Nanotechnology for Environmental Remediation

by Joo, Sung Hee; Cheng, I. Francis

• ISBN13: 9780387288253
• ISBN10: 0387288252
• Format: Hardcover
• Copyright: 2006-02-14
• Publisher: Springer Verlag

Summary

The book examines the suitability of nanoscale zero-valent iron (ZVI) for degradation of agrochemicals for the purpose of developing a cost-effective treatment technology. It identifies by-products produced from the ZVI-mediated degradation process of particular contaminants, and clarifies the reaction mechanism by which ZVI degrades a chosen contaminant. It also assesses how the ZVI-based technology may be applied in complex, natural systems, the limitations to implementation, and possible avenues for further research which might improve the viability of the process.

Table of Contents

Preface	v
Acknowledgments	vii
Abbreviations and Symbols	xiii
Chapter 1. Introduction	1	(4)
1.1. Objectives	2	(1)
1.2. Outlines	3	(2)
Chapter 2. Literature Review	5	(20)
2.1. Zero-Valent Iron (ZVI)	5	(7)
2.1.1. Iron Use in the Environment	5	(2)
2.1.2. Nanoparticulate Bimetallic and Iron Technology	7	(1)
2.1.3. Permeable Reactive Barrier (PRB) Using Granular ZVI	8	(1)
2.1.4. PRB and ZVI Colloids	9	(1)
2.1.5. Use of ZVI, H2O2, and Complexants	10	(1)
2.1.6. Nanosized ZVI (nZVI)	11	(1)
2.2. Pesticides and Contamination	12	(10)
2.2.1. Introduction	12	(1)
2.2.2. Characteristics of Pesticides and Their Environmental Effects	13	(3)
2.2.3. Commonly Used Pesticides	16	(2)
2.2.4. Pesticides Treatment and Management Practices	18	(4)
2.3. Summary	22	(3)
Chapter 3. Nanoscale ZVI Particles Manufacture and Analytical Techniques	25	(16)
3.1. Synthesis of Nanoscale ZVI Particles	25	(3)
3.1.1. ZVI Particle Characterization	26	(2)
3.2. Analytical Techniques	28	(7)
3.2.1. Solid-Phase Microextraction GC/MSD	28	(6)
3.2.2. HPLC Analysis of Benzoic Acid and p-Hydroxybenzoic Acid	34	(1)
3.2.3. Measurement of Ferrous Iron Concentrations	34	(1)
3.2.4. Measurement of Hydrogen Peroxide (H2O2) Concentrations	34	(1)
3.3. Procedures Used in nZVI-Mediated Degradation Studies	35	(2)
3.3.1. Molinate Degradation	35	(1)
3.3.2. Benzoic Acid Degradation	36	(1)
3.4. Experimental Setup Used in ZEA System Studies	37	(2)
3.5. Determination of ZVI Surface Products by XRD	39	(2)
3.5.1. Measurements in the Presence of Molinate	40	(1)
3.5.2. Measurements in the Absence of Molinate	40	(1)
Chapter 4. Oxidative Degradation of the Thiocarbamate Herbicide, Molinate, Using Nanoscale ZVI	41	(42)
4.1. Introduction	41	(1)
4.2. Results	41	(17)
4.2.1. Effect of the Presence of Air/Oxygen	41	(1)
4.2.2. Effect of Molinate and ZVI Concentration	42	(2)
4.2.3. Effect of pH	44	(1)
4.2.4. Ferrous Iron Generation	45	(7)
4.2.5. Effect of DO	52	(1)
4.2.6. Hydrogen Peroxide Generation	53	(2)
4.2.7. Catalase and Butanol Competition	55	(1)
4.2.8. Degradation By-products	56	(2)
4.3. Molinate Degradation by Combined ZVI and H2O2	58	(6)
4.3.1. Effect of ZVI at Fixed Hydrogen Peroxide Concentration	60	(1)
4.3.2. Effect of Hydrogen Peroxide at Constant ZVI	60	(1)
4.3.3. Degradation By-products by Combined ZVI and H2O2	61	(3)
4.3.4. Fe(II) Generation from Coupled ZVI/H2O2 in the Presence of Molinate	64	(1)
4.4. Molinate Degradation Using Fenton's Reagent	64	(5)
4.4.1. Degradation By-products of Molinate Using Fenton's Reagents	67	(2)
4.5. Comparison of ZVI, Coupled ZVI/H2O2 and Fenton's Process at High pH	69	(1)
4.6. XRD and XPS Analysis	69	(4)
4.6.1. Results of XRD Analysis	69	(4)
4.6.2. XPS Results	73	(1)
4.7. Discussion	73	(7)
4.7.1. Evidence of Oxidation Pathway	73	(2)
4.7.2. Reaction Mechanism	75	(4)
4.7.3. Kinetics of Fe(II) and H2O2 Generation	79	(1)
4.7.4. Overview of the ZVI-Mediated Oxidative Technology	79	(1)
4.8. Conclusion	80	(3)
Chapter 5. Molecular Oxygen Activation by FeII/III EDTA as a Form of Green Oxidation Chemistry*	83	(14)
5.1. Oxygen Activation	83	(2)
5.2. Xenobiotic Degradation by ZEA System	85	(2)
5.3. Mechanism of Degradation	87	(1)
5.4. Rate-Determining Step	88	(3)
5.5. Iron Chelation and Chelate Geometry Influence Reactivity	91	(3)
5.6. Form of Reactive Oxygen Intermediate Species	94	(1)
5.7. Conclusion	95	(2)
Chapter 6. Quantification of the Oxidizing Capacity of Nanoparticulate Zero-Valent Iron and Assessment of Possible Environmental Applications	97	(26)
6.1. Introduction	97	(1)
6.2. Results	98	(22)
6.2.1. p-Hydroxybenzoic acid (p-HBA) Formation	98	(1)
6.2.2. Cumulative Hydroxyl Radical Formation over Long Term	98	(2)
6.2.3. Effect of Fe(II) as Oxidant Scavenger	100	(1)
6.2.4. Effect of ZVI Concentrations on Oxidant Yield	101	(2)
6.2.5. Effect of pH	103	(1)
6.2.6. Selectivity of Oxidant	103	(6)
6.2.7. Effect of ZVI Type on Oxidant Yields	109	(1)
6.2.8. Comparison Study on Standard Fenton Oxidation of Benzoic Acid	109	(1)
6.2.9. Effect of Pure O2 on Oxidant Yield	110	(3)
6.2.10. Discussion	113	(2)
6.2.11. Conceptual Kinetic Modeling	115	(5)
6.3. Conclusion	120	(3)
Chapter 7. Conclusions and Future Research Needs	123	(6)
7.1. Column Studies	123	(1)
7.2. Further Applications of the ZVI-Mediated Oxidative Process	124	(1)
7.3. Summary of Results	125	(2)
7.4. Overview of nZVI Research and Further Research Needs	127	(2)
Chapter 8. References	129	(18)
Appendix A: XRD Analysis of ZVI Collected from Four Different Samples	147	(2)
Appendix B: XRD Analysis of ZVI Collected from Four Different Samples	149	(2)
Appendix C: ELISA Analysis Methodology	151	(4)
Appendix D: Oven Programs for GC/MS Analysis of Pesticides	155	(2)
Appendix E: Experimental Conditions for Pesticides and Preliminary Screening Studies Using Nanoscale ZVI	157	(6)
Index	163