Conversion of toxic hexavalent chromium to trivalent chromium by rhamnolipid stabilized zero valent iron nanoparticles

Nasser, Fatima (2013). Conversion of toxic hexavalent chromium to trivalent chromium by rhamnolipid stabilized zero valent iron nanoparticles. University of Birmingham. M.Res.

Preview

Nasser13PhD.pdf
PDF - Accepted Version
Download (1MB)

Abstract

Zero valent iron nanoparticles (nZVI) are being used in environmental remediation of contaminants due to their reducing properties. Toxic chemicals such as hexavalent chromium (Cr(VI)) are released into environmental waters from industrial effluent and are capable of triggering life threatening diseases in humans. Solution phase Cr(VI) has can be converted to less harmful trivalent chromium (Cr(III)) using nZVI, which decreases the oxidation state. Cr(III) binds to iron and can be removed, thereby decreasing the concentration of solution phase Cr(VI). The nZVI have a high specific surface area though aggregate in solution which decreases specific surface area. In this study rhamnolipid surfactant capped nZVI of 50 nm were synthesized and were compared to nZVI without any incorporated surfactant using various characterization methods. At 10mg/L rhamnolipid incorporated nZVI and maintained a core size of 50 nm whilst raw nZVI z-average diameter increases from 341 nm to 1993 nm forming micron sized nZVI aggregates. It was determined that 1 gram of micro sized nZVI was able to convert 3 mg of Cr(VI) whilst 1 gram of nZVI was able to convert 36 mg in the same time period indicating that rhamnolipid was able to disperse particles and increase efficiency of the reaction.

Type of Work:

Thesis (Masters by Research > M.Res.)

Award Type:

Masters by Research > M.Res.

Supervisor(s):