Evaluating Efficiency of Multi-walled Carbon Nanotubes Modified in Vanadium Removal from Oil Effluent

Vanadium and its compounds are regarded as important environmental pollutants. Due to its damaging effects on human health as well as environmental health, development of new methods for its removal based on new technologies is of extraordinary importance. Therefore, this study aimed to investigate the efficiency of vanadium removal from the effluent collected in the separator tank of Shazand Arak Refinery via the absorbent of modified multi-walled carbon nanotube. This in vitro study was conducted on the oil effluent via the Batch method with concentrations of 3,5,7,9,11,13,15,17,19,21,23 ppm, respectively. The effects of such variables as absorbent amount, initial concentration of vanadium solution, pH, temperature and contact time were assessed on the efficiency of vanadium removal by the absorbent. In order to improve the absorbent’s performance, oxidation process was utilized via nitric acid. Moreover, IR spectra as well as SEM images of absorbent were prepared, and the data were matched with isotherms of the Langmuir, Freundlich, and Temkin. The results of the current study showed that the efficiency of vanadium removal from oil effluent by the absorbent reached 99% at 20°C during 130 min, with adsorbent amount of 0/03g and the optimum pH of 5. In addition, absorption equilibrium of the absorbent was consistent with the Freundlich isotherm (R2= 0/995). The study findings revealed that modified multi-walled carbon nanotube can be utilized as an effective adsorbent for the removal of toxic heavy metals from industrial wastewater.