REMOVAL OF METAL IONS FROM WASTEWATER USING MODIFIED MAGNETIC PARTICLES CARBON NANOTUBES

Abstract

Lead and zinc could be found in wastewater. In order to treat the wastewater before its release to the environmental source, these heavy metals have to be removed. In this work, a new magnetic adsorbent was prepared by loading the Fe3O4 magnetic particles onto carbon nanotubes through co-precipitation method. The amount of Fe3O4 magnetic particles was varied from 20 to 30%wt. The magnetic composite was further modified with 8-hydroxyquinoline solution. The composites were characterized by SEM, TGA and FT-IR. The results showed that the surface of carbon nanotubes was covered by magnetic particles and 8-hydroxyquinoline. The VSM results showed that the adsorbents with 25% and 30% wt magnetic particles and 8-hydroxyquinoline had the magnetization value of 6.726 emu/g and 8.137 emu/g, respectively and the adsorbents that contain only 25% and 30% wt magnetic particles were 15.819 emu/g and 19.907 emu/g, respectively. The composite of MWCNT and magnetic particles with 8-HQ and without 8-HQ (MWCNT-Mag and MWCNT-Mag-8-HQ) were used as adsorbents for Pb(II) and Zn(II) ions adsorption. The time for the adsorption process to reach the equilibrium was 60 minutes and the suitable pH value for metal ions adsorption was pH 5. The adsorption kinetics followed pseudo-second order model and the adsorption equilibrium could be described by Langmuir isotherm. The maximum capacity of MWCNT-30Mag and MWCNT-30Mag-8-HQ in Pb(II) adsorption was 32.26 mg/g and 48.78, respectively. On the other hand, the maximum capacity of MWCNT-Mag and MWCNT-Mag-8-HQ in Zn(II) adsorption was 12.22 and 18.52 mg/g , respectively