efficiency of Nano-magnetic Iron, Single-walled Carbon Nanotubes and Hybrid Nano-reactor in Removal of Xylene from Aqueous Solutions and Adsorption Isotherms

Xylene, which can pollute the water sources, is widely used as a solvent in insecticide manufacture, dye and leather and other industries. Adsorption is one of the most common processes used to treat the contaminated aqueous solutions by xylene. Therefore, the aim of this study was to compare the xylene removal efficiency and adsorption isotherms of magnetic nanoparticles (iron nanoparticles), single-walled carbon nanotube (SWCNT) and single-walled carbon nanotubes- magnetic nanoparticles (SWCNT-MN) hybrid adsorbent.

The variables studied in this research were xylene concentration, adsorbent dosage, contact time and pH. In this study, the xylene removal was evaluated by SWCNT-MN hybrid nanoreactors for 2 to 20 minutes. Design Expert software was used to optimize the xylene removal factors using Taguchi OA method. Xylene adsorption isotherm was investigated by ISOFIT software. Xylene measurement was performed by GC/MS.

The efficiency of the xylene removal by magnetic Fe3O4 nanoparticles, SWCNT and SWCNT-MN were 99.8, 99.2 and 99.9%, respectively. The Xylene adsorption isotherm of these three adsorbents showed that GLG isotherm is the most suitable isotherm for this adsorption.

The efficiency of the xylene removal by SWCNT-MN nano-reactors had no significant difference with the efficiency of the nano-magnetic column, but the removal efficiency of the xylene by the SWCNT-MN nano-reactors column and the nano-magnetic column was significantly different from the SWCNT column. Also, the comparison of adsorption capacity of used adsorbents showed that SWCNT-MN nanoreactors had the higher adsorption capacity than magnetic nanoparticles and SWCNTS.