DOCSLIB.ORG

Summary 1 Diss. No. 20813 Catalytic Urea Decomposition, Side-Reactions

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Summary 1 Diss. No. 20813 Catalytic Urea Decomposition, Side-Reactions Summary Diss. No. 20813 Catalytic urea decomposition, side-reactions and urea evaporation in the selective catalytic reduction of NOx A dissertation submitted to ETH ZURICH for the degree of Doctor of Sciences presented by ANDREAS MANUEL BERNHARD M.Sc., University of Berne Born April 29th, 1984 citizen of Seeberg accepted on the recommendation of Prof. Dr. A. Wokaun, examiner Prof. Dr. J. A. van Bokhoven, co-examiner Dr. O. Kröcher, co-examiner 2012 1 Summary 2 Summary Acknowledgements I would like to thank Prof. Dr. Alexander Wokaun for giving me the opportunity to carry out this thesis at Paul Scherrer Institut and for accompanying the thesis by regular meetings. I thank Dr. Oliver Kröcher a lot for the supervision, for providing advice and for proofreading all my reports and publications. I thank Prof. Dr. Jeroen van Bokhoven for taking the task as co-examiner. I am grateful for the constant support by Martin Elsener. He helped me with experimental work, but also with data analysis and interpretation. I thank Dr. Izabela Czekaj for performing DFT calculations to make an important contribution to two of my publications. I would like to thank my fellow PhD student Dr. Daniel Peitz for his tremendous effort on method development. I’m grateful to Dr. Tilman Schildhauer for bringing in his expertise in chemical engineering. I also thank the former and present group members Dr. Max Mehring, Lukas Bächli, Dr. Sandro Brandenberger, Dr. Maria Casapu, Dr. Tinku Baidya, Valentina Marchionni, Dr. Anastasios Kampolis, Dr. Davide Ferri, the internship student David Sherwood and all the other colleagues who contributed to this thesis or helped me in another way. My special thanks are directed to the industry partner TOTAL (France) for funding. Finally, I thank my parents who have always supported me. 3 Summary Table of contents Summary .................................................................................................................. 8 Zusammenfassung ................................................................................................ 10 Abbreviations and general formulae .................................................................. 12 1. Introduction ................................................................................................... 13 1.1. Background .............................................................................................. 13 1.2. Selective catalytic reduction of NOx .................................................... 16 1.2.1. NH3-slip vs. DeNOx curves ........................................................... 17 1.3. NH3-supply .............................................................................................. 19 1.4. Urea thermolysis and evaporation ........................................................ 21 1.5. Urea decomposition byproducts and catalyst deactivation .............. 25 1.6. Catalytic urea decomposition ................................................................ 27 1.6.1. Anatase TiO2 ..................................................................................... 29 1.7. Scope of the presented Thesis .............................................................. 29 2. Experimental .................................................................................................. 32 2.1. Setup for investigations on NH3-precursors ...................................... 32 2.1.1. Process scheme and heating ........................................................... 32 2.1.2. Gas mixing ........................................................................................ 34 2.1.3. Dosing of the liquid reducing agent .............................................. 35 2.1.4. HNCO generation for HNCO hydrolysis experiments ............. 37 2.1.5. Reactor ............................................................................................... 38 2.1.6. Monoliths .......................................................................................... 40 2.1.7. FTIR spectroscopy: existing method ............................................ 41 2.1.8. Extension of the FTIR spectroscopy method by urea, EtOH and MeOH ..................................................................................................... 43 4 Summary 2.1.9. Method testing: urea-SCR in the laboratory ................................ 48 2.1.10. Method testing: reproducibility ..................................................... 51 2.1.11. Method testing: spray evaporation ............................................... 54 2.2. Liquid-quench of the product gas ........................................................ 58 2.3. HPLC analysis ......................................................................................... 60 2.4. TPD experiments .................................................................................... 63 2.4.1. Setup ................................................................................................... 63 2.4.2. Monoliths .......................................................................................... 65 2.4.3. Experiment types ............................................................................. 66 2.5. Chemicals ................................................................................................. 68 2.6. Catalyst preparation and characterization ........................................... 69 3. Urea evaporation at atmospheric pressure ................................................ 72 3.1. Introduction ............................................................................................. 72 3.2. Experimental and theoretical details .................................................... 75 3.2.1. Measuring procedure ....................................................................... 75 3.2.2. Computational details ...................................................................... 77 3.3. Results ....................................................................................................... 77 3.3.1. Desorption of urea under TPD conditions ................................. 77 3.3.2. FTIR spectrum of monomolecular urea ...................................... 81 3.3.3. Desorption of urea at constant temperature ............................... 85 3.3.4. Conclusions ....................................................................................... 91 4. Urea hydrolysis and side-reactions on titanium dioxide .......................... 92 4.1. Introduction ............................................................................................. 92 4.2. Experimental ........................................................................................... 94 4.3. Results and Discussion .......................................................................... 96 5 Summary 4.3.1. Overview ........................................................................................... 96 4.3.2. Urea hydrolysis ................................................................................. 98 4.3.3. Biuret decomposition .................................................................... 101 4.3.4. Melamine hydrolysis ...................................................................... 111 4.3.5. Hydrolysis and de-polymerization of CYA ................................ 114 4.3.6. CYA formation ............................................................................... 117 4.4. Conclusions ........................................................................................... 120 5. Urea adsorption on titanium dioxide ....................................................... 122 5.1. Introduction ........................................................................................... 122 5.2. Experimental and theoretical details .................................................. 124 5.2.1. DRIFT samples and catalyst coating .......................................... 124 5.2.2. Adsorption and thermolysis of gaseous urea on TiO2 ............. 125 5.2.3. HPLC analysis ................................................................................ 126 5.2.4. DRIFT measurements ................................................................... 127 5.2.5. Computational details .................................................................... 127 5.3. Results and Discussion ........................................................................ 128 5.3.1. Confirmation of urea adsorption by HPLC analysis ................ 128 5.3.2. Quasi-stationary thermolysis of gaseous urea on a TiO2-coated monolith ........................................................................................................ 130 5.3.3. DRIFT measurements at 80°C .................................................... 131 5.3.4. Comparison of DRIFT measurements with DFT calculations .... .......................................................................................................... 136 5.3.5. Urea thermolysis followed by DRIFT spectroscopy ................ 141 5.4. Conclusions ........................................................................................... 147 6. Catalytic urea decomposition ..................................................................... 148 6 Summary 6.1. Symbols .................................................................................................. 148 6.2. Introduction ........................................................................................... 149 6.3. Experimental ........................................................................................
Load more

Recommended publications
  • This Item Was Submitted to Loughborough University
    This item was submitted to Loughborough University as an MPhil thesis by the author and is made available in the Institutional Repository (https://dspace.lboro.ac.uk/) under the following Creative Commons Licence conditions. For the full text of this licence, please go to: http://creativecommons.org/licenses/by-nc-nd/2.5/ LOUGHBOROUGH UNIVERSITY OF TECHNOLOGY LIBRARY AUTHOR/FILING TITLE . -------------~§'~£~~~-~-;::r------_...: __________ i , ----------------!.------------------------ -- ----- - .....- , ACCESSION/COPY NO. --------------___ _L~~~~~/~~-----~- _____ ______ _ VOL. NO. CLASS MARK ISO C YA N I C ACID B Y D. J. BEL SON N .rkl ' A'~OCIORAL THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR , . ." , THE AWARD OF ~,_~,.' , ~ kf\S-r.. tt ; ~eCTeR OF PHILOSOPHY OF THE LOUGHBOROUGH UNIVERSITY OF TECHNOLOGY - 1981\ SUPERVISOR: DRI A, N, STRACHAN DEPARTMENT OF CHEM I STRY © BY D. J. BELSON J 1981. ..... ~- ~~c. \0) 'to 'b/O"2- .-'-' , C O,N TEN T S Chapter 1 Intr6duction .. 1 2 Preparation and storage of isocyanic acid.­ 3 3 Physical properties and structure of isocyanic acid. 11 4 Methods of analysis for isocyanic acid. 17 5 The polymerisation of isocyanic acid. 21 6 Pyrolysis and photolysis of isocyanicacid. 34 7 Reactions in water. 36 8: Reaction 'with alcohols. 48 9 Reactions with ammonia and amines. 52 10 Other addition reactions across th'e N=C double bond. 57· 11 Addition of isocyanic acid to unsaturated molecules. 65 12 Summary and conclUsions. 69 Acknowledgements. 82 Ref erenc es. 83 Figures Opposite Page 1 Van't Hoff equation plot for the gas- 23 phase depolymerisation of cyanuric acid. 2 Values of pKfor isocyanic acid 37 dissociation~;'- plotted against temperature.
    [Show full text]
  • ) (51) International Patent Classification: A01N 43/58
    ) ( 0 (51) International Patent Classification: Declarations under Rule 4.17: A01N 43/58 (2006.01) A01P 15/00 (2006.01) — as to applicant's entitlement to apply for and be granted a (21) International Application Number: patent (Rule 4.17(H)) PCT/EP20 19/055007 — of inventorship (Rule 4.17(iv)) (22) International Filing Date: Published: 28 February 2019 (28.02.2019) — with international search report (Art. 21(3)) (25) Filing Language: English (26) Publication Language: English (30) Priority Data: 18159322.9 28 February 2018 (28.02.2018) EP (71) Applicant: BASF SE [DE/DE]; Carl-Bosch-Str. 38, 67056 Ludwigshafen am Rhein (DE). (72) Inventors: NESVADBA, Peter; Klybeckstrasse 141, 4002 Basel (CH). CUNNINGHAM, Allan Francis; Klybeck¬ strasse 141, 4002 Basel (CH). NAVE, Barbara; Speyerer Strasse 2, 67 117 Limburgerhof (DE). WALLQUIST, Olof; Klybeckstrasse 141, 4002 Basel (CH). WISSEMEIER, Alexander; Speyerer Strasse 2, 671 17 Limburgerhof (DE). HINDALEKAR, Shirang; 1st Floor, VIBGYOR Towers, Plot C62, 40005 1 Mumbai (IN). POTHI, Tejas; G Block, Bandra Kurla Complex, 40005 1 Mumbai (IN). (74) Agent: MAIWALD PATENTANWALTS- UND RECHTSANWALTSGESELLSCHAFT MBH; Eva Dbrner, Postfach 33 05 23, 80065 Mtinchen (DE). (81) Designated States (unless otherwise indicated, for every kind of national protection available) : AE, AG, AL, AM, AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DJ, DK, DM, DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, HN, HR, HU, ID, IL, IN, IR, IS, JO, JP, KE, KG, KH, KN, KP, KR, KW, KZ, LA, LC, LK, LR, LS, LU, LY, MA, MD, ME, MG, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, NZ, OM, PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, RW, SA, SC, SD, SE, SG, SK, SL, SM, ST, SV, SY, TH, TJ, TM, TN, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW.
    [Show full text]
  • Thermodynamics and Reaction Mechanism of Urea Decomposition† Cite This: Phys
    PCCP View Article Online PAPER View Journal | View Issue Thermodynamics and reaction mechanism of urea decomposition† Cite this: Phys. Chem. Chem. Phys., 2019, 21,16785 a b b b Steffen Tischer, * Marion Bo¨rnhorst, Jonas Amsler, Gu¨nter Schoch and Olaf Deutschmann ab The selective catalytic reduction technique for automotive applications depends on ammonia production from a urea–water solution via thermolysis and hydrolysis. In this process, undesired liquid and solid by-products are formed in the exhaust pipe. The formation and decomposition of these Received 18th March 2019, by-products have been studied by thermogravimetric analysis and differential scanning calorimetry. Accepted 5th July 2019 A new reaction scheme is proposed that emphasizes the role of thermodynamic equilibrium of the DOI: 10.1039/c9cp01529a reactants in liquid and solid phases. Thermodynamic data for triuret have been refined. The observed phenomenon of liquefaction and re-solidification of biuret in the temperature range of 193–230 1Cis rsc.li/pccp explained by formation of a eutectic mixture with urea. Creative Commons Attribution-NonCommercial 3.0 Unported Licence. 1 Introduction and ammonium ISE (ion-selective electrode) measurements. Concluding from experimental results and literature data, 23 Air pollution by nitrogen oxides from Diesel engines is a major possible reactions including urea and its by-products biuret, problem concerning the environment and society. Therefore, cyanuric acid, ammelide, ammeline and melamine are presented. governments follow the need to regulate emissions by law (e.g., Further, cyanate and cyanurate salts and cyanamide are 715/2007/EG, ‘‘Euro 5 and Euro 6’’).1 The favored method to proposed as possible intermediates of high temperature urea reduce nitrogen oxides is selective catalytic reduction (SCR) decomposition.
    [Show full text]
  • United States Patent Office E
    Unitede States- Patent- Office 3,845,059E. 1. 2 The reaction of biuret with diethanolamine to form PREPARATION OF N,N'-DIETHANOL3,845,059 PIPERAZINE N,N'-diethanol piperazine can be illustrated as follows: Alvin F. Beale, Jr., Lake Jackson, Tex., assignor to The Dow Chemical Company, Midland, Mich. 2(HOCH)NH -- NH2CONHCONH --> No Drawing. Filed June 19, 1972, Ser. No. 264,704 5 CHO Int, C. C07d51/70 U.S. C. 260-268. SY 8 Claims /N al-woman-mamm CH, CH, ABSTRACT OF THE DISCLOSURE + 2CO. 1 + 8NHat Diethanolamine is reacted with urea or a urea pyrol- lo Y yzate (e.g. biuret, triuret, or cyanuric acid) to form N,N'-diethanol piperazine. The following chart illustrates the balanced stoichiom BACKGROUND OF THE INVENTION la etry for reacting diethanolamine with urea, biuret, triuret, N,N'-diethanol piperazine has been previously prepared and cyanuric acid. Reaction products Moles of Empirical Moles N,N'- Moles of formula of of diethanol Moles Moles (HOCH)NH Name of reactant reactant reactant piperazine of Co2 of NH3 2---------------------- Urea------------------------ CHNO 2 2 4. 2- ---. Biuret---. C2HNO2 2 3 6-- --- Triuret.----- ... C3HNO3 2 3. 6 8 6.----- ... Cyanuric aci - C3H3NO3 2 3. 6 6 by the condensation of piperazine with ethylene chloro- The reaction has been found to be specific for dieth hydrin as reported in J. Am. Chem. Soc., Vol. 55, p. 3823 anolamine since analogous dialkanolamines do not give (1933). The compound has been reported to have phar- corresponding dialkanol-substituted cyclic structures con macological properties as an anesthetic or sedative in 30 taining nitrogens within a carbon ring.
    [Show full text]
  • United States Patent (19) 11 Patent Number: 4,822,624 Young (45) Date of Patent: Apr
    United States Patent (19) 11 Patent Number: 4,822,624 Young (45) Date of Patent: Apr. 18, 1989 54 PRESERVATIVE FOR HARVESTED CROPS 4,033,747 7/1977 Young ................................... 426/69 (75) Inventor: Donald C. Young, Fullerton, Calif. 4,426,396 l/1984 Young .... ... 426/69 73 Assignee: Union Oil Company of California, FOREIGN PATENT DOCUMENTS Los Angeles, Calif. 117171 1/1976 German Democratic Rep. ... 426/69 Appl. No.: 1191470 5/1970 United Kingdom.................. 426/69 (21) 79,347 Primary Examiner-R. B. Penland 22 Filed: Jul. 30, 1987 Attorney, Agent, or Firm-Michael H. Laird; G. Wirzbicki Related U.S. Application Data (57) ABSTRACT 60 Continuation of Ser. No. 568,067, Jan. 4, 1984, aban doned, which is a division of Ser. No. 272,687, Jun. 11, The growth of microorganisms in stored crops, and 1981, Pat. No. 4,426,396. especially in animal feedstuffs, is inhibited by the appli (51) Int. C.'................................................ A23K 1/22 cation of a preservative composition which comprises (52) U.S. C. ........................................ 426/53; 426/69; ammonia, urease enzyme urea and/or urea polymers in 426/332; 426/532; 426/623; 426/630; 426/636; . a fluid medium. Urea polymers which are useful include 426/807 biuret, triuret, cyanuric acid, urea cyanurate and other (58) Field of Search ................... 426/53, 69,332, 532, compounds which decompose to form ammonia. The 426/623, 630, 807, 636 effect of treatment with the preservative composition is to provide an immediate microorganism-inhibiting am 56) References Cited monia level, which, due to delayed decomposition of U.S. PATENT DOCUMENTS the urea and urea polymers, is sustained to some signifi 1,702,735 2/1929 Legendre ...........................
    [Show full text]
  • Applied As Nitrogen Slow-Release Fertilizer
    Uncorretced Proof Facile Synthesis of Poly(Carbonyl Urea) Oligomer (Pcuo) from Urea and Dipropyl Carbonate (Dprc) Applied as Nitrogen Slow-Release Fertilizer 1,2JIANCHAO CHEN, 2YAQING LIU*, 1HONGFANG JIU, 2PEIHUA ZHAO AND 2FUTIAN ZHU 1 Department of Chemistry, School of Science, North University of China, Taiyuan 030051, P. R. China 2 Research Center for Engineering Technology of Polymeric Composites of Shanxi Province, North University of China, Taiyuan 030051, P. R. China. * [email protected] (Received on 19th September 2011, accepted in revised form 15th February 2012) Summary: A novel slow-release nitrogen fertilizer poly(carbonyl urea)oligomer (PCUO) was prepared by the condensation polymerization of urea and dipropyl carbonate (DPrC) at normal pressure, in which anhydrous potassium carbonate was as a catalyst. The oligomer was characterized by FT-IR, 1H- NMR, and 13C-NMR spectroscopy, which showed that the number average degree of PCUO was 1 to 5. The effects of the molar ratio of urea to DPrC, reaction time as well as the temperature on the yields were investigated and optimized. In addition, the slow-release behaviour of PCUO was evaluated in distilled water and the results showed that the product with good slow-release properties could be expected to have wide potential applications in modern agriculture and horticulture. Introduction The consumption of synthetic nitrogen methods for poly(carbonyl urea)oligomer have some fertilizer in agriculture has increased over the past drawbacks: the raw materials (e.g. sulfurisocyanatidic several decades, and it might continue to rise in order chloride, phosgene) and by-products (e.g. to meet the food demand of the growing global chlorinegas, hydrogen chloride and so forth) were population [1].
    [Show full text]
  • United States Patent 0 ICC Patented May 23, 1967
    1 3,321,603 United States Patent 0 ICC Patented May 23, 1967 1 2 increases so that the degree of e?'iciency of the cooler 3,321,603 decreases progressively. Since it is necessary to clean the RECOVERY OF UREA FROM OFF-GASES FROM heat exchange surfaces periodically from deposited urea, THE SYNTHESIS OF MELAMlNE FROM UREA IN THE GAS PHASE WHICH HAVE BEEN BREED for example by fusion, at least two condensers are re FROM MELAMINE quired for continuous operation. Guenther Hamprecht, Limburgerhof, Pfalz, Hermann It is an object of the present invention to provide a Dieter Fromm, Ludwigshafen (Rhine), Matthias simple and advantageous process for the recovery of urea Schwarzmann, Limhurgerhoi’, Pfalz, and Ludwig Vogei, from the off-gases from the synthesis of melamine from Frankenthal, Pfalz, Germany, assignors to Badische urea carried out in the gas phase and in the presence Anilin- & Soda-Fahrik Aktiengesellschaft, Ludwigshafen 10 of catalysts, said off-gas being substantially freed from (Rhine), Germany its melamine content by fractional condensation at 150° No Drawing. Filed Mar. 23, 1965, Ser. No. 442,176 Claims priority, application Germany, Mar. 28, 1964, to 200° C., preferably 170° to 190° C., wherein the said 76 110 incrustation is avoided. This object is achieved by bring 10 Claims. (Cl. 250-555) ing the off-gas into intimate contact with a melt of urea 15 or a melt of a mixture of urea and its thermal decomposi The present invention relates to a process for the treat tion products whose temperature is kept only slightly above ment of off-gas from the synthesis of melamine, such as its melting point.
    [Show full text]
  • Studies of Pf Resole / Isocyanate Hybrid Adhesives
    STUDIES OF PF RESOLE / ISOCYANATE HYBRID ADHESIVES by Jun Zheng A Dissertation submitted to the Faculty of Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Wood Science and Forest Products Approved by: Dr. Charles E. Frazier Chairman Dr. Frederick A. Kamke Dr. Wolfgang G. Glasser Dr. Richard F. Helm Dr. Garth L. Wilkes December 17, 2002 Blacksburg, Virginia Keywords: phenol-formaldehyde, isocyanate, adhesives, solid-state NMR, fracture testing, spectral decomposition, urethane, weathering, wood adhesion Copyright 2002, Jun Zheng STUDIES OF PF RESOLE / ISOCYANATE HYBRID ADHESIVES by Jun Zheng Charles E. Frazier, Chairman Wood Science and Forest Products ABSTRACT Phenol-formaldehyde (PF) resole and polymeric diphenylmethane diisocyanate (PMDI) are two commonly used exterior thermosetting adhesives in the wood-based composites industry. There is an interest in combining these two adhesives in order to benefit from their positive attributes while also neutralizing some of the negative ones. Although this novel adhesive system has been reportedly utilized in some limited cases, a fundamental understanding is lacking. This research serves this purpose by investigating some of the important aspects of this novel adhesive system. The adhesive rheological and viscometric properties were investigated with an advanced rheometer. The resole/PMDI blends exhibited non-Newtonian flow behavior. The blend viscosity and stability were dependent on the blend ratio, mixing rate and time. The adhesive penetration into wood was found to be dependent on the blend ratio and correlated with the blend viscosity. By using dynamic mechanical analysis, the blend cure speed was found to increase with the PMDI content.
    [Show full text]
  • Food Fraud in Nigeria: Challenges, Risks and Solutions
    Technological University Dublin ARROW@TU Dublin School of Food Science and Environmental Theses Health 2020 Food Fraud in Nigeria: Challenges, Risks and Solutions Joy Ewomazino Opia Technological University Dublin Follow this and additional works at: https://arrow.tudublin.ie/sfehthes Part of the Computer Sciences Commons Recommended Citation Opia, J. E. (2020). Food fraud in NIgeria: challenges, risks and solutions. Masters dissertation. Technological University Dublin. doi:10.21427/nm91-rk58 This Dissertation is brought to you for free and open access by the School of Food Science and Environmental Health at ARROW@TU Dublin. It has been accepted for inclusion in Theses by an authorized administrator of ARROW@TU Dublin. For more information, please contact [email protected], [email protected]. This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 4.0 License Food Fraud in Nigeria: Challenges, Risks and Solutions Joy Ewomazino Opia Msc. Food Safety Management Submitted to Technological University Dublin, Cathal Brugha Street, in partial fulfilment of the requirements of the Degree of Science (Food Safety Management, DT9437) Supervisor: Christine O’Connor School of Food Science and Environmental Health College of Sciences and health Technological University Dublin January 2020 1 ABSTRACT Food fraud is one of the most urgent and active food research and regulatory areas. It is an evolving problem in Nigeria that has led to the deaths of many people especially the vunerable groups that includes mostly children, the elderly and immunocomprised persons. Therefore the aim of this study is to investigate the current challenges of food fraud in Nigeria, identify the risks it poses on the health and wellbeing of Nigerians and propose measures to tackle food fraud at local and international levels by regulatory and government agencies.
    [Show full text]
  • Pharmaceutical Industry Guidance on Preventing Melamine Contamination
    Pharmaceutical Industry Guidance on Preventing Melamine Contamination August 6, 2009 the U.S. FDA issued a Guidance for Industry - Pharmaceutical Components at Risk for Melamine Contamination . The events involving pet and livestock food products, and milk products for infants illustrate the potential for drug components to be contaminated with melamine. This guidance says that certain pharmaceutical ingredients used in the manufacture or preparation of drug products are recommended to be screened for melamine. Hence, it is important for drug manufacturers to assure that no component used in the manufacture of any drug is con titdithliFDAtam ina ted w ith me lam ine. FDA recommen dthtds th at compoun d ers w h o use a t -r is k components in drugs ensure proper testing. The guidance for pharmaceuticals recommends the use of FDA-published methods based on equipment generally available to pharmaceutical manufacturers or contract testing labs. The test method used should be suitable to assay melamine contamination down to at least 2.5 parts per million (ppm). Recommended methods are based on liquid chromatography triple quadrupole tandem mass spectrometry (LC-MS/MS) or gas chromatography/mass spectrometry (GC-MS). The LC MS/MS method is based on HILIC and also urge the need to prevent melamine degradation during sample handling, (see FDA methods). The compounds at risk may be, but are not limited to: Adenine Albumin AiAmino ac iddidfid s der ive d from case in prote i n hy dro l ysates Ammon ium sa l ts Calcium pantothenate Caseinate or sodium caseinate Chlorophyllin copper complex sodium Colloidal oatmeal Copovidone Crospovidone Dihydroxyaluminum aminoacetate Gelatin Glucagon Guar gum Hyaluronidase Imidurea Lactose Melphalan Pov id one Pov id one- Io di ne Protamine sulfate Protein hydrolysate (powder) for injection Taurine Thioguanine Urea Wheat bran Zein This list was based on the FDA Inactive Ingredient Database (IID) , and is not considered to be exhaustive.
    [Show full text]
  • United States Patent (19) 11) 4,430,505 Heitkämper Et Al
    United States Patent (19) 11) 4,430,505 Heitkämper et al. (45) Feb. 7, 1984 (54) PROCESS FOR THE PREPARATION OF (56) References Cited N.O-DISUBSTITUTED URETHANES U.S. PATENT DOCUMENTS USEFUL FOR THE PREPARATION OF 2,409,712 10/1946 Schweitzer ... ... 260/453 A ISOCYANATES 2,806,051 9/1957 Brockway...... ... 560/24 75 Inventors: Peter Heitkämper, Dormagen; Klaus 3,627,813 12/1971 Abbate et al. ........................ 560/25 König, Leverkusen; Kurt Findeisen, 4,178,455 12/1979 Hirai et al. ............................ 560/24 Odenthal; Rudolf Fauss, Cologne; 4,388,238 6/1983 Heitkamper et al. ............. 560/22 X Rudolf Sundermann, Leverkusen, all of Fed. Rep. of Germany OTHER PUBLICATIONS 73) Assignee: Bayer Aktiengesellschaft, Adams et al., Chemical Reviews (1965) vol. 65, Leverkusen, Fed. Rep. of Germany 567-572. Primary Examiner-Bernard Helfin (21) Appl. No.: 197,032 Attorney, Agent, or Firm-Gene Harsh; Joseph C. Gil; 22 Filed: Oct. 15, 1980 Lyndanne M. Whalen 30 Foreign Application Priority Data 57 ABSTRACT Oct. 27, 1979 IDE Fed. Rep. of Germany ....... 29.43551 A process for the preparation of N.O-disubstituted ure 51) int. C. ................ C07C 125/065; CO7C 125/073 thanes. Urea or polyurets, primary amines and alcohols (52) U.S. C. ................................... 560/24; 260/465.4; are reacted at 120-350° C. in the presence of N-sub 260/465 D; 260/404; 260/239 E; 260/938; stituted urethanes and/or N-mono- or N,N'-disub 560/22; 560/25; 560/27; 560/28; 560/29; stituted ureas or polyureas. In a preferred embodiment, 560/30; 560/31; 560/32; 560/115; 560/145; the reactants further include catalysts known to be use 560/157; 560/158; 560/160; 560/161; 544/164; ful in esterification of carboxylic acids.
    [Show full text]
  • Paul D. Capel Open-File Report 89-613 St. Paul, Minnesota 1989
    A BIBLIOGRAPHY OF ATRAZINE AND ITS SIMPLE DEGRADATION PRODUCTS IN THE ENVIRONMENT Paul D. Capel U.S. GEOLOGICAL SURVEY Open-File Report 89-613 St. Paul, Minnesota 1989 DEPARTMENT OF THE INTERIOR MANUEL LUJAN, JR., Secretary U.S. GEOLOGICAL SURVEY Dallas L. Peck, Director For additional information Copies of this report can be purchased write to: from: U.S. Geological Survey District Chief Books and Open-File Reports Section U.S. Geological Survey Federal Center, Building 41 702 Post Office Building Box 25425 St. Paul, Minnesota 55101 Denver, Colorado 80225 u CONTENTS Page Abstract..........................................................................................................................................^ 1 Introduction.................................................^ 1 References.................................................^ 5 Environmental Prroesses.................................................................^^ 6 Transformation Processes................................................................................................................ 6 Biodegradation/Biotransformation........................................................................................... 6 Hydrolysis/Chemical Reactions................................................................................................. 24 Photolysis ...................................... 32 Transfer Processes............................................................................................................................. 34 Volatilization........................................^^
    [Show full text]