DOCSLIB.ORG

ABSTRACT FEI, XIUZHU. Towards Closed Loop

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
ABSTRACT FEI, XIUZHU. Towards Closed Loop ABSTRACT FEI, XIUZHU. Towards Closed Loop Recycling of Polyester Fabric. (Under the direction of Dr. Harold S. Freeman and Dr. David Hinks). Polyethylene terephthalate (PET) is extensively used in various types of apparel, home textiles, and outdoor products that are regularly placed in landfills after use. But unlike natural fibers, PET is not readily biodegradable. In view of sustainability, research regarding the recycling of textiles derived from PET fibers is of interest, and effective color removal has been recognized as a crucial step towards recycling of colored PET fabrics. To this end, a decolorization process was developed using sodium formaldehyde sulfoxylate (SFS) as the reducing agent. Disperse dye decolorization studies were conducted in water and acetone media, and an optimized combination of treatment time (30 min), water to acetone ratio (1:2), SFS concentration (10g/L), temperature (100oC), and liquor ratio (1:50) was found effective for decolorizing various commercial disperse dyes as well as basic dyes. Results in terms of intrinsic viscosity of decolorized PET showed that the optimized SFS decolorization method has no significant effect on fiber strength. The goal of this work was to study the recyclability of bath and fabric after decolorization, investigate the ecotoxicity of the decolorization process, study the life cycle assessment of the closed-loop recycling process, characterize dyes from commercial fabrics and study their decolorization properties. Fabric decolorization using the optimized SFS method followed by re-dyeing using Disperse Yellow 42, Disperse Orange 30, Disperse Red 60, and Disperse Blue 79 was conducted on cationic dyeable PET. It was found that fabrics containing nitro and anthraquinone dyes, Disperse Yellow 42 and Disperse Red 60, respectively, have better decolorization efficiency than those containing azo Disperse Orange 30 and Disperse Blue 79 dyed fabrics. Bearing in mind that ecotoxicity testing is of increasing importance in the screening of newly developed substances or treatment processes, solutions of six high volume disperse dyes and one basic dye were decolorized using SFS, and the resultant solutions were tested with Daphnia similis and Parhyale hawaiensis to observe the acute toxicity to the two species. The control sample, which is the SFS solution without dyes, showed that EC50 to Daphnia similis is 1.83%, and LC50 to Parhyale hawaiensis is 9.0%. EC50 and LC50 were expressed in percentage of dye solution. Decolorized dye solutions differed in the toxicity, however, the differences were not significant. The toxicity observed in the acute tests is probably mainly related to SFS decolorization medium. Converting EC50 and LC50 of decolorized solution to equivalent concentration, the effluents were considered relatively harmful to Daphnia similis. Control SFS solution and decolorized Disperse Blue 56 were moderately toxic to Parhyale hawaiensis, whereas decolorized Disperse Orange 30 was relatively nontoxic to Parhyale hawaiensis. A closed loop recycling of PET fabric was proposed beginning with collection of post- consumer PET fabrics/garments, followed by chemical decolorization, mechanical reprocessing, and ending with production of recycled PET fibers. A life cycle assessment was conducted to compare the innovative closed loop recycling process and virgin PET production process. Results suggest that recycled PET production has less environmental impacts than the virgin system in six categories, namely, exotoxicity, eutrophication, human health- carcinogenics, human health-non-carcinogenics, ozone depletion, and respiratory effects, but also shows higher impact results in four categories, which are acidification potential, global warming potential, photochemical ozone formation potential, and fossil fuels resource depletion. Contribution analysis shows higher impacts in those four categories result from the consumption of acetone. Sensitivity analysis also shows that overall impact is sensitive to acetone consumption, which means environmental benefits of the recycling method are highly dependent on the acetone consumptions. This life cycle assessment is conducted based on a hypothetical closed-loop scenario. Further work on obtaining specific data in innovative recycling processing for more reliable analysis would be beneficial. © Copyright 2018 by Xiuzhu Fei All Rights Reserve Towards Closed Loop Recycling of Polyester Fabric by Xiuzhu Fei A dissertation submitted to the Graduate Faculty of North Carolina State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy Fiber and Polymer Science Raleigh, North Carolina 2018 APPROVED BY: _______________________________ _______________________________ Dr. David Hinks Dr. Harold S Freeman Co-chair of Advisory Committee Co-chair of Advisory Committee _______________________________ _______________________________ Dr. Nelson Vinueza Dr. Joseph DeCarolis ii DEDICATION I dedicate my dissertation work to Dr. Harold S. Freeman and Dr. David Hinks for their guidance and support over the years. I also dedicate this work to my parents, my sister, brother in law, and my beloved, Ju Dong. iii BIOGRAPHY Xiuzhu Fei was born in Shaoxing, Zhejiang Province of China in 1991. Shaoxing is a medium size city that relied heavily on textile industry 15 years ago. Many of her relatives were working for textile companies. However, due to the increasing regulations and restrictions, the traditional labor-intensive textile plants and mills lost their competitiveness in recent years. She chose the Dyeing and Finishing Engineering as her major in Jiangnan University, because she wanted to learn more about textiles and bring some benefits to her hometown. Later she was enrolled to North Carolina State University in August 2013 as a master student majoring in Textile Chemistry. Afterwards she was enrolled in the Fiber and Polymer Science Program to pursue a PhD degree. She believes sustainable textiles are the future of the textile world. iv ACKNOWLEDGMENTS Writing this note of thanks is the finishing touch on my dissertation. It has been several years of learning in North Carolina State University, Raleigh, not only in the scientific area, but also on a personal level. I would like to express my sincere acknowledgements to the people who have supported and helped me so much throughout this period. I would first like to thank Dr. David Hinks for founding me throughout my research career. I have never imaged I could study abroad before I received an offer letter from Dr. Hinks 5 years ago. I am deeply grateful for the opportunity. He covered me all the time so I could focus on the research. Without his support, this PhD work would not have been achievable. My greatest appreciation goes to Dr. Harold S. Freeman for all the guidance, instruction and encouragement he gave me during the time I spent at the NC State. He is a very patient and responsible professor. I will always keep every piece of hand-written feedback he gave to me about my thesis and manuscripts. He pointed me to the right direction so that I can successfully complete my dissertation. He is also a considerate person which inspires me a lot in my personality. I would also like to thanks Dr. Nelson Vinueza and Dr. Joseph DeCarolis for their excellent cooperation as kindly being my committee members. I sincerely appreciate the helpful suggestions and comments I received from them. A very special thanks to previous and current group members in Dr. Hinks’s and Dr. Freeman’s research group, especially Dr. Malgorzata Szymczyk, for their help in the lab work and for their companionship in my life. v Finally, many thanks go to my parents, sister and brother in law, for believing in me and supporting me all the time; to all my dear friends for bringing me happiness and joy; and to my dear boyfriend Ju, for his selfless love. vi TABLE OF CONTENTS LIST OF TABLES .............................................................................................................. x LIST OF FIGURES ..........................................................................................................xii 1. INTRODUCTION ............................................................................................................. 1 2. LITERATURE REVIEW .................................................................................................. 3 2.1 Polyethylene terephthalate ........................................................................................... 3 2.1.1 Introduction to polyethylene terephthalate ............................................................. 3 2.1.2 Properties of polyesters ......................................................................................... 5 2.2 Coloration of polyester ................................................................................................ 7 2.2.1 Disperse dyes ........................................................................................................ 8 2.2.2 Basic dyes ........................................................................................................... 14 2.3 Dye characterization .................................................................................................. 16 2.3.1 Ultraviolet-visible spectroscopy .......................................................................... 16 2.3.2 Chromatography ................................................................................................. 17 2.3.3 Mass spectrometry
Load more

Recommended publications
  • Download (4Mb)
    University of Warwick institutional repository: http://go.warwick.ac.uk/wrap A Thesis Submitted for the Degree of PhD at the University of Warwick http://go.warwick.ac.uk/wrap/53126 This thesis is made available online and is protected by original copyright. Please scroll down to view the document itself. Please refer to the repository record for this item for information to help you to cite it. Our policy information is available from the repository home page. Synthesis and application of thiourea-S,S-dioxide derivatives by James Frederick Shuan-Liang Apps A thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Chemistry University of Warwick Department of Chemistry February 2008 To my parents ii Table of Contents Abstract .............................................................................................................................. 1 Abbreviations ...................................................................................................................... 2 Chapter 1. Introduction .................................................................................................... 5 1.1 Preface .......................................................................................................................... 5 1.2 Oxidation of sulfur compounds ..................................................................................... 7 1.3 Thiourea oxides in biological systems ........................................................................ 10 1.4 Structure,
    [Show full text]
  • Recent Developments on the Origin and Nature of Reductive Sulfurous Off-Odours in Wine
    fermentation Review Recent Developments on the Origin and Nature of Reductive Sulfurous Off-Odours in Wine Nikolaus Müller 1,* and Doris Rauhut 2 1 Silvanerweg 9, 55595 Wallhausen, Germany 2 Department of Microbiology and Biochemistry, Hochschule Geisenheim University, Von-Lade-Straße 1, 65366 Geisenheim, Germany; [email protected] * Correspondence: [email protected]; Tel.: +49-6706-913103 Received: 9 July 2018; Accepted: 3 August 2018; Published: 8 August 2018 Abstract: Reductive sulfurous off-odors are still one of the main reasons for rejecting wines by consumers. In 2008 at the International Wine Challenge in London, approximately 6% of the more than 10,000 wines presented were described as faulty. Twenty-eight percent were described as faulty because they presented “reduced characters” similar to those presented by “cork taint” and in nearly the same portion. Reductive off-odors are caused by low volatile sulfurous compounds. Their origin may be traced back to the metabolism of the microorganisms (yeasts and lactic acid bacteria) involved in the fermentation steps during wine making, often followed by chemical conversions. The main source of volatile sulfur compounds (VSCs) are precursors from the sulfate assimilation pathway (SAP, sometimes named as the “sulfate reduction pathway” SRP), used by yeast to assimilate sulfur from the environment and incorporate it into the essential sulfur-containing amino acids methionine and cysteine. Reductive off-odors became of increasing interest within the last few years, and the method to remove them by treatment with copper (II) salts (sulfate or citrate) is more and more questioned: The effectiveness is doubted, and after prolonged bottle storage, they reappear quite often.
    [Show full text]
  • Thiosulfate Degradation During Gold Leaching In
    THIOSULFATE DEGRADATION DURING GOLD LEACHING IN AMMONIACAL THIOSULFATE SOLUTIONS : A FOCUS ON TRITHIONATE By NOELENE AHERN B.Sc, University of Natal, 1994 B.Sc. (Hons), University of Natal, 1995 M.A.Sc, University of Cape Town, 1997 A thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Faculty of Graduate Studies (Materials Engineering) The University of British Columbia October 2005 © Noelene Ahern, 2005 ABSTRACT Thiosulfate has shown considerable promise as an alternative to cyanide for gold leaching. However, one of the main limitations of the thiosulfate system is the high consumption of thiosulfate. Besides increasing the cost of the process, the degradation products of thiosulfate have been claimed to passivate gold surfaces and the polythionates often produced are loaded onto resins proposed for gold recovery. The thiosulfate degradation process is not completely understood. Of the degradation products, trithionate is a concern in the resin recovery of gold and is persistent in gold leach solutions. Very little is known about the expected behaviour of trithionate, both with respect to its formation and its interaction with other solution species. The focus of this work was therefore to further the understanding of the behaviour of trithionate in gold leach solutions. Experimental work was carried out to determine the kinetics of trithionate degradation in systems resembling gold leaching solutions, and a kinetic model was derived for trithionate degradation. The rate of degradation of trithionate in aqueous ammoniacal solutions was expressed by Equation 1. 2 + 2 -d[S306 -]/dt = (k3[NH4 ] + k2[NH3] + k,[OHl + k0)[S3O6 T [1] 1 1 1 1 1 where k0 = 0.012 h"\ = 0.74 IvV.h;, k2 = 0.0049 M" .h' , k3 = 0.01 M" .^ .
    [Show full text]
  • Hydrogen from Hydrogen Sulfide Ryan J. Gillis
    Theory and Applications for Sulfur Chemistry: Hydrogen from Hydrogen Sulfide by Ryan J. Gillis B.S., Brigham Young University (2015) Submitted to the Department of Chemical Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemical Engineering at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY September 2020 ○c Massachusetts Institute of Technology 2020. All rights reserved. Author................................................................ Department of Chemical Engineering July 30, 2020 Certified by. William H. Green Professor Thesis Supervisor Accepted by . Patrick S. Doyle Graduate Officer, Department of Chemical Engineering 2 Theory and Applications for Sulfur Chemistry: Hydrogen from Hydrogen Sulfide by Ryan J. Gillis Submitted to the Department of Chemical Engineering on July 30, 2020, in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemical Engineering Abstract In this thesis, I explore the chemistry of reacting sulfur species computationally and experimentally. The computational work centers around creating the capability to automatically predict the thermochemical properties of arbitrary sulfur molecules and the kinetic parameters of reactions between these species. A demonstration of this enhanced capability is shown in the automatic creation of detailed chemical mech- anism describing the partial oxidation of dimethyl sulfide. The experimental work focuses on a hydrogen generating chemical cycle that uses a hydrogen sulfide feed- stock. Initially exploring the reactivity of hydrogen sulfide, water, and iodine mixtures to form hydroiodic acid, two competing pathways were discovered. The more inter- esting pathway involved the reaction of hydrogen sulfide with iodine and water to form hydroiodic acid and sulfur dioxide. A bench-top prototype was created demon- strating the creation of hydrogen gas from hydrogen sulfide through this pathway.
    [Show full text]
  • ABSTRACT FEI, XIUZHU. Decolorization of Dyed Polyester
    ABSTRACT FEI, XIUZHU. Decolorization of Dyed Polyester Fabrics using Sodium Formaldehyde Sulfoxylate. (Under the direction of Dr. David Hinks and Dr. Harold S. Freeman). Polyethylene terephthalate (PET) fiber is now the largest single fiber type within global textile production, taking over from cotton. In view of environmental stewardship, an effective approach to recycling colored PET fabrics has drawn wide attention. A key step in the recycling process is dye removal. Disperse dyes are used to dye PET fibers and designed to be durable inside the fiber. In addition, disperse dyes are hydrophobic and will not be substantially extracted with water as the only solvent. In this work, the organic solvent, acetone, was used in combination with water to remove disperse dyes from the PET, and sodium formaldehyde sulfoxylate (SFS) was employed to decolorize the dye. This agent was found effective for decolorizing Disperse Yellow 42, Yellow 86, Blue 56 and Blue 60 in acetone/water solutions and the process was extended to decolorization of dyed PET. An optimized combination of treatment time (30 min), water to acetone ratio (1:2), SFS concentration (10g/L), temperature (100 ˚C), and liquor ratio (1:50) was found to give sufficient color removal for a broad range of disperse dyes. Reuse of the water/acetone medium for five times was achieved for decolorization of Disperse Yellow 42 but could not be achieved for Disperse Blue 56. Fabric strength assessments were also investigated. It was found that SFS decolorization has no adverse influence on PET strength, as judged by viscosity measurements. © Copyright 2015 Xiuzhu Fei All Rights Reserved Decolorization of Dyed Polyester Fabrics using Sodium Formaldehyde Sulfoxylate by Xiuzhu Fei A thesis submitted to the Graduate Faculty of North Carolina State University in partial fulfillment of the requirements for the degree of Master of Science Textile Chemistry Raleigh, North Carolina 2015 APPROVED BY: _______________________________ _______________________________ Dr.
    [Show full text]
  • Sodium Dithionite Cas N°: 7775-14-6
    OECD SIDS SODIUM DITHIONITE FOREWORD INTRODUCTION SODIUM DITHIONITE CAS N°: 7775-14-6 OECD SIDS SODIUM DITHIONITE SIDS Initial Assessment Report For SIAM 19 Berlin, Germany, 19-22 October 2004 1. Chemical Name: Sodium dithionite 2. CAS Number: 7775-14-6 3. Sponsor Country: Germany Contact Point: BMU (Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit) Contact person: Prof. Dr. Ulrich Schlottmann Postfach 12 06 29 D- 53048 Bonn 4. Shared Partnership with: 5. Roles/Responsibilities of BASF AG = lead company the Partners: • Name of industry sponsor BASF AG, Germany /consortium Contact person: Dr. Hubert Lendle GUP/CL – Z 570 D-67056 Ludwigshafen • Process used The BUA Peer Review Process : see next page 6. Sponsorship History • How was the chemical or by ICCA-Initiative category brought into the OECD HPV Chemicals Programme? 7. Review Process Prior to last literature search (update): the SIAM: 14 February 2003 (Human Health): databases medline, toxline; search profile CAS-No. and special search terms 5 February 2004 (Ecotoxicology): databases CA, biosis; search profile CAS-No. and special search terms OECD/ICCA 8. Quality check process: As basis for the SIDS-Dossier the IUCLID was used. All data have been checked and validated by BUA. A final evaluation of the human health part has been performed by the Federal Institute for Risk Assessment (BfR) and of the ecotoxicological part by the Federal Environment Agency (UBA). 9. Date of Submission: Deadline for circulation: 23 July 2004 10. Date of last Update: 11. Comments: OECD SIDS SODIUM DITHIONITE OECD/ICCA - The BUA* Peer Review Process Qualified BUA personnel (toxicologists, ecotoxicologists) perform a quality control on the full SIDS dossier submitted by industry.
    [Show full text]
  • IUPAC Provisional Recommendations] 2 ] 2 2 2 +D O 2 − − 3 Osi(O) ] ]
    1 Table IR-8.1 Acceptable common names and fully systematic (additive) names for oxoacid and related structures. (March 2004) This Table includes compounds containing oxygen and hydrogen and at least one other element and with at least one OH group; certain isomers; and examples of corresponding partially and fully dehydronated anions. Formulae are given in the classical oxoacid format with the 'acid' (oxygen-bound) hydrogens listed first, followed by the central atom(s), then the hydrogen atoms bound directly to the central atom, and then the oxygen atoms (e.g. HBH2O, H2P2H2O5), except for chain compounds such as e.g. HOCN. In most cases formulae are also written as for coordination entities, assembled according to the principles of Chapter IR-7 (e.g. the Table gives 'HBH2O = [BH2(OH)]' and 'H2SO4 = [SO2(OH)2]'). More names of oxoanions are given in Table IX. Note that Section P-42 of Ref. 1 lists a great many inorganic oxoacid structures for use as parent structures in the naming of organic derivatives, cf. the discussion in Section IR-8.1. Most of those structures, but not all, are included here; a number of di- and polynuclear acids are not explicitly included. Formula Common name Fully systematic additive name(s) (unless otherwise stated) a H3BO3 = [B(OH)3] boric acid trihydroxidoboron − − H2BO3 = [BO(OH)2] dihydrogenborate dihydroxidooxidoborate(1−) − 2− HBO32 = [BO2(OH)] hydrogenborate hydroxidodioxidoborate(2−) 3− − [BO3] borate trioxidoborate(3 ) (HBO2)n = (B(OH)O)n metaboric acid catena-poly[hydroxidoboron-µ-oxido] − n− (BO2
    [Show full text]
  • Nomenclature of Inorganic Chemistry (IUPAC Recommendations 2005)
    International Union of Pure and Applied Chemistry Nomenclature of Inorganic Chemistry IUPAC RECOMMENDATIONS 2005 Issued by the Division of Chemical Nomenclature and Structure Representation in collaboration with the Division of Inorganic Chemistry Prepared for publication by Neil G. Connelly Ture Damhus University of Bristol, UK Novozymes A/S, Denmark Richard M. Hartshorn Alan T. Hutton University of Canterbury, NewZealand University of Cape Town, South Africa IR-9.3 COORDINATION COMPOUNDS IR-9.3.2.2 Choosing between closely related geometries For real molecules or ions, the stereochemical descriptor should be based on the nearest idealizedgeometry. However, someidealized geometries are closely related [ e.g. square planar ( SP-4), four-coordinate square pyramidal ( SPY- 4), see-saw ( SS-4), and tetrahedral ( T-4);T-shaped ( TS- 3), trigonalplanar ( TP-3), and trigonalpyramidal ( TPY-3)] and care may therefore be requiredinmaking the choice. The following approach is useful in determining the polyhedralsymbol for four- coordinate structures. The key is to consider the locations of the central atom and the coordinating atoms in relation to each other. If all five atoms are in (or are close to beingin) the same plane, then the molecule should be treated as square planar. If the four coordinating atoms are in aplane, but the central atom is significantly displaced from the plane, then the squarepyramidal geometry is appropriate.Ifthe four coordinating atoms do not lie in (or close to) aplane, then apolyhedron can be defined by joiningall four coordinating atoms togetherwith lines. If the central atom lies inside this polyhedronthe molecule shouldberegarded as tetrahedral, otherwise, it should be regarded as having a see-saw structure.
    [Show full text]
  • SUMMARY of the INVENTION of a Salt of an Oxy Acid of Sulfur Wherein
    3,597,456 thirds water. Such a mixture is preferred as higher con 3,597,456 METHOD FOR PREPARNG STERILE LECTHEN centrations of lecithin tend to be difficult to handle, while Charles Rifkin, Highland Park, and Rudolfo Cilento, lower concentrations require excessively large vessels North Brunswick, N.J., assignors to E. R. Squibb & and involve heating excessive amounts of water. It is Sons, Inc., New York, N.Y. 5 to be understood, however, that the foregoing considera No Drawing. Filed May 20, 1969, Ser. No. 826,258 tions are primarily economic, not chemical, and it is em Int, CI. A237/00; C07f 9/02 phasized that the present invention is applicable to any U.S. C. 260-403 9 (Claims aqueous mixture of lecithin and water. The sterilizing conditions comprise elevated tempera tures and pressures. The temperatures are suitably above ABSTRACT OF THE DISCLOSURE 10 100 C. and the pressures are at least atmospheric and The presence of from 0.1 to 5% by weight of a salt of Suitably superatmospheric. The upper limit of the steri an oxy acid of sulfur wherein the apparent oxidation state lizing conditions is the decomposition point of the lecithin. of the sulfur is not greater than -- 4 prevents color In practice, there is little or no advantage in temperatures degradation during the sterilization of lecithin. above about 130° C. or pressures above a few atmos ls pheres. The lecithin is generally treated at these elevated temperatures and pressures for upwards of fifteen min BACKGROUND OF THE INVENTION utes,minutes. typically from about thirty minutes to about sixty The present invention relates to the sterilization of According to the present invention the sterilizing treat lecithin, and more particularly, to a method of sterilizing ment is carried out in the presence of a small amount lecithin whereby color degradation is prevented.
    [Show full text]
  • The Institute of Paper Chemistry
    The Institute of Paper Chemistry Appleton, Wisconsin Doctor's Dissertation Effects of pH and Oxidizing Agents on the Rate of Absorption of Hydrogen Sulfide into Aqueous Media C. Neal Carter January, 1966 I EFFECTS OF pH AND OXIDIZING AGENTS ON THE RATE OF ABSORPTION OF HYDROGEN SULFIDE INTO AQUEOUS MEDIA A thesis submitted by C. Neal Carter B.S. 1961, North Carolina State University M.S. 1963, Lawrence College in partial fulfillment of the requirements of The Institute of Paper Chemistry, for the degree of Doctor of Philosophy from Lawrence University, Appleton, Wisconsin Publication Rights Reserved by The Institute of Paper Chemistry January, 1966 TABLE OF CONTENTS Page SUMMARY 1 INTRODUCTION 3 BACKGROUND OF THE THESIS PROBLEM 5 Tne Aqueous Hydrogen Sulfide System 5 Thermodynamic Considerations 5 Physical Equilibrium 5 Chemical Equilibrium 10 Reaction Considerations 10 Hypochlorite Oxidation 11 Kinetic Considerations 17 Rate of Dissociation 17 Rate of Reaction with Hydroxyl Ion 18 Rate of Oxidation 18 The Penetration Theory of Gas Absorption 19 The Mathematical Model 19 Physical Absorption 20 Absorption with Chemical Reaction 21 Penetration Theory as Applied to Hydrogen Sulfide Absorption 24 Previous Work 24 Information from Gas Absorption Measurements 24 APPARATUS AND PROCEDURES 25 The Secondary Experiments 25 Physical Properties of Absorbents 25 Solubility Measurements 25 Static Method 25 Dynamic Method 26 iii Diffusivity Measurements 26 Free Boundary Techniques 27 Electrophoresis-Diffusion Apparatus Procedure 27 Ultracentrifuge Apparatus
    [Show full text]
  • MARLAP Manual Volume II: Chapter 14, Separation Techniques (PDF)
    14 SEPARATION TECHNIQUES 14.1 Introduction The methods for separating, collecting, and detecting radionuclides are similar to ordinary analytical procedures and employ many of the chemical and physical principles that apply to their nonradioactive isotopes. However, some important aspects of the behavior of radionuclides are significantly different, resulting in challenges to the radiochemist to find a means for isolation of a pure sample for analysis (Friedlander et al., 1981). While separation techniques and principles may be found in standard textbooks, Chapter 14 addresses the basic chemical principles that apply to the analysis of radionuclides, with an emphasis on their unique behavior. It is not a comprehensive review of all techniques. This chapter provides: (1) a review of the important chemical principles underlying radiochemical separations, (2) a survey of the important separation methods used in radiochemistry with a discussion of their advantages and disadvantages, and (3) an examination of the particular features of radioanalytical chemistry that distinguish it from ordinary analytical chemistry. Extensive examples have been provided throughout the chapter to illustrate various principles, practices, and procedures in radiochemistry. Many were selected purposely as familiar illustrations from agency procedural manuals. Others were taken from the classical and recent radiochemical literature to provide a broad, general overview of the subject. This chapter integrates the concepts of classical chemistry with those topics unique to radio- nuclide analysis. The first eight sections of the chapter describe the bases for chemical separations involving oxidation-reduction, complex-ion formation, distillation/volatilization, solvent extraction, precipitation and coprecipitation, electrochemistry, and chromatography. Carriers and tracers, which are unique to radiochemistry, are described in Section 14.9 together with specific separation examples for each of the elements covered in this manual.
    [Show full text]
  • (12) United States Patent (10) Patent No.: US 6,552,141 B1 Chmelir Et Al
    USOO65521.41B1 (12) United States Patent (10) Patent No.: US 6,552,141 B1 Chmelir et al. (45) Date of Patent: Apr. 22, 2003 (54) METHOD FOR PRODUCING SYNTHETIC (56) References Cited POLYMERIZATES WITH VERY LOW RESIDUAL MONOMER CONTENT U.S. PATENT DOCUMENTS 4,766,173 A * 8/1988 Bailey et al. ............... 524/819 (75) Inventors: Miroslav Chmelir, Krefeld (DE); Kurt Dahmen, Moenchengladbach (DE) 4,929,717 A * 5/1990 Chmelir ...................... 528/490 4,954,562 A 9/1990 Anderson ................... 524/430 4,985,518 A 1/1991 Alexander et al. .......... 526/240 (73) Assignee: Stockhausen GmbH & Co. KG, 5,264,471. A 11/1993 Chmelir ....................... 524/35 Krefeld (DE) 5,684,106 A 11/1997 Johnson et al. ............. 526/295 (*) Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 FOREIGN PATENT DOCUMENTS U.S.C. 154(b) by 0 days. DE 19529348 A 2/1997 (21) Appl. No.: 09/554,098 EP OSO5163 A 9/1992 (22) PCT Filed: Nov. 13, 1998 * cited by examiner (86) PCT No.: PCT/EP98/07289 Primary Examiner J. Zalukaeva S371 (c)(1), (74) Attorney, Agent, or Firm-Oblon, Spivak, McClelland, (2), (4) Date: Jun. 14, 2000 Maier & Neustadt, P.C. (87) PCT Pub. No.: WO99/26987 (57) ABSTRACT PCT Pub. Date:Jun. 3, 1999 The invention relates to a method for producing water (30) Foreign Application Priority Data soluble or water-swellable polymerizates with a low residual monomer content from acrylic acid and/or acrylic acid Nov. 25, 1997 (DE) ......................................... 197 52 127 derivatives. The method is characterized by the addition of (51) Int.
    [Show full text]