Nanoscale zero-valent iron

Liang F, Fan J, Guo Y, Fan M, Wang J, Yang H (2008) Reduction of nitrite by ultrasound-dispersed nanoscale zero-valent iron particles. Ind Eng Chem Res 47(22) 8550-8554... 

Kanel, S., Manning, B., Charlet, L. and Choi, H. (2005) Removal of arsenic(III) from groundwater by nanoscale zero-valent iron. Environmental Science and Technology, 39, 1291-1298. 

Choe S, Chang YY, Hwang KY, Khim J. Kinetics of reductive denitrification by nanoscale zero-valent iron. Chemosphere 2000 41 1307-1311. 

Ponder SM, Darab JG, Mallouk TE. Remediation of Cr(VI) and Pb(II) aqueous solutions using supported, nanoscale zero-valent Iron. Environ Sci Technol 2000 34 2564-2569. 

Adams A. (2006). Transport of nanoscale zero valent iron using electrokinetic phenomena. http //www.sese.uwa.edu.au/ data/page/96395/Adams 2007.pdf Accessed January 16,... 

Chang YI. (2007). Iheatment of Trichloroethylene in Aqueous Solution Using Nanoscale Zero-Valent Iron Emulsion. MS Thesis, National Sun Yat-Sen University, Kaohsiung, Taiwan (in Chinese). 

Kanel SR, Choi H. (2007). Transport characteristics of surface-modified nanoscale zero-valent iron in porous media. Water Science and Technology 55(1-2) 157-162. 

Yang GCC. (2008a). Development and Application of Green Nanotechnology Technology Development and Application of Environmentally Benign Nanoscale Zero-Valent Iron for In Situ Remediation of Simulated Soil/Groundwater Pollution. Final report nr EPA 08496007 (in Chinese). 

Pang SY, Jiang J, Ma J (2011) Oxidation of sulfoxides and arsenic(III) in corrosion of nanoscale zero valent iron by oxygen evidence against ferryl ions (Fe(IV)) as active intermediates in Fenton reaction. Environ SciTechnol 45 307-312... 

Reductive dechlorination of HCB can be achieved with the combination of electrokinetics with the appropriate catalysts such as nanoscale zero valent iron (NZVl). The electric field can be used as a mechanism for the delivery of NZVl into the soil [10]. Reductive dechlorination can be achieved in the soil or even upon the cathode if the contaminant reaches the cathode compartment. Other metallic catalysts such as Cu/Fe or Pd/Fe bimetal microscale particles were satisfactorily used with the same purpose. Dechlorination of hexachlorobenzene up to 98 % was achieved with Cu/Fe [27] and only 60 % with Pd/Fe [20]. 

Cobalt and nickel porphyrins have also been used for catalyzing the chemical dechlorination with a reductant, namely titanium(III) citrate or nanoscale Zero Valent Iron (nZVI), of e.g. atrazine, (2-chloro-4-(ethylamine)-6-(isopropylamine)-s-triazine), a widely used herbicide which is a persistent groundwater contaminant [38]. Nickel 5,10,15,20-tetrakis(l -methyl-4-pyridinium)porphyrintetra(p-toluene-sulfonate) (TMPyP) was activated by nZVI, while cobalt porphyrins (TMPyP,5,10,15,20-tetrakis(4-hydroxyphenyl)-21 H,23H-porphine-(TP(OH)P) and 4,4, 4",4 -(porphine-5,10,15,20-tetrayl)tetrakis (benzenesulfonic acid)-(TBSP)) were activated by titanium(lll) citrate as the electron donor. All these processes probably could be more efficient using electrochemical methods. 

Attention has been particularly devoted to the application of nanoscale particles of zero-valent iron, and a range of halogenated aliphatic compounds has been examined. 

Lin, Y., Weng, C. and Chen, F. (2008) Effective removal of AB24 dye by nano/ micro-size zero-valent iron. Separation and Purification Technology, 64, 26-30. Wang, C.B. and Zhang, W.X. (1997) Synthesizing nanoscale iron particles for rapid and complete dechlorination of TCE and PCBs. Environmental Science and Technology, 31, 2154-2156. 

Zhang and Wang (1997) studied the reaction of zero-valent iron powder and palladium-coated iron particles with trichloroethylene and PCBs. In the batch scale experiments, 50 pL of 200 pg/mL PCB-1254 in methanol was mixed with 1 ml ethanol/water solution (volume ratio = 1/9) and 0.1 g of wet iron or palladium/iron powder in a 2-mL vial. The vial was placed on a rotary shaker (30 rpm) at room temperature for 17 h. Trichloroethylene was completely dechlorinated by the nanoscale palladium/iron powders within the 17-h time period. Only partial dechlorination of PCB-1254 was observed when wet iron powder was used. 

If dried the particles become too reactive to use in groundwater remediation All of the above What is the advantage of using nanoscale iron in comparison to commercially available powdered zero-valent iron ... 

Module 2 Using nanoscale bimetallic iron particles for groundwater remediation. This module has been created according to existing literature. Trichloroethylene (TCE), one of the most ubiquitous soil and groundwater contaminants, is used as a sample contaminant. The reductive dehalogenation of TCE via zero-valent nano iron particles can be described by the following equation (29) ... 

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