A preliminary study on removing vanadium (V) from groundwater using Fe–Mn oxide nanoparticle with different stabilizers

Abstract

The Vanadium V5+ removal from water body and soil is an important issue for environmental protection and conservation. Nanoparticles as adsorption and the stabilizer against nanoaprticle aggregating have become the key problems. The study used simulated experimental method to test the effect of adsorbent Fe-Mn binary oxide nanoparticles with different stabilizers, such as water soluble starch (Starch-Fe-Mn), carboxymethyl cellulose (CMC-Fe-Mn) and no stabilizer (Bare-Fe-Mn) for removing V+5 (10 mg/L) in groundwater, and also to study the absorption characteristic and surface acting mechanism. The results showed that Bare-Fe-Mn is more capacity for removal V+5 than that of starch- Fe-Mn and CMC- Fe-Mn. The absorption rate of Bare-Fe-Mn, starch Fe-Mn and CMC-Fe-Mn can reach to 99% in 1h, 91% in 48hrs and 96% in 48 hrs, respectively. The V+5 absorption processes for Fe-Mn particles with different stabilizers are more accorded with the second-order sorption kinetic model. In 25℃ temperature, V+5 equilibrium adsorption data showed the best fit to the Freundlich isotherm for Fe-Mn particles with different stabilizers. Maximum adsorption occurred at pH 7.0-7.2, Langmuir isotherm model express that the maximum V+5 adsorption capacity was 129.87 mg/g, 120.48 mg/g and 117.65 mg/g for Bare-Fe-Mn CMC-Fe-Mn and Starch-Fe-Mn nanoparticles, respectively. The above change is related closely with pre- and post-absorbed surface features, Zeta potential, FTIR of Fe-Mn nanoparticles with different stabilizers, most important is starch and CMC coating the surface of Fe-Mn nanoparticles and decrease the V+5 ion adsorption. Therefore, Fe-Mn oxide nanoparticles without stabilizer could be considered as an effective material for treating vanadium pollution in aqueous condition.