DOCSLIB.ORG

Method for Removing Iodine from Nitric Acid

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Method for Removing Iodine from Nitric Acid 3,803,295 United States Patent Office Patented Apr. 9, 1974 using a diluent carrier isotope as taught by the prior art 3 803 295 was unacceptable for achieving satisfactory iodine re- METHOD FOR REMOVING IODINE FROM moval. NITRIC ACID SUMMARY OF THE INVENTION George I. Gathers and Calvin J. Shipman, Knoxville, Tenn., assignors to the United States of America as 5 It is thus an object of this invention to provide a proc- represented by the United States Atomic Energy Com- ess whereby radioactive iodine may be effectively and mission efficiently removed from nitric acid solutions to concen- No Drawing, Continuation-in-part of application Ser. No. trations which are acceptable for reprocessing require- 231,820, Mar. 6, 1972. This application Dec. 21, 1972, ments. Ser. No. 317,455 10 Int. CI. COlb 7114, 21/44 This object as well as other objects is accomplished U.S. CI. 423—390 8 Claims according to this invention by separating radioactive iodine from nitric acid solutions using isotopic dilution, ozone sparging, and distillation while sparging with a gas ABSTRACT OF THE DISCLOSURE which will reduce nitric acid to an oxide of nitrogen. 15 A method for removing small amounts of radioactive DETAILED DESCRIPTION iodine from nitric acid solution by isotopically diluting the iodine, sparging the solution with ozone, and distilling According to this invention it has been found that the iodine from solution. sparging an isotopically diluted solution with an ozone mixture prior to distillation, produces a solution in which 20 the radioactive iodine is effectively removed upon distil- CROSS REFERENCE TO RELATED APPLICATIONS lation. The reason for this phenomenon is not entirely This is a continuation-in-part of application S.N. 231,- understood; however, the following non-limiting theory 820, filed Mar. 6, 1972. is presented as a possible explanation. The small amount of radioactive iodine remaining in solution after a con- BACKGROUND OF THE INVENTION 25 ventional distillation is probably in a highly oxidized The invention described herein was made in the course state, i.e., either in the iodic or periodic state. When the of, or under, a contract with the United States Atomic nonradioactive iodine diluent is added to the solution, it Energy Commission. is in a lower oxidation state than the radioactive iodine. This invention relates to the art of removing radioac- The differences in the oxidation states prohibit isotopic tive iodine from nitric acid solutions. ^ exchange from occurring. When the solution is sparged In reprocessing fuels from a liquid metal fast breeder with an ozone mixture, the diluent isotope is oxidized to •reactor (LMFBR) it is desirable to dissolve the entire a higher state similar to that of the radioactive isotope, fuel element in nitric acid and to then separate the desired thus facilitating isotopic exchange. radioactive elements one at a time from the solution. The Some of the radioactive iodine is also present as an principal purpose of the reprocessing is to recover urani- organic iodide, such as methyl iodide. The organic iodides um and plutonium for reuse in another fuel element. One are extremely stable and do not release iodine upon distil- of the radioactive elements in solution is iodine as l29I lation. The ozone sparge apparently oxidizes the organic and 131I. The proportions of the activities of these two iodides to leave the iodine in the iodic or periodic state, isotopes vary with time in accordance with their half which will then release iodine upon distillation in accord- lives. In order to protect the environment and operating ance with the method of this invention. personnel from possible exposure to radioactive iodine, As a part of the process of this invention, the iodine it is desirable to separate and isolate the iodine isotopes nitric acid solution is sparged with a gas which will re- from solution prior to further processing. Radioactive duce nitric acid to release an oxide of nitrogen (NO*) iodine is particularly dangerous because of its volatility, during distillation. The preferred sparging gas is N203; and its ability to be carried by vegetation and transmitted however other such gases include N02, S02, H2S, and or- through milk for human ingestion. ganic vapors such as CH3OH. The improved results One prior art method for removing small quantities of which are achieved by using this sparge are consistent a radioactive isotope from solution involves the use of a with the theory presented above. In order for the iodine carrier. A carrier is a material which the radioactive ele- to distill as I2, it is necessary for the oxidized iodine ment will tend to follow. The best carrier for a radioac- 50 species to be reduced. The nitrogen oxide sparge pro- tive element is a nonradioactive isotope of the same ele- motes the reduction of the oxidized iodine species thus ment. making it possible for I2 to be released from the solution In the case of radioactive iodine it was generally during distillation. It is preferred to carry out the sparg- thought that the iodine could be removed from nitric acid gg ing and distillation step at a temperature below the nor- solution by first using conventional distillation followed mal boiling point of the solution. At the normal boiling by isotopic dilution with 127I as a carrier and repeated point of 4 M HNO3 (108° C.) the solubility of NO, further distillation and isotopic dilutions until an ac- gases is very low. The solubility, however, increases ceptably low radioactive iodine concentration was rapidly as the temperature is reduced. The desired chemi- achieved. However, it was discovered that this technique 60 cal reaction is very dependent upon the NOx concentra- was generally ineffective for removing radioactive iodine tion; hence operating at about 105° C. is preferred. How- from nitric acid solutions at molarities of less than about ever, the vapor pressure of the solution is reduced as the 10-6. Apparently upon reaching a low .iodine concentra- temperature is lowered so a lower limit is about 100° C. -6 tion of about 10 M, the remaining radioactive iodine More specifically, according to this invention radioac- is in a nondistillable form, with the result that only the gg tive iodine is removed from nitric acid solutions by first diluent isotope is distilled off while the radioactive isotope distilling about 10 to 20 and preferably about 15% of remains in solution. the volume of a 3 to 6 molar aqueous solution of nitric Reprocessing safety requirements will probably necessi- acid. Under actual plant conditions this original solution tate the removal of radioactive iodine to less than about may have a radioactive iodine molarity of about 10-4. -10 10 molarity for fuels aged less than 30 days and to r,Q After the first distillation, the solution is isotopically di- less than 10-8 molarity for fuels aged more than 30 days. luted with carrier iodine, preferably by adding potassium In view of the above safety requirement, the process of iodide which readily oxidizes to I3. For the sake of con- 3,803,295 3 venience, the carrier iodine is added in an amount such N203 at 300 ml./minute. After a 10 percent cut, the re- that the original iodine concentration is restored. The sidual 131I in solution was 0.0021 percent of the original amount of iodine added, however, must be sufficient to concentration, giving an overall decontamination factor provide a distillable level of iodine, i.e., an iodine molari- of 4.8X104. This leaves a total radioactive iodine molarity ty of at least 2.5 Xl0~5. In order to maintain the nitric of only about 2x 10~18. acid concentration at about 4 M, the original solution In the above example the process of this invention yields volume is preferably restored by adding water to the an overall decontamination factor of 4.8 xlO4 after three solution. distillations. When using the process as taught by the prior At this point, the process of this invention comprises art under similar conditions using only isotopic dilution contacting the isotopically diluted solution with ozonized 10 and distillation without any gas sparging, a decontamina- oxygen to promote isotopic exchange. Preferably, the tion factor of about 100 is achieved after three distilla- oxygen-ozone mixture comprises about 2 volume percent tions. If only the N203 sparge is used, a decontamination ozone; however about 1 to 3 volume percent ozone may factor of about 1200 is achieved. be used. The sparge is conducted at a rate of about 200 It is thus seen that the process of this invention not only 4 ml./minute and preferably 2x 10~ Oa moles per min- overcomes the problems presented by the prior art iso- g 15 ute for 250 ml. of solution, i.e., 10- moles 03/mimite- topic exchange technique but provides a superior method ml., and at a temperature of 70 to 80° C. for a time by which radioactive iodine may be removed from nitric period of from 20 to 30 minutes. acid solutions. Conventional distillation equipment such as that de- What is claimed is: 1 scribed in copending application Ser. No. 231,820 may be 20 1. A method for removing radioactive iodine from used in the distillation steps of this invention. As men- nitric acid solution comprising the steps of isotopically tioned above, improved results are achieved by sparging diluting said solution with nonradioactive iodine to pro- the solution with a nitrogen oxide, preferably N2O3, dur- vide an iodine molarity of at least 2.5 XlO-5, sparging ing distillation. The sparge is carried out at a rate of said solution with ozone, and at a temperature below the about 250 ml./minute and preferably about 4x 10—5 moles 25 normal boiling point of the solution distilling iodine from of N2O3 per minute per ml.
Load more

Recommended publications
  • Environmental Quality: in Situ Air Sparging
    EM 200-1-19 31 December 2013 Environmental Quality IN-SITU AIR SPARGING ENGINEER MANUAL AVAILABILITY Electronic copies of this and other U.S. Army Corps of Engineers (USACE) publications are available on the Internet at http://www.publications.usace.army.mil/ This site is the only repository for all official USACE regulations, circulars, manuals, and other documents originating from HQUSACE. Publications are provided in portable document format (PDF). This document is intended solely as guidance. The statutory provisions and promulgated regulations described in this document contain legally binding requirements. This document is not a legally enforceable regulation itself, nor does it alter or substitute for those legal provisions and regulations it describes. Thus, it does not impose any legally binding requirements. This guidance does not confer legal rights or impose legal obligations upon any member of the public. While every effort has been made to ensure the accuracy of the discussion in this document, the obligations of the regulated community are determined by statutes, regulations, or other legally binding requirements. In the event of a conflict between the discussion in this document and any applicable statute or regulation, this document would not be controlling. This document may not apply to a particular situation based upon site- specific circumstances. USACE retains the discretion to adopt approaches on a case-by-case basis that differ from those described in this guidance where appropriate and legally consistent. This document may be revised periodically without public notice. DEPARTMENT OF THE ARMY EM 200-1-19 U.S. Army Corps of Engineers CEMP-CE Washington, D.C.
    [Show full text]
  • Producing Nitrogen Via Pressure Swing Adsorption
    Reactions and Separations Producing Nitrogen via Pressure Swing Adsorption Svetlana Ivanova Pressure swing adsorption (PSA) can be a Robert Lewis Air Products cost-effective method of onsite nitrogen generation for a wide range of purity and flow requirements. itrogen gas is a staple of the chemical industry. effective, and convenient for chemical processors. Multiple Because it is an inert gas, nitrogen is suitable for a nitrogen technologies and supply modes now exist to meet a Nwide range of applications covering various aspects range of specifications, including purity, usage pattern, por- of chemical manufacturing, processing, handling, and tability, footprint, and power consumption. Choosing among shipping. Due to its low reactivity, nitrogen is an excellent supply options can be a challenge. Onsite nitrogen genera- blanketing and purging gas that can be used to protect valu- tors, such as pressure swing adsorption (PSA) or membrane able products from harmful contaminants. It also enables the systems, can be more cost-effective than traditional cryo- safe storage and use of flammable compounds, and can help genic distillation or stored liquid nitrogen, particularly if an prevent combustible dust explosions. Nitrogen gas can be extremely high purity (e.g., 99.9999%) is not required. used to remove contaminants from process streams through methods such as stripping and sparging. Generating nitrogen gas Because of the widespread and growing use of nitrogen Industrial nitrogen gas can be produced by either in the chemical process industries (CPI), industrial gas com- cryogenic fractional distillation of liquefied air, or separa- panies have been continually improving methods of nitrogen tion of gaseous air using adsorption or permeation.
    [Show full text]
  • "Determination of Total Organic Carbon and Specific UV
    EPA Document #: EPA/600/R-05/055 METHOD 415.3 DETERMINATION OF TOTAL ORGANIC CARBON AND SPECIFIC UV ABSORBANCE AT 254 nm IN SOURCE WATER AND DRINKING WATER Revision 1.1 February, 2005 B. B. Potter, USEPA, Office of Research and Development, National Exposure Research Laboratory J. C. Wimsatt, The National Council On The Aging, Senior Environmental Employment Program NATIONAL EXPOSURE RESEARCH LABORATORY OFFICE OF RESEARCH AND DEVELOPMENT U.S. ENVIRONMENTAL PROTECTION AGENCY CINCINNATI, OHIO 45268 415.3 - 1 METHOD 415.3 DETERMINATION OF TOTAL ORGANIC CARBON AND SPECIFIC UV ABSORBANCE AT 254 nm IN SOURCE WATER AND DRINKING WATER 1.0 SCOPE AND APPLICATION 1.1 This method provides procedures for the determination of total organic carbon (TOC), dissolved organic carbon (DOC), and UV absorption at 254 nm (UVA) in source waters and drinking waters. The DOC and UVA determinations are used in the calculation of the Specific UV Absorbance (SUVA). For TOC and DOC analysis, the sample is acidified and the inorganic carbon (IC) is removed prior to analysis for organic carbon (OC) content using a TOC instrument system. The measurements of TOC and DOC are based on calibration with potassium hydrogen phthalate (KHP) standards. This method is not intended for use in the analysis of treated or untreated industrial wastewater discharges as those wastewater samples may damage or contaminate the instrument system(s). 1.2 The three (3) day, pooled organic carbon detection limit (OCDL) is based on the detection limit (DL) calculation.1 It is a statistical determination of precision, and may be below the level of quantitation.
    [Show full text]
  • The LC Handbook Guide to LC Columns and Method Development Contents
    Agilent CrossLab combines the innovative laboratory services, software, and consumables competencies of Agilent Technologies and provides a direct connection to a global team of scientific and technical experts who deliver vital, actionable insights at every level of the lab environment. Our insights maximize performance, reduce complexity, and drive improved economic, operational, and scientific outcomes. Only Agilent CrossLab offers the unique combination of innovative products and comprehensive solutions to generate immediate results and lasting impact. We partner with our customers to create new opportunities across the lab, around the world, and every step of the way. More information at www.agilent.de/crosslab Learn more The LC Handbook – Guide to LC Columns and Method Development www.agilent.com/chem/lccolumns Buy online www.agilent.com/chem/store Find an Agilent customer center or authorized distributor www.agilent.com/chem/contactus U.S. and Canada 1-800-227-9770 [email protected] Europe [email protected] Asia Pacific [email protected] The LC India [email protected] Handbook Information, descriptions and specifications in this publication are subject to change without notice. Agilent Technologies shall not Guide to LC Columns and be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance or use of this material. Method Development © Agilent Technologies, Inc. 2016 Published in USA, February 1, 2016 Publication Number 5990-7595EN
    [Show full text]
  • Thermal Diffusion Shock Waves in a Linear Temperature Field And
    Thermal Diffusion Shock Waves in a Linear Temperature Field and Comparison of Ultrasonic Distillation to Sparging of Liquid Mixtures by Hyeyun Jung M.Sc., Brown University 2007 B.Sc., Seoul National University 2004 A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Physics at Brown University PROVIDENCE, RHODE ISLAND May 2012 © Copyright 2012 by Hyeyun Jung This dissertation by Hyeyun Jung is accepted in its present form by The Department of Physics as satisfying the dissertation requirement for the degree of Doctor of Philosophy. Date Gerald Diebold, Ph.D., Advisor Recommended to the Graduate Council Date James Valles, Ph.D., Reader Date Xinsheng Sean Ling, Ph.D., Reader Approved by the Graduate Council Date Peter M. Weber, Dean of the Graduate School iii Vita Hyeyun Jung was born on November 29, 1980 in Daegu, Republic of Korea. She com- pleted her secondary education at Wonhwa Girls High School in Daegu in February of 1999. She then attended Seoul National University. She obtained a Bachelor of Science in Chemical Engineering and Physics in February of 2004. In September 2004, she began graduate studies in the Department of Physics at Brown University. She carried out her doctoral research under the supervision of Dr. Gerald J. Diebold. Her publications include: 1. Hyeyun Jung, Vitaly Gusev, Hyoungsu Baek, Yaqi Wang, and Gerald J. Diebold, "Ludwig-Soret Effect in a Linear Temperature Field: Theory and Experiments for Distributions at Long Times", Physics Letters A 375(19), 1917-1920, 2011 2. Hye Yun Jung, Han Jung Park, Joseph M.
    [Show full text]
  • 5310 Total Organic Carbon (Toc)*
    TOTAL ORGANIC CARBON (TOC) (5310)/Introduction 5-19 5310 TOTAL ORGANIC CARBON (TOC)* 5310 A. Introduction 1. General Discussion ular, organic compounds may react with disinfectants to produce potentially toxic and carcinogenic compounds. The organic carbon in water and wastewater is composed of a To determine the quantity of organically bound carbon, the or- variety of organic compounds in various oxidation states. Some ganic molecules must be broken down and converted to a single of these carbon compounds can be oxidized further by biological molecular form that can be measured quantitatively. TOC methods or chemical processes, and the biochemical oxygen demand utilize high temperature, catalysts, and oxygen, or lower tempera- (BOD), assimilable organic carbon (AOC), and chemical oxygen tures (Ͻ100°C) with ultraviolet irradiation, chemical oxidants, or demand (COD) methods may be used to characterize these combinations of these oxidants to convert organic carbon to carbon fractions. Total organic carbon (TOC) is a more convenient and dioxide (CO2). The CO2 may be purged from the sample, dried, and direct expression of total organic content than either BOD, AOC, transferred with a carrier gas to a nondispersive infrared analyzer or or COD, but does not provide the same kind of information. If a coulometric titrator. Alternatively, it may be separated from the repeatable empirical relationship is established between TOC sample liquid phase by a membrane selective to CO2 into a high- and BOD, AOC, or COD for a specific source water then TOC purity water in which corresponding increase in conductivity is can be used to estimate the accompanying BOD, AOC, or COD.
    [Show full text]
  • Compendium Method TO-15
    EPA/625/R-96/010b Compendium of Methods for the Determination of Toxic Organic Compounds in Ambient Air Second Edition Compendium Method TO-15 Determination Of Volatile Organic Compounds (VOCs) In Air Collected In Specially-Prepared Canisters And Analyzed By Gas Chromatography/ Mass Spectrometry (GC/MS) Center for Environmental Research Information Office of Research and Development U.S. Environmental Protection Agency Cincinnati, OH 45268 January 1999 Method TO-15 Acknowledgements This Method was prepared for publication in the Compendium of Methods for the Determination of Toxic Organic Compounds in Ambient Air, Second Edition (EPA/625/R-96/010b), which was prepared under Contract No. 68-C3-0315, WA No. 3-10, by Midwest Research Institute (MRI), as a subcontractor to Eastern Research Group, Inc. (ERG), and under the sponsorship of the U.S. Environmental Protection Agency (EPA). Justice A. Manning, John O. Burckle, and Scott Hedges, Center for Environmental Research Information (CERI), and Frank F. McElroy, National Exposure Research Laboratory (NERL), all in the EPA Office of Research and Development, were responsible for overseeing the preparation of this method. Additional support was provided by other members of the Compendia Workgroup, which include: • John O. Burckle, EPA, ORD, Cincinnati, OH • James L. Cheney, Corps of Engineers, Omaha, NB • Michael Davis, U.S. EPA, Region 7, KC, KS • Joseph B. Elkins Jr., U.S. EPA, OAQPS, RTP, NC • Robert G. Lewis, U.S. EPA, NERL, RTP, NC • Justice A. Manning, U.S. EPA, ORD, Cincinnati, OH • William A. McClenny, U.S. EPA, NERL, RTP, NC • Frank F. McElroy, U.S. EPA, NERL, RTP, NC • Heidi Schultz, ERG, Lexington, MA • William T.
    [Show full text]
  • Air-Sparging Remediation: a Study on Heterogeneity and Air-Mobility
    AIR SPARGING REMEDIATION: A STUDY ON HETEROGENEITY AND AIR MOBILITY REDUCTION 1S.S. Di Julio and 2A.S. Drucker 1California State University, Northridge, Northridge, CA 91330; 1Phone: (805) 667-2496, 1Fax: (805) 667-7062, 1E-mail: [email protected]; 2NFESC, US Navy; 2Phone: (805) 982-4847, 2E-mail: [email protected]. ABSTRACT Contaminated groundwater is a widespread problem often requiring innovative technology to remediate. The purpose of this paper is to present the laboratory results of air sparging models. Initial tests used very fine porous media (glass beads-packed column) to represent a relatively homogeneous soil samples. Subsequent testing employed budded core samples taken from a site of interest to represent more realistic, heterogeneous samples. 1,1,1 Trichloroethane (TCA) was used as the dissolved contaminant to represent BTEX/ gasoline contamination; however, results obtained here can be applied to any NAPL-dissolved phase. A technique based on foam injection is proposed and is demonstrated to reduce air mobility. This reduction in air mobility has potential to improve contaminant removal. Laboratory results are compared with predictions of a numerical model, which is an advection-diffusion air sparge simulation model. Sensitivity analysis of the numerical model provides the range of some key parameters used to screen/evaluate air sparging as the remediation method for a given contaminated site of interest. Eventual scaleup of the model to an actual site application can be justified by the favorable results presented in this paper. Key words: remediation, air sparging, NAPL, foam BACKGROUND scopic capillary air channeling is estimated by The efficiency of air sparging as a ground- Clayton (1998) to occur at air-entry pressure of water remediation process depends to a large about 15 to 20 cm of water.
    [Show full text]
  • Mass Transfer Mechanisms in Air Sparging Systems Washington Jose Braida Iowa State University
    Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1997 Mass transfer mechanisms in air sparging systems Washington Jose Braida Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Agriculture Commons, Civil Engineering Commons, Environmental Engineering Commons, and the Soil Science Commons Recommended Citation Braida, Washington Jose, "Mass transfer mechanisms in air sparging systems " (1997). Retrospective Theses and Dissertations. 12276. https://lib.dr.iastate.edu/rtd/12276 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. INFORMATION TO USERS This manuscript has been reproduced from the microfibn master. UMI fihns the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter &ce, i^e others may be from any type of computer printer. The quality of this reprodaction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI 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. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps.
    [Show full text]
  • PAM I Chapter 6
    Pesticide Analytical Manual Vol. I SECTION 600 Chapter 1 Regulatory Operations Chapter 2 General Analytical Operations and Information Chapter 3 Chapter 4 Multiclass Selective MRMs MRMs Chapter 5 GLC Chapter 6 HPLC Table of Contents page date 601: General Information 601 A: Principles 601-1 1/94 601 B: Modes of Operation 601-2 1/94 Liquid-Solid Chromatography 601-2 1/94 Liquid-Liquid Chromatography 601-3 1/94 Bonded Phase Chromatography 601-3 1/94 Ion Exchange Chromatography 601-4 1/94 Size Exclusion Chromatography 601-4 1/94 601 C: Instrumentation and Apparatus 601-5 1/94 Basic Components 601-5 1/94 HPLC System Plumbing 601-7 1/94 601 D: Solvents and Reagents 601-10 1/94 Potential Problems 601-10 1/94 Specific Solvents 601-12 1/94 Transmittal No. 96-E1 (9/96) Form FDA 2905a (6/92) 600–1 SECTION 600 Pesticide Analytical Manual Vol. I page date Reagent Blanks 601-14 1/94 Safety Precautions 601-14 1/94 601 E: Sample Preparation 601-14 1/94 Sample Cleanup 601-14 1/94 Sample Filtration 601-14 1/94 Sample Solvent Degassing 601-15 1/94 Choice of Sample Solvent 601-15 1/94 601 F: Reference Standards 601-15 1/94 Stock Solutions 601-15 1/94 Working Standard Solutions 601-16 1/94 Storage 601-16 1/94 References 601-16 1/94 602: Columns 602 A: Column Selection 602-1 1/94 602 B: Analytical Columns 602-1 1/94 Liquid-Solid Chromatography 602-2 1/94 Bonded Phases 602-2 1/94 Ion Exchange 602-3 1/94 Ion Pair 602-4 1/94 Size Exclusion 602-4 1/94 602 C: Column Evaluation 602-5 1/94 602 D: Column Specifications 602-6 1/94 602 E: Analytical Column Protection
    [Show full text]
  • Evaluation of the Precision of High-Performance Liquid Chromatography for Wheat Cultivar Identification'
    Evaluation of the Precision of High-Performance Liquid Chromatography for Wheat Cultivar Identification' M. G. SCANLON, H. D. SAPIRSTEIN, and W. BUSHUK' ABSTRACT Cereal Chem. 66(2): 112-116 The reproducibility of computer-derived reversed-phase high- computed peak areas and heights, and percentage peak areas and heights. performance liquid chromatography (RP-HPLC) quantitation parameters Whereas chromatographic resolution was relatively constant over time, following prolonged use of a single commercially available column was prolonged column use significantly retarded peak retention times especially studied. Using a standardized experimental procedure, more than 65 for early eluting components. Results show that without appropriate chromatograms were evaluated based on gliadin extracts from bulk- normalization, peak retention times lack sufficient long-term precision in ground meal and composite grinds of four kernels of the bread wheat order to obtain reliable results for cultivar identification and other RP- cultivar Neepawa. Statistical results are reported for a set of more than 30 HPLC comparative analysis applications. chromatogram peaks with respect to the precision of retention times, The separation of wheat protein extracts by electrophoretic or other quantitation parameter data were transferred to the chromatographic procedures for computerized wheat cultivar University of Manitoba Amdahl 6280 computer for statistical identification and other comparative analysis applications requires analysis. precise quantitative parameters to achieve reliable results (Sapirstein and Bushuk 1985a). Previous studies on the use of Protein Extraction reversed-phase high-performance liquid chromatography (RP- Samples comprising 100 mg of whole wheat meal or four H PLC) for these applications have dealt extensively with pulverized kernels were extracted with 400 pl or a 4:1 ratio of 70% optimization of experimental procedures (Bietz et al 1984, Bietz ethanol in 1.5-ml microcentrifuge tubes.
    [Show full text]
  • Trace Analysis of Volatile Organic Compounds in Water by GC and HPLC Ikue Arikawa Ogawa Iowa State University
    Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1986 Trace analysis of volatile organic compounds in water by GC and HPLC Ikue Arikawa Ogawa Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Analytical Chemistry Commons Recommended Citation Ogawa, Ikue Arikawa, "Trace analysis of volatile organic compounds in water by GC and HPLC " (1986). Retrospective Theses and Dissertations. 8106. https://lib.dr.iastate.edu/rtd/8106 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. INFORMATION TO USERS This reproduction was made from a copy of a manuscript sent to us for publication and microfilming. While the most advanced technology has been used to pho­ tograph and reproduce this manuscript, the quality of the reproduction is heavily dependent upon the quality of the material submitted. Pages in any manuscript may have indistinct print. In all cases the best available copy has been filmed. The following explanation of techniques is provided to help clarify notations which may appear on this reproduction. 1. Manuscripts may not always be complete. When it is not possible to obtain missing pages, a note appears to indicate this. 2. When copyrighted materials are removed from the manuscript, a note ap­ pears to indicate this. 3. Oversize materials (maps, drawings, and charts) are photographed by sec­ tioning the original, begirming at the upper left hand comer and continu­ ing from left to right in equal sections with small overlaps.
    [Show full text]