REMOVAL OF COPPER(T) AND LEAD(II) FROM SOILS BY POLY(AMIDOAMINE) DENDRIMERS AND REDUCTIVE IMMOBILIZATION OF CHROMIUM(VI) BY STABILIZED ZERO-VALENT IRON NANOPARTICLES Except where reference is made to the work of others, the work described in this dissertation is my own or was done in the collaboration with my advisory committee. This dissertation does not include proprietary or classified information. Yinhui Xu Certificate of approval: Mark O. Barnett Dongye Zhao, Chair Associate Professor Associate Professor Civil Engineering Civil Engineering T.
Prabhakar Clement Zhongyang Cheng Associate Professor Assistant Professor Civil Engineering Materials Engineering Jacob H. McFarland Professor Acting Dean Agronomy and Soils Graduate School REMOVAL OF COPPER(T) AND LEAD(D FROM SOILS BY POLY(AMIDOAMINE) DENDRIMERS AND REDUCTIVE IMMOBILIZATION OF CHROMIUM(VD BY STABILIZED ZERO-VALENT IRON NANOPARTICLES Yinhui Xu A Dissertation Submitted to the Graduate Faculty of Auburn University in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Auburn, Alabama August 7, 2006 UMI Number: 3225299 INFORMATION TO USERS The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleed-through, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted.
Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. ® UMI UMI Microform 3225299 Copyright 2007 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code.
ProQuest Information and Learning Company 300 North Zeeb Road P. Box 1346 Ann Arbor, MI 48106-1346 REMOVAL OF COPPER(T) AND LEAD(D FROM SOILS BY POLY(AMIDOAMINE) DENDRIMERS AND REDUCTIVE IMMOBILIZATION OF CHROMIUM(VD BY STABILIZED ZERO-VALENT IRON NANOPARTICLES Yinhui Xu Permission is granted to Auburn University to make copies of this thesis at its discretion, upon request of individuals or institutions and at their expense. The author reserves all publication rights. Signature of Author Date of Graduation iii VITA Yinhui (Lucida) Xu, daughter of Jinsong Xu and Chuanfeng Yao, was born in the city of Tai-An, Shandong, China.
and an MLS. in Environmental Engineering in 1999 and 2002, respectively, both from Donghua University in Shanghai, China. After a brief seven months of employment with the DuPont Fibers Ltd. In Shanghai, she ventured to cross the Ocean to pursue her Ph.
degree at Auburn University in Fall 2002. During the four years stay at Auburn, She feels so blessed and fortunate to have harvested a great deal both personally and academically. She was married to Baojian Guo in 2003, and then became the happiest Mom of their lovely daughter Lucy Y. Guo a year later.
She produced five papers in prominent journals such as ES&T, JEE, I&EC Res., and Water Res., and three publications/presentations at various national/international conferences. She feels humbled and honored to be selected as a recipient of five eminent awards including the CH2M HILL Fellowship Award (2004), AWEA Outstanding Graduate Student Scholarship Award (2006), AWWA AL- MS Outstanding Graduate Student Scholarship Award (2006), AU Outstanding International Student Award (2006), and ACS Geochemistry Symposium’s Outstanding Student Paper Award (2006). iv DISSERTATION ABSTRACT REMOVAL OF COPPER(I) AND LEAD(IT) FROM SOILS BY POLY(AMIDOAMINE) DENDRIMERS AND REDUCTIVE IMMOBILIZATION OF CHROMIUM(VI) BY STABILIZED ZERO-V ALENT IRON NANOPARTICLES Yinhui Xu Doctor of Philosophy, August 7, 2006 (M. Donghua University, China, 2002) (B.
Donghua University, China, 1999) 237 Typed Pages Directed by Dongye Zhao This research investigated the feasibility of using poly(amidoamine) PAMAM dendrimers for removal of copper(II) and lead(1I) from soils, and using a new class of stabilized zero-valent iron (ZVI) nanoparticles for reductive immobilization of chromium (VI) in contaminated soils. PAMAM dendrimers ranging from generation (G) 1.5 and with —NH;, -COO, and -OH terminal groups were tested for extraction of copper(II) and lead(II) from a sandy loam soil, a clay soil, and a sandy clay loam. A series of fixed- bed column experiments were conducted to study the effects of dendrimer dosage, generation number, functional groups, pH, ionic strength, and soil type on the removal efficiency. It was found that more than 90% of the preloaded copper (II) was removed by ~66-bed volumes a dendrimer solution containing 0.5 dendrimer with -COOH terminal groups and at pH 6.
Approximately 92% of the initially sorbed lead (II) was removed by ~ 120 bed volumes containing 0.5 dendrimer with -COONa terminal groups at pH 4. The spent dendrimers were recovered through nanofiltration and then regenerated with 2 N hydrochloric acid. The recovered dendrimers were then reused and showed comparable metal removal effectiveness to that of fresh dendrimers. An ion-exchange based approach was developed to determine the apparent stability constants of the CudI)- or Pbd])-dendrimer complexes.
The method was derived by modifying the traditional Schubert ion exchange method, but offered a number of advantages, including the application of a non-linear reference isotherm and extension of the classical approach from mono-nuclear to poly-nuclear complexes. To simulate the dynamic metal removal process by dendrimers, a two-site model was formulated. The model envisions the soil sorption sites as two distinguished fractions: one with a fast desorption rate and the other with a slow desorption rate. The model was able to not only simulate the elution histories of lead and copper by various dendrimers, but also prove promising to predict the metal elution histories under various conditions such as initial metal concentration in soil, dendrimer dosage, and solution pH.
An innovative in situ technology for reductive immobilization of Cr(VI) was tested. A new class of stabilized zero-valent iron (ZVI) nanoparticles was prepared using sodium carboxymethyl cellulose (CMC) as a stabilizer. Batch and column experimental results revealed that the ZVI nanoparticles could effectively reduce Cr(V]) to Cr(II]), and reduce the Cr leachability by ~90%. vl ACKNOWLEDGEMENTS I would like to express my sincere appreciation to my advisor, Dr.
Dongye Zhao, for his supervision, guidance, support, and patience throughout my Ph. The experience of working with him over the last four years in Auburn leaves me wonderful memories to appreciate for the rest of my life. I want to thank my committee members, Dr. Cheng, and Dr.
Dane, and my dissertation outside reader Dr. Yucheng Feng for providing unconditional support and valuable suggestions during the studies. I feel fortunate that I met them and had a chance to work with them. I would also like to express my love and gratitude to my husband for his endurance, infinite support, and loving care.
I wish to thank my daughter for bringing me happiness and joy in the last one and half years. Finally, I wish to thank my parents and other family members for their support. It is their constant encouragement that made this dissertation possible. vii Style manual or journal used — Auburn University manuals and guides for the preparation of theses and dissertations: Organizing the manuscript — publication format Computer software used Microsoft Word & Excel 2002; EndNote 8.0; and Compaq Visual Fortran 6.
Vili TABLE OF CONTENTS LIST OF TABLES. HH TH TH HH ĐH HH nhủ XIV LIST OF FIGUREES. HT TH HH TH HH nhủ XVI CHAPTER 1. SG HS HH ng Hy 1 1.1 Soil Contamination by Heavy MetalÌS.
LH TH TH kg vu 1 1.2 Current Remediation Methods for Heavy Metal Contaminated SolÏs.1 Isolation, containment, solidification, and stabilization. SH TT TH TH nọ nh ng ng kh 4 1.5 Soil flushing and soil Washing .ccc vn v vn ng vê 4 1.3 Nano-Technology in Environmental Clean-up .cc c1 S2 vs vs vệ 5 1.1 Nanosorbents and nanocafaÏySfS.ccc cv ng ng yên 6 1.2 Poly(amidoamine) PAMAM dendr1ers.3 Zero-Valent Iron (ZVI) nanoparticles .5 Organization of This Dissertation. REMOVAL OF COPPER FROM CONTAMINATED SOIL BY USE OF POLY(AMIDOAMINE) DENDRIMERS.2 Materials and ProcedUF€S.-- -L Lcc HH SH ng TK TK ky 17 2.3 Results and [DIS€USSIOTI. TH HH HH nh 25 2.1 Titration curves of denir1I€TS.2 Copper ii) (à 0c oi o0 5PIIada.3 Copper binding capacity of dendr1YS.4 Copper sorption / desorption isotherms for the SOIÏ.5 Cu removal at various dendrimer concenTafIOTIS.6 Effects Of PH oo.7 Effects of terminal group type.8 Effects of dendrimer Øø€n€rafIOn.c ng HH khu44 2.9 Effects of ionic strength.10 Effect on copper speciation in SOIÏ .11 Recovery and reuse of spent dendr1me€rS.
REMOVAL OF LEAD FROM CONTAMINATED SOILS USING POLY(AMIDOAMINE) DENDRIMERS. L2 SH vn n1 1k rệt 52 3. c1 HT KH ket 52 3.2 Materials and Mletho.c- nL SH TT TH ng KT kg 56 3.3 Results and Discussion na.1 Sorption and desorption of lead by SOIÌS.2 Lead removal at various dendrimer concentrations .3 Lead removal using dendrimers of different terminal functional groups.4 Effect of dendrimer Ø€r€r8fiOII. cv v1 vn ng vn 73 3.5 Effect Of PH.6 Impact of dendrimer treatment on Pb”” speciation and leachability .7 Dendrimer retention by soil and recovery of spent dendrimers.4 Summary and Con€ÏUSIO'S.
cv HH TS ng HH ng và 85 CHAPTER 4. A REVISED ION EXCHANGE METHOD FOR ESTIMATION OFCONDITIONAL STABILITY CONSTANTS OF METAL-DENDRIMER COMPLEXES. LH TH TH TH HT Ki HH TH kg 87 4. TH TH HH nọ KT nọ TT nh 87 4.2 Materials and \MethOdS.
-- c2 SH TH HH TH kh 91 4. - - c1 TH TH ki nọ TH TH nh 96 4.3 Results and [DIS€USSIOT. HH TH HH HH kh 99 4. LG HH TH HH ng 99 4.2 Metal sorption isotherMs .-- 111112 111kg sgk như 101 4.3 Complexation of Cu** with G1.0-NH: at pH 5.4 Complexation of Cu”” with dendrimers of various generations .5 Complexation of Pb”” with G1.
MODELING THE ELUTION HISTORIES OF COPPER AND LEAD FROM A CONTAMINATED SOIL TREATED BY POLY(AMIDOAMINE) (PAMAM) DENDRIMERS.-Q LH ng TH ng kg kh 114 Š. c0 1n ng ng HHKH ket 114 S V80 ïnnưatiitỔ. ng ng KH TH TH kệ 117 V802 2n) nen aảj4.- -- - c1 112 vn TT ng 120 5.4 Results and ]DDISCUSSIOTI.- Ặ- Ăn TH TH TH KH ng kg 125 5.1 Simulating Cu7*/Pb”* tranSpOT.2 Predicting the Cu””/Pbf” elution histories.5 Summary and Con€ÏUSIOTS. <1 ng TK HT gà 142 CHAPTER 6.
REDUCTIVE IMMOBILIZATION OF CHROMATE IN WATER AND SOIL BY STABILIZED TRON NANOPARTICLES. LH TH nu TH HH KH ng vp 144 6.2 Materials and IMetho. co TH TH HH HH kh 147 6.3 Results and DISCUSSIOTI. Q1 TH HH nọ ng 151 6.1 Reduction of Cr(VI) in water by Fe nanoparticles.2 Reduction of Cr(VI) sorbed in SOIÏ.3 Reductive immobilization of Cr(V]) in soil: column tests.
CONCLUSIONS AND SUGGESTIONS FOR FUTURE RESEARCH 10117 .2 Suggestions for Future WOTĂK. L1 vn 111g 1v kg tk ng ven 170 ;ì351›45) 9077 .:‹+%E 173 APPENDIX A FORTRAN CODE FOR TRACER TEST. c7 2c ccScsssersseves 201 APPENDIX B IMPLICIT METHOD FOR ONE-SITE MODEL.‹+5s5< +52 203 Xii APPENDIX C IMPLICIT METHOD FOR GAMMA-DISTRIBUTION MODEL. 207 APPENDIX D IMPLICIT METHOD FOR TWO-SITE MODEL.
eee 211 APPENDIX E RUNGE-KUTTA METHOD FOR BATCH METAL RELEASE WITH TWO-SITE MODEÌL. 7 011221111 vn ng KT kg 215 Xili LIST OF TABLES Table 2-1. Salient Properties of Dendrimers Used in the Copper Removal Study. Compositions of a Loamy Sand Soil Used in Copper Removal Study.
Reagents and Conditions Used in the Sequential Extraction. Copper Distribution between a Chelating lon Exchange Resin (DOW 3N) and Water with or without Dendrimer,. Best-fitted Langmuir Model Parameters and R° Values for the Three Dendrimers and a Loamy Sand Soil. Copper Removal and Effluent pH under Various Experimental Conditions.
Copper Speciation in Original and Dendrimer-Treated So1Ï. Salient Properties of Dendrimers Used for Lead Removal. Major Compositions of Soils Used for Lead Removal. Best-Fitted Freundlich Model Parameters and Rˆ Values for the Two Soils.
Lead Removal and Effluent pH Following Various Treatments of Three SOUS. Recovery of Spent Dendrimers and Pb’” in the Spent Dendrimer Eluent. Salient Properties of Dendrimers Used in the Lead Removal Study. Important Properties of the lon Exchange ReSINS.
Percentage of Dendrimer Loss from the Aqueous Phase under Various Conditions (data given as mean of duplicates + standard deviation).