TEHRAN, Iran, May 23, 2010 -- Nanostructured alumina to remove heavy metals from water was synthesized by an economical method in Semnan University, Iran.
Nanostructured alumina is one of the nanomaterials for which there are different synthesis methods and is used in adsorption of heavy metals from water.
"Nanostructured alumina used in water treatment was synthesized by sol-gel method in the past but the combustion method of solution presented in this study is a low cost and very simple method for removal of pollutants from contaminated waters and wastewaters at higher efficiencies," Akram Rahmani, one of the researchers, said in interview with INIC news service.
Rahmani's investigation results showed that nanostructured alumina synthesized by ammonium acetate fuel has finer particles and bigger pores so that it could be considered as the main adsorbent in heavy metals removal.
The results of analysis of parameters affecting the adsorption quantities implied that the maximum metals removal occurred at pH=4, 180 minutes time period, T=293 K, and 4 gr/l of adsorbent. Thermodynamic studies also revealed that the adsorption process of the mentioned metals on the nanostructured alumina is exothermic and spontaneous.
In this study, Rahmani first synthesized nanostructured alumina by solution combustion method. For this purpose, she used aluminum nitrate as oxidant and urea, acetate, and ammonium nitrate as fuel. She then applied synthesized nanostructured alumina as an adsorbent for removing lead, zinc, and nickel from water in a batch system. She lastly investigated the parameters influencing adsorption such as pH, temperature, time, and adsorbent quantity and studied different isotherms like Langmuir, Freundlich etc.
The details concerning to this research are available at Desalination, volume 253, pages 94-100, 2010.