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G6 Environmental Remediation

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Metal nanoparticles for environmental remediation Signatures

Date:

Member Page

Read from Left to Right, Top to bottom, we have: Brian David Laich, Indiana University of Pennsylvania, Spring 2012 Andrew Ryan Sibley, Bloomsburg University, Fall 2010 Jonathan Lee Demchak Jr, Lock Haven University, Spring 2011 Elizabeth Diane Dusack, Pennsylvania Highlands Community College, Spring 2011 Aleister Tanek Javas Mraz, Pennsylvania State University, Summer 2010

Grading Checklist Group 6: Environmental Remediation Using Metal Nanoparticles GRADING COMMENTS A. Required for all groups Title page with date and group member signatures Member page with pictures, first and last name of each group member This grading checklist DELIVERABLE

Table of contents

Index of figures and graphs

Group statement on what makes an effective group. A

few well written sentences will be adequate. Glossary with relative terms defined. Minimum of 20 terms, at the end of the paper Proper spelling, punctuation, and grammar

A discussion of key concepts, technologies, materials and process of original article Logical flow & overall cohesiveness of paper

Standard in text citation

Reference requirements

Uniform labeling of figures and tables

B. Grading of the following sections will be based on the outline provided Introduction (Abstract)

Physical, Chemical, Biological Descriptions

Creation Methods

Characterization Methods

Iron Particles

Iron Bimetallics

Palladium Compounds

Magnesium Compounds

Zinc Compounds

Conclusion (Details comparisons)

Additional Comments:

ContentsMetal nanoparticles for environmental remediation...................................................1 Member Page..............................................................................................................2 Grading Checklist.......................................................................................................3 Contents.....................................................................................................................9 Index of Figures and Graphs.....................................................................................10 Group Statement......................................................................................................12 Introduction..............................................................................................................13 Physics of Nanoparticles...........................................................................................13 Chemical Interactions and Particle Synthesis...........................................................15 Biological Considerations of Nanoparticles...............................................................17 Health Concerns.......................................................................................................18 Zero Valent Iron Nanoparticles.................................................................................19 Palladium Nanoparticles...........................................................................................41 Magnesium Nanoparticles........................................................................................56 Zinc Nanoparticles....................................................................................................64 Conclusion................................................................................................................72 Bibliography.............................................................................................................83

Index of Figures and Graphs Figure Number 1 2 3 4 5A 5B 6 7 8 9 10 11 12 13 Figure Title Page Number

Image of Iron Nanoparticle (Martin, 2008)...............................................20 Pictograph representing Arsenic Adsorption (Ramos, 2009)....................26 Graphical depiction of Fe/M-2 nanoparticle synthesis (Xu, 2005)...........31 SEM image Fe/Pd BNPs (Xu, 2005).........................................................32 STEM image of agglomerated Fe/Pd nanoparticles (Xu, 2005)...............32 X-EDS image of Fe/Pd BNP (Xu, 2005)..................................................32 Reduction pathway of trichloroethene (Shao-ping, 2005)........................36 TEM image of Fe/Ag BNPs (Luo, 2010)..................................................37 Chart of tetrabromobisphenol A concentration (Luo, 2010).....................39 TEM image of CMC-stabilized Pd nanoparticles (He, 2009)...................45 TEM images of Pd nanoparticles (He, 2009)............................................47 Plot of concentration of TCE catalyzed by CMC-Pd (He, 2009).........49 Au nanoparticles layered with Pd (Wong, 2009)......................................51 Comparison of the TOF of Pd, Pd/Au, and Pd/Al2O3 in presence of chloride and sulfide ions (poisons) (Wong, 2009)................................54

14 15 16 17(a-c) 18 Table 1 Table 2

SEM images of MgO (Nagappa, 2007).....................................................59 SEM images of Mg/Pd powder (Gardner, 2007).......................................60 Degradation of Arochlor 1260 over time (Gardner, 2007)........................61 SEM Images of Zinc nanoparticles (Geuger, 2009)..................................66 Zinc nanoparticle filtration mask (Hsu, 2005)...........................................68 Cost comparison of Pd-Au nanoparticles and Pd-Al2O (Wong, 2009).....55 CONCLUSION. .................................................................................72

Group Statement Building bonds of trust and respect right out of the gate was important to our teams development. In line with this, determining each individuals strengths and weaknesses helped to prepare the group for any academic challenge. A great strength that the group often drew upon was the diversity of each members academic background. Jon and Liz were able to provide biology, Aleister and Brian provided the physics and math, and Andrew added the chemistry to the group. Another key element was our desire to refer to ourselves as G6, a name that helped us set ourselves apart from others, allowing us to push harder and make fun of ourselves from time to time. Born from this group mentality came our group motto, Teamwork makes the dream work!

Introduction There are many positive aspects for the use of metal nanoparticles for in-situ remediation including the target of this work- ground water contaminate dehalogenation. Vinyl chloride {VC}, trichloroethene {TCE}, polychlorinated biphenyls (PCBs), polychlorinated naphthalenes {PCNs}, polychlorinated dibenzo-p-dioxins {Dioxins}, arsenic, tetrabromobisphenol A {TBBPA} , and fluoride can all be removed from ground water using the metal nanoparticles included in this work. Removal of these contaminants through the use of insitu remediation can cut costs of clean up by billions of dollars. Specifically, there are more than 1,200 hazardous waste sites in the U.S. which require immediate action and hundreds of other hazardous waste sites needing to be addressed as well. It has been projected that clean up and decontamination of these superfund sites could take up to 35 years, but through the use of in-situ metal nanoparticles this time could be reduced to a mere 5 years (Burton, 2009).

Physics of NanoparticlesIt is common knowledge that nanoparticles interact very differently than the bulk forms of those particles. This is largely due to the different surface interactions of the atoms of the materials. When nanoparticles are formed, the surface area of the particles is more exposed than the bulk materials because of the reduction in the volume. The reduction in volume is the primary cause for the change in interactions, as it leads to the surface interactions of a particle to dominate the reactions a particle undergoes. This is what causes levels of interactions for nanoparticles to vary depending on the number of atoms that compose a particle.

In solid state physics, a maximum number of surface atoms that insure the minimum volume of a particle is called the magic number. However, for iron based nanoparticles, this is not actually a reflection of the best possible interactions for environmental remediation. The primary ranges for constant high values of interaction of the nanoparticles falls within the range of 18 to 23 atoms of Fe per nanoparticle (Bertolini, 2007). These particle ranges form clusters that exhibit the highest reactivity for environmental remediation, even though the magic number of these particles is at a higher level. This is because past this point multiple layers of particles would develop that hinder in the reactions necessary for the complete dechlorination of contaminated waters. With iron nanoparticles in the correct range, interactions involving the donation of or acceptance of free electrons help to cause the remediation. All of these interactions take place at the surface of the particles and involve the use of iron as a reductant. In some rare cases, iron is used as an oxidant, though for the scope of this paper that is limited to the remediation of arsenic. Other metallic nanoparticles undergo similar reactions at the surface of the materials, with bimetallics being a special case. Bimetallics stand apart from other materials, as the additional metal surfaces create new catalytic reactions that are based upon the interaction of the surface properties of the two materials. The chemical interactions of the nanoparticles follow a simple pattern outlined in the following section of the introduction. The important physical interaction that needs to be noted for metallic nanoparticles is that the magic number does not necessarily apply in determining the best form of the nanoparticl

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