DOCSLIB.ORG

The Catalytic Oxidation of Benzene

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Catalytic Oxidation of Benzene THE CATALYTIC OXIDATION OF BENZENE '10 Ivi.LEIC ANHYDRIDE, JORGE FERN1DO R$4IREZ SOLIS THESIS PRESENTED FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF EDINBURGH 1974 TO MY PARENTS MA. LUISA y FAUSTINO TO MY BROTHERS VICTOR MAITJEL y JOSE LUIS ACKNOWLEDGMENTS I am deeply indebted to Professor P.H. Calderbank for his continued help, interest and encouragement throughout the course of this work. My thanks are due to Dr. S. Elnashaie for his advice in the programming. I would also like to thank Mr. David Ketchin and his workshop staff for their invaluable help in the building and maintenance of the experimental apparatus, to Dr. G. Nag for proof-reading, and to Mrs Margaret Gall and Miss Susan Robson for typing the manuscript. I am indebted to Lena whose companionship and good spirit are great help through difficulties. Finally, but by no means least, to the Universjd Nacional AutOnoma de Mexico (UNAM) and Banco de Mxico for financial support which made possible the realization of this work. Contents Page Acknowledgements Preface 1 Suimnary 11 Introduction 1 CHAPTER 1. LITERATURE SURVEY, VAPOUR PHASE CATALYTIC OXIDATION OF BENZENE TO MALEIC ANHYDRIDE. 1.1) Genera]. 8 1.2) Reaction Models and Mechanism 12 1.3) Homogeneous - Hetrogeneous Interactions 38 1.14) Object of the Study 145 CHAPTER 2. EXPERIMENTAL APPARATUS AND PROCEDURES (I) 2.1) Catalyst Preparation 148 2.2) General Description of the Experimental Apparatus. 51 2.2.1) Delivery of Reactants. 53 2.2.2) The Reactors. 55 2.2.3) Analytical Equipment 62 2.3) Catalyst Life and Stability 66 2.14) Typical Experimental Schedule 66 2.14) Calibration 68 CHAPTER 3. EXPERIMENTAL RESULTS 3.1) Measurements 71 3.2) Preliminary Experiments 71 3.3) Detection of Heterogeneous - Homogeneous Interactions in the Overall Reaction. Discussion. 72 Chapter 3. Cont... Page 3.14) Detection of Heterogeneous - Homogeneous Interactions in the Maleic Anhydride Combustion. 80 3.5) Effect of Reactor Materials of Construction on the Selectivity of the Overall Reaction 81 3.6) Kinetics of Benzene Disappearance and Selectivities to Maleic Anhydride. 3.6.1) Introduction 88 3.6.2) Experiments in a 100 Catalyst Pellet Catalytic Bed. 90 3.6.3) Experiments in a 250 Catalyst Pellet Catalytic Bed. 90 3.6.14) Effect of Reactor Diameter on Selectivity. io5 3.6.5) The SCB Reactor, Kinetics of Benzene Disappearance. 109 3.7) Kinetics of Maleic Anhydride Combustion. 3.7.1) Introduction. 113 3.7.2) The Tubular Reactor, Kinetics of Maleic Anhydride Combustion. 113 3.7.3) The SCB Reactor, Kinetics of Maleic Lnhydride Combustion A) Oxidation of Maleic Anhydride in the Presence of Catalyst. 118 b) Oxidation of Maleic Anhydride in the Absence of Catalyst. 118 3.8) Discussion of Results A) The Catalyst 121 B) Incorporation of the Experimental Data in the Overall Scheme of Reaction. 122 14• CHAPTER CHARACTEP1SCS OF TIE CATALYST USED IN THE PILOT PINT. 14.1) Introduction. 130 14.2) Kinetics of Benzene Disappearance and Selectivities to Maleic Anhydride. 130 14.3) Maleic Anhydride Combustion. 132 14.14) Conclusions. 136 CHAPTER 5. EXPERIMENTAL APPARATUS AND pocuas (II) Page 5.1) The Reactor and Reactor Shell 139 5.2) The Fluidizing Air System. 1146 5.3) Delivery of Reactants. 1146 5:3.1) The Air System. 146 5.3.2) The Benzene System. 147 5.14) Control and Instrumentation. 1148 5.5) Analytical Equipment. 149 5.6) Typical Experimental Schedule. 1149 CHAPTER 6. A MATHEMATICAL MODEL OF THE FIXED BED CATALYTI C REACTOR. 6.1) Introduction. 153 6.2) A Steady State Mathiatics1 Model of the Fixed Bed Reactor. 156 6.2.1) Mass Transfer in Packed Beds. 159 6.2.2) Heat Transfer in Packed Beds. 160 6.2.3) Form of the Model and Simplifications Introduced. 1614 6.2.4) Method of Solution of the Mathematical Model. 171 CHAPTER f. EXPERIMENTS WITH AND MODELLING OF THE PILOT PLANT REACTOR. 7.1) Introduction. 175 7.2) Results of Experimental and Modelling Work. 175 CHAPTER 8. CONCLUSIONS AND SUGGESTIONS FOR FURTHER WORK. 227 Appendix A Chemicals. Catalyst Support. Rotameter Capacities. 236 Appendix B Experimental Results from Chapter 3. 238 Appendix C Experimental Results from Chapter 14. 256 Page Appendix D Calculation of Rate Velocity Constants for the SCB and Tabular reactors. 261 Appendix E Least Squares Calculation of Slopes of straight Lines. 263 Appendix F Experimental Axial Teirxtrature Profiles in the One and Two inch Diameter Non-Isothermal Reactors. 266 Appendix G Computer Listing Program for One-Dimensional Plug Flow Model. 269 Bibliography 234 Nomenclature 295 Figures Figure Page 1.1 Activation Energy of the Isotopic Exchange of Oxygen and Selectivity in the Oxidation of Benzene and Butene to Maleic Acid. 37 2.1 Flow Diagram of the Experimental Apparatus 52 2.2 Aluminium Tubular Reactor Used in the Experiments at Isothermal Conditions. 56 2.3A 5GB Reactor and Stirrer Drive Unit. 58 2.3B SCB Reactor. Detail of the Catalyst Basket. 2. 14A SCBR. Mixing Characteristics of Carberry's (153) Reactor. 61 2.14B Sc13R. Mixing Characteristics of Brisk's (152) Reactor. Ci 2.5 Schematic Diagram of the Hot Sampling Valve. 63 2.6 Typical Chromatogram. 65 2.7 Benzene and Maleic Anhydride (FID) Calibration Curves. 69 3.3.1 Effect of Dilution and Free Space After the Bed., Reactor Arrangements. 75 3.3.2 Effect of Dilution and Free Space After the Bed on MA-A. Production. 75 3.3.3 Effect of Packing and Free Space After the Bed on Benzene Converted. 77 3.14.1 MM Combustion in Empty Reactors (Aluminium, Titanium, Stainless Steel and Glass). 82 3.5.1 Aluminium Reactor, Product Distribution with Temperature.- 83 3.5.2 Titanium Reactor, Product Distribution with Temperature. 84 3.5.3 Stainless Steel Reactor, Product Distribution with Temperature. 85 3.5.14 Effect of Reactor Materials of Construction on Selectivity to MAA. 86 3.5.5 Benzene Disappearance, Arrhenius Plots using Different Reactors but same Catalyst. 87 3.6.1 Short Bed Reactor (100 Catalyst Pellet Bed), XB vs (w/F). 91 3.6.2 Short Bed Reactor (100 Catalyst Pellet Bed), Product Distribution at 1475°C. 92 3.6.3 Short Bed Reactor (100 Catalyst Pellet Bed), Product Distribution at 500°C. 93 Short Bed Reactor (100 Catalyst Pellet Bed), 3.6.14 0 Selectivity vs Benzene Converted at 500 C. 93 3.6.5 Benzene Conversion vs Space Velocity (W/F), (250 Catalyst Pellet Bed). 95 3.6.6 M-AA. Production vs Space Velocity (250 Catalyst Pellet Bed). 9' 3.6.7 Overall Reaction (250 Cata1st Pellet Bed), Product Distributicia at 1400 C. 91 3.6.8 Overall Reaction (250 Catalst Pellet Bed), Product Distribution at 1420 C. 98 3.6.9 Overall Reaction (250 Catalst Pellet Bed), Product Distribution at 14140 C. 99 3.6.10 Overall Reaction (250 Catalst Pellet Bed), Product Distribution at 1460 C. 100 3.6.11 Overall Reaction (250 Catalyst Pellet Bed), Product Distribution at 1480 and 500°C. 101 3.6.12 Benzene Disappearance, First Order Plot. 102 3.6.13 Benzene Disappearance, Order Plot from XB vs (W/F) curve at 14140°C. 103 3.6.114 9 Inch Diameter Reactor, Experimental Selectivities as a Function of Benzene Converted. io14 3.6.15 Benzene Disappearance, Arrhenius Plots and 1 inch Dia. Reactors). 107 3.6.16 544 Inch Diameter Reactor, Experimental Selectivities as a Function of Benzene Converted. 108 3.6.17 SCBR, Benzene Disappearance Order Plots. 11]. 3.6.18 Comparison Between Benzene Disappearance Rates in Tubular and SCJ3 Reactors. 112 3.7.1 Aluminium Tubular Reactor, MAA Combustion/Catalyst. 1114 3.7.2 Glass Tubular Reactor, MAA Combustion/Catalyst. 116 3.7.3 Glass Tubular Reactor, Arrhenius Plot for MAA Oxidation/Catalyst. 117 3.7.14 SCLR, Order Plots for MA Oxidation on Catalyst and on Empty Reactor. 119 3.7.5 ScBR, MAA Oxidation on Catalyst and on Empty Reactor. 120 3.8.11.B. Tubular Reactor, Experimental (A) and Predicted (B) Selectivities to IVIAA. 126 3.8.2 Arrhenius Plots for the Steps in the Overall Reaction Scheme. 127 3.8.3 Tubular Reactor, Experimental and Predicted Concentration Profiles for Benzene and Maleic Anhydride at 480 and 5000C. 128 14.1 Arrhenius Plots for Benzene Disappearance and MAA Oxidation (Catalyst 6,s.s. Reactor). 133 14.2 Stainless Steel Tubular Reactor, Reaction Selectivity, vs ]3enzene Converted. 1314 14.3 Co/CO 2 Molar Ratio as a Function of Benzene Converted. 135 5.1 Pilot Plant Flow Diagram. 1141 5.2 The One Inch Diameter Reactor. 1142 5.3 The One Inch Diameter Reactor, Thermocouple Locations. 1142 5.14 The Reactor Shell. 1143 5.5 Heating Elements Arrangement. 11414 5.6 The Two Inch Diameter Reactor. 1145 6.2 Geometrical Interpretation (Predictor). 173 6.3 Geometrical Interpretation (Corrector). 173 7.1 One Inch Diameter Reactor, Difference etween Experimental and Predicted Axial Temperature Profiles (U = 95). 176 11 T.2 Experimental Radial Temperature Profiles in the Two inch Diameter Reactor. 178 7.3 Arrhenius Plots for the Benzene Disappearance Step on Active (green) and Deactivated (black) Catalyst Pellets. 185 7.4 Effect of Kinetic Parameters on Reaction Behaviour. 187 7.5 - 7.14 One Inch Diameter Reactor, Experimental and ?Best Fit? Axial Tem-perature Profiles 194-203 7.15 - 7.23 Two Inch Diameter Reactor, Experimental and 'Best Fit' Axial Temperature Profiles. 2O4-212 7.21 Predicted and 'Best Fit' Overall Heat Transfer Coefficients for the One and. Two Inch Diameter Reactors. 219 7.25 Estimated Peclet Numbers for the One and Two Inch Diameter Reactors as a Function of Mass Velocity. 224 Tables Table Page I Breakdown of Maleic Anhydride usage in the U.S.A.
Load more

Recommended publications
  • Succinic Acid
    ENVIRONMENTAL FACTSHEET: SUCCINIC ACID PRODUCT INFORMATION Succinic acid (COOH(CH2)2COOH) is a carboxylic acid used in food (as an acidulant), pharmaceutical (as an excipient), personal care (soaps) and chemical (pesticides, dyes and lacquers) industries. Bio-based succinic acid is seen as an important platform chemical for the production of biodegradable plastics and as a substitute of several chemicals (such as adipic acid) [1]. Lignocellulosic Crops and Starch Crops Sugar Crops Today succinic acid is mainly produced Type of Type Biomass Residues from fossil resources through maleic acid hydrogenation. It can also be produced through fermentation of sugars. In that Cultivation and Harvesting case, in addition to succinic acid, other Biomass carboxylic acids (such as lactic acid, formic Production acid, propionic acid) and alcohols (such as ethanol) are also obtained. The production Starch Sugar Pretreatment Extraction & Extraction & ratios of these by-product compounds Separation Separation depend on the microorganism strain used and on the operation conditions. Several Hemicellulose Food Food Feed companies and industrial consortiums Lignin Cellulose Starch Feed Saccharose started bio-based production of succinic acid at demonstration scale (up to 70 ktonnes/year of full capacity, per Hydrolysis production plant [2]). Two strategies are being used for succinic acid fermentation [1]: (1) Use of bacteria strains, isolated Glucose from rumen. This strains are excellent Biomass Conversion Biomass natural succinic acid producers and their yields can be improved, though metabolic engineering; (2) Use of well-known Fermentation industrial microorganisms (such as Escherichia coli or Saccharomyces cervisiae) and modify their minor succinic acid production capability into high yields Succinic Acid through metabolic engineering.
    [Show full text]
  • APPENDIX G Acid Dissociation Constants
    harxxxxx_App-G.qxd 3/8/10 1:34 PM Page AP11 APPENDIX G Acid Dissociation Constants §␮ ϭ 0.1 M 0 ؍ (Ionic strength (␮ † ‡ † Name Structure* pKa Ka pKa ϫ Ϫ5 Acetic acid CH3CO2H 4.756 1.75 10 4.56 (ethanoic acid) N ϩ H3 ϫ Ϫ3 Alanine CHCH3 2.344 (CO2H) 4.53 10 2.33 ϫ Ϫ10 9.868 (NH3) 1.36 10 9.71 CO2H ϩ Ϫ5 Aminobenzene NH3 4.601 2.51 ϫ 10 4.64 (aniline) ϪO SNϩ Ϫ4 4-Aminobenzenesulfonic acid 3 H3 3.232 5.86 ϫ 10 3.01 (sulfanilic acid) ϩ NH3 ϫ Ϫ3 2-Aminobenzoic acid 2.08 (CO2H) 8.3 10 2.01 ϫ Ϫ5 (anthranilic acid) 4.96 (NH3) 1.10 10 4.78 CO2H ϩ 2-Aminoethanethiol HSCH2CH2NH3 —— 8.21 (SH) (2-mercaptoethylamine) —— 10.73 (NH3) ϩ ϫ Ϫ10 2-Aminoethanol HOCH2CH2NH3 9.498 3.18 10 9.52 (ethanolamine) O H ϫ Ϫ5 4.70 (NH3) (20°) 2.0 10 4.74 2-Aminophenol Ϫ 9.97 (OH) (20°) 1.05 ϫ 10 10 9.87 ϩ NH3 ϩ ϫ Ϫ10 Ammonia NH4 9.245 5.69 10 9.26 N ϩ H3 N ϩ H2 ϫ Ϫ2 1.823 (CO2H) 1.50 10 2.03 CHCH CH CH NHC ϫ Ϫ9 Arginine 2 2 2 8.991 (NH3) 1.02 10 9.00 NH —— (NH2) —— (12.1) CO2H 2 O Ϫ 2.24 5.8 ϫ 10 3 2.15 Ϫ Arsenic acid HO As OH 6.96 1.10 ϫ 10 7 6.65 Ϫ (hydrogen arsenate) (11.50) 3.2 ϫ 10 12 (11.18) OH ϫ Ϫ10 Arsenious acid As(OH)3 9.29 5.1 10 9.14 (hydrogen arsenite) N ϩ O H3 Asparagine CHCH2CNH2 —— —— 2.16 (CO2H) —— —— 8.73 (NH3) CO2H *Each acid is written in its protonated form.
    [Show full text]
  • Maleic Anhydride
    Product Stewardship Summary Maleic anhydride General Statement Maleic anhydride (MAN) is an organic chemical intermediate for the manufacture of numerous products including unsaturated polyester resins (UPR), MAN-based copolymers, lube oil additives, alkyl succinic anhydrides (ASA), malic acid, fumaric acid and various agricultural chemicals. UPR’s are used in boats, automobiles, buildings, piping, and electrical goods. MAN-based copolymers consist of a wide variety of copolymers with diverse applications including compatibilizers and coupling agents with polyolefins and as thickeners, dispersants and stabilizing agents in consumer products such as cosmetics and toiletries. Lube oil additives synthesized from maleic anhydride are used to prolong oil change intervals and improve engine efficiency. ASA’s are used in a variety of applications including paper sizing, detergents, leather treatment and food products. Malic acid is primarily used as an additive to food and beverages to control pH and enhance flavors. Fumaric acid uses include paper sizing, food acidulant and UPR manufacture. Agricultural chemicals from maleic anhydride include pesticides, herbicides and growth regulators. Maleic anhydride rapidly forms maleic acid when in contact with water. This acid is an irritant and skin sensitizer. Consumer exposure to maleic anhydride is uncommon, and worker exposure is controlled by protective equipment and ventilation. Chemical Identity Name: Maleic Anhydride Brand Names: Sold as such, and incorporated into unsaturated polyester resins and food additive products Chemical name (IUPAC): furan-2,5-dione CAS number(s): 108-31-6 EC number: 203-571-6 Molecular formula: C4H2O3 Structure: Uses and Applications Ashland produces maleic anhydride in the USA. Ashland uses maleic anhydride to produce unsaturated polyester resins and food additive products.
    [Show full text]
  • 3.2 N-Butane to Maleic Anhydride
    Alma Mater Studiorum – Università di Bologna DOTTORATO DI RICERCA IN Chimica Ciclo XXVII Settore Concorsuale di afferenza: 03/C2 Settore Scientifico disciplinare: CHIM/04 THE SYNTHESIS OF MALEIC ANHYDRIDE: STUDY OF A NEW PROCESS AND IMPROVEMENT OF THE INDUSTRIAL CATALYST Presentata da: Giulia Pavarelli Coordinatore Dottorato Relatore Prof. Aldo Roda prof. Fabrizio Cavani Esame finale anno 2015 Summary Summary 1 Aim of work ..............................................................................5 2 Introduction ...............................................................................7 2.1 Maleic anhydride .............................................................................. 7 2.2 Maleic anhydride production .......................................................... 10 2.3 Commercial Maleic Anhydride Technologies ............................... 13 2.3.1 Fixed bed .................................................................................. 14 2.3.2 Fluidized bed ............................................................................ 15 2.3.3 Transported bed ........................................................................ 16 2.4 Vanadyl pyrophosphate catalyst ..................................................... 17 2.4.1 Synthesis of the precursor VOHPO4·0.5H2O........................... 18 2.4.2 Thermal treatment of the precursor VOHPO4·0.5H2O: mechanism of transformation of VHP to VPP ..................................... 20 2.4.3 Activation of (VO)2P2O7 catalyst ............................................
    [Show full text]
  • Dissociation Constants of Organic Acids and Bases
    DISSOCIATION CONSTANTS OF ORGANIC ACIDS AND BASES This table lists the dissociation (ionization) constants of over pKa + pKb = pKwater = 14.00 (at 25°C) 1070 organic acids, bases, and amphoteric compounds. All data apply to dilute aqueous solutions and are presented as values of Compounds are listed by molecular formula in Hill order. pKa, which is defined as the negative of the logarithm of the equi- librium constant K for the reaction a References HA H+ + A- 1. Perrin, D. D., Dissociation Constants of Organic Bases in Aqueous i.e., Solution, Butterworths, London, 1965; Supplement, 1972. 2. Serjeant, E. P., and Dempsey, B., Ionization Constants of Organic Acids + - Ka = [H ][A ]/[HA] in Aqueous Solution, Pergamon, Oxford, 1979. 3. Albert, A., “Ionization Constants of Heterocyclic Substances”, in where [H+], etc. represent the concentrations of the respective Katritzky, A. R., Ed., Physical Methods in Heterocyclic Chemistry, - species in mol/L. It follows that pKa = pH + log[HA] – log[A ], so Academic Press, New York, 1963. 4. Sober, H.A., Ed., CRC Handbook of Biochemistry, CRC Press, Boca that a solution with 50% dissociation has pH equal to the pKa of the acid. Raton, FL, 1968. 5. Perrin, D. D., Dempsey, B., and Serjeant, E. P., pK Prediction for Data for bases are presented as pK values for the conjugate acid, a a Organic Acids and Bases, Chapman and Hall, London, 1981. i.e., for the reaction 6. Albert, A., and Serjeant, E. P., The Determination of Ionization + + Constants, Third Edition, Chapman and Hall, London, 1984. BH H + B 7. Budavari, S., Ed., The Merck Index, Twelth Edition, Merck & Co., Whitehouse Station, NJ, 1996.
    [Show full text]
  • Dl-MALIC ACID
    dl-MALIC ACID Prepared at the 57th JECFA (1999) and published in FNP 52 Add 9 (2001), superseding specifications prepared at the 53rd JECFA (1999), published in FNP 52 Add 7 (1999). ADI “not specified”, established at the 13th JECFA in 1969. SYNONYMS 2-Hydroxybutanedioic acid; INS No. 296 DEFINITION Chemical names dl-Malic acid, 2-Hydroxybutanedioic acid, Hydroxysuccinic acid C.A.S. number 617-48-1 Chemical formula C4H6O5 Structural formula Formula weight 134.09 Assay Not less than 99.0% DESCRIPTION White or nearly white crystalline powder or granules FUNCTIONAL USES Acidity regulator, flavouring agent (See ‘Flavouring agents’ monograph JECFA no. 619) CHARACTERISTICS IDENTIFICATION Solubility (Vol. 4) Very soluble in water; freely soluble in ethanol Melting range (Vol. 4) 127 - 132° Test for malate (Vol. 4) Passes test Test 5 ml of a 1 in 20 solution of the sample, neutralized with ammonia TS PURITY Sulfated ash (Vol. 4) Not more than 0.1% Test 2 g of the sample (Method I) Fumaric and maleic acid Not more than 1.0% of fumaric acid and not more than 0.05% of maleic acid See description under TESTS Lead (Vol. 4) Not more than 2 mg/kg Determine using an atomic absorption technique appropriate to the specified level. The selection of sample size and method of sample preparation may be based on the principles of the method described in Volume 4, “Instrumental Methods.” TESTS PURITY TESTS Fumaric and maleic acid Buffer solution A In a 1000-ml volumetric flask dissolve 74.5 g of potassium chloride in 500 ml of water, add 100 ml of concentrated hydrochloric acid, and dilute to volume with water.
    [Show full text]
  • Kinetics of the Reaction .,Of N-Ethylmalemide
    KINETICS OF THE REACTION .,OF N-ETHYLMALEMIDE WITH CYSTEINE AND SOME CONGENERS By PETAR A. MARTIC \·\ Bachelor of Science University _of Belgrade · Belgrade, Yugoslavia 1962 Submitted to the Faculty of the Graduate School of the Oklahoma State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May, 1966 O[<LAHOM,~ STATE UN!VERSITY LIBRARY JUN 10 1966 . ,.. ~··;-... ,, .... ...~,,···~, ... ,,..~.:·. ·•-l•····~··""'•,,•• • ,.. ,,•. , ....... -... r-\"::W KINETICS OF THE REACTION OF ~ N-ETHYLMALEIMIDE WITH CYSTEINE AND SOME CONGENERS Thesis Approved: ~ A~ Thesis Adviser Dean of the Graduate School 6101~-0 ACKNOWLEDGMENTS (1) I want to express my gratitude to·Professor George Gorin for his advice and supervision throughout my studies .. I also want to thank the National Institutes of Health for financial help and support in the form of a research assistantship . My gratitude is extended to my colleague·Mr .. Gavin Doughty. who performed the least~square analysis·with an IBM 1410 computer. iii TABLE OF.CONTENTS Chapter .· Page · I. INTRODUC'rI0N •. • • • • ' f 0 • 1 .. II. REVIEW OF PERTINENT LITERATURE. .3 •Mercapto Groups, in• Proteins. and. Enzymes.. • • • • . 3 Bibliography of Applications of theReactions•Between N­ ethylmaleimide (NEM) and Mercapto ,Groups· in·. Proteins and.Peptides •.•..••..••••.•••.••.• , . • 5 Additions of Mercaptans to· Double Bonds. • • • • • • • • 13 · Kinetics·of.Addition Reactions·of Mercaptans to·Carbon- Carbon Double·Bonds. • • . • • • • • • • . • • • • • • 18 III •. KINETICS OF THE REACTI0N OF N-ETHYLMALEIMIDE WITH,CYS~EINE AND SOME C0NGENERS (SUMMARY). 21 Materials. • , 22 ·Apparatus. 23 Procedure •.• 23 · Calculations • . 24 IV. APPENDIX •.•• 33 , Calculation of k by Least-Square ·Method. • • • • • 33 . Additit>nal Details, Concerning the Reaction .of Mercaptans with ~EM"."'" • • • • • • • • • ••. 35 \ l3IBLl©GRAPHY.
    [Show full text]
  • Metabolic Engineering for Fumaric and Malic Acids Production
    Metabolic Engineering for Fumaric and Malic Acids Production Dissertation Presented in Partial Fulfillment of the Requirement for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Baohua Zhang, M.S. Ohio State Biochemistry Program The Ohio State University 2012 Dissertation Committee: Professor Shang-Tian Yang, Advisor Professor Jeffrey Chalmers Professor Hua Wang Copyright by Baohua Zhang 2012 ABSTRACT Fumaric acid is a natural organic acid widely found in nature. With a chemical structure of two acid carbonyl groups and a trans-double bond, fumaric acid has extensive applications in the polymer industry, such as in the manufacture of polyesters, resins, plasticizers and miscellaneous applications including lubricating oils, inks, lacquers, styrenebutadiene rubber, etc. It is also used as acidulant in foods and beverages because of its nontoxic feature. Currently, fumaric acid is mainly produced via petrochemical processes with benzene or n-butane as the feedstock. However, with the increasing crude oil prices and concerns about the pollution problems caused by chemical synthesis, a sustainable, bio-based manufacturing process for fumaric acid production has attracted more interests in recent years. Rhizopus oryzae is a filamentous fungus that has been extensively studied for fumaric acid production. It produces fumaric acid from various carbon sources under aerobic conditions. Malic acid and ethanol are produced as byproducts, and the latter is accumulated mainly when oxygen is limited. Like most organic acid fermentations, the production of fumaric acid is limited by low productivity, yield and final concentration influenced by many factors including the microbial strain used and its morphology, medium composition, and neutralizing agents.
    [Show full text]
  • AP-42, CH 6.14: Maleic Anhydride
    6.14 Maleic Anhydride 6.14.1 General1 The dominant end use of maleic anhydride (MA) is in the production of unsaturated polyester resins. These laminating resins, which have high structural strength and good dielectric properties, have a variety of applications in automobile bodies, building panels, molded boats, chemical storage tanks, lightweight pipe, machinery housings, furniture, radar domes, luggage, and bathtubs. Other end products are fumaric acid, agricultural chemicals, alkyd resins, lubricants, copolymers, plastics, succinic acid, surface active agents, and more. In the United States, one plant uses only n-butane and another uses n-butane for 20 percent of its feedstock, but the primary raw material used in the production of MA is benzene. The MA industry is converting old benzene plants and building new plants to use n-butane. MA also is a byproduct of the production of phthalic anhydride. It is a solid at room temperature but is a liquid or gas during production. It is a strong irritant to skin, eyes, and mucous membranes of the upper respiratory system. The model MA plant, as described in this section, has a benzene-to-MA conversion rate of 94.5 percent, has a capacity of 22,700 megagrams (Mg) (25,000 tons) of MA produced per year, and runs 8000 hours per year. Because of a lack of data on the n-butane process, this discussion covers only the benzene oxidation process. 6.14.2 Process Description2 Maleic anhydride is produced by the controlled air oxidation of benzene, illustrated by the following chemical reaction: V2O5 2C6H6 +9O2 >2C4H2O3+H2O+ 4CO2 MoO3 Benzene Oxygen Catalyst Maleic Water Carbon > anhydride dioxide Vaporized benzene and air are mixed and heated before entering the tubular reactor.
    [Show full text]
  • The Dissociation Constants of the Carboxyl and Hydroxyl Groups in Some Insoluble and Sol-Forming Polysaccharides
    The dissociation constants of the carboxyl and hydroxyl groups in some insoluble and sol-forming polysaccharides By S. P. S a r i c a n d R. K. S c h o f i e l d Soil Physics Department, Rothamsted Experimental Station, Harpenden, Herts (i Communicated by B. A.Keen, F.R.S.—Received 26 October 1944) In order to establish the conditions under which the buffering of insoluble substance may most usefully be studied, suspensions of fibre cellulose, hemicellulose and xylan have been examined to determine the relationship between pH and the degree of dissociation of their carboxyl groups. The materials were suspended in normal potassium chloride solution, in order to confine local gradients of hydrion concentration to the immediate vicinity of each charged buffer group. Under these conditions the dissociation curves are all of the simple Henderson type with a common constant p K = 2*95 (n/100 hydrochloric acid in normal potassium chloride being taken as pH 2). Sols of arabic and pectic acid follow the same dissociation curve, showing that the dis­ sociation of the carboxyl groups is not necessarily influenced by the state of aggregation. Within the accuracy of these measurements, uronic and gluconic carboxyls have the same p K . The dissociation of pectic acid departs from the Henderson curve in the same general way as the dissociation curve of maleic acid differs from that of fumaric acid. It is suggested that some of the carboxyls in pectic acid are linked by hydrogen bridges. To a less extent such linkage may also occur in alginic acid below pH 3 when a gel is formed.
    [Show full text]
  • United States Patent (19) 11 Patent Number: 4,612,378 Bosshard Et Al
    United States Patent (19) 11 Patent Number: 4,612,378 Bosshard et al. (45) Date of Patent: Sep. 16, 1986 54) PROCESS FOR THE PREPARATION OF Primary Examiner-John Kight B-(BENZOTHIAZOLYLTHIO). AND Assistant Examiner-Garnette D. Draper B-(BENZIMIDAZOLYLTHIO)-CARBOXYIC Attorney, Agent, or Firm-Luther A. R. Hall ACDS 57 ABSTRACT (75) Inventors: Hans Bosshard, Basel; Hans Greuter, The reaction of 2-mercapto-benzothiazole or -benzimid Eiken, both of Switzerland azole with a 9-unsaturated carboxylic acids in a 73) Assignee: Ciba-Geigy Corporation, Ardsley, strongly acid reaction medium gives compounds of the N.Y. formula I (21) Appl. No.: 610,145 R I 22 Filed: May 14, 1984 R N R R2 (30) Foreign Application Priority Data N C-S-C-CH May 14, 1983 GB United Kingdom ................. 8313321 / X R3 COOH 51) Int. Cl............................................. C07D 277/70 R 52 U.S. Cl...... ... 548/170; 548/329 58 Field of Search ................................ 548/170, 329 R (56) References Cited in which X is sulfur or NH, each radical R indepen U.S. PATENT DOCUMENTS dently of one another is H, alkyl, halogenoalkyl, alkoxy, 2,725,364 11/1955 Dozzi .................................. 548/170 alkylthio, alkylsulfonyl, phenyl, alkylphenyl, phenylal 3,499,085 3/1970 Sasse et al. ... ... 548/329 kyl, cycloalkyl, halogen, NO2, CN, COOH, COOalkyl, 4,289,886 9/1981 D'Amico ............................. 548/170 OH or an amino or carbamyl group and R, R2 and R3 independently of one another are H, alkyl, halogenoal FOREIGN PATENT DOCUMENTS kyl, hydroxyalkyl, alkoxyalkyl, carboxyalkyl, carboxyl 0204-183 11/1983 Japan ................................... 548/170 or unsubstituted or substituted aryl or aralkyl, or Rand 149785 9/1962 U.S.S.R.
    [Show full text]
  • Transient Kinetics of N-Butane Oxidation to Maleic Anhydride Over a VPO Catalyst
    http://www.paper.edu.cn Transient Kinetics of n-Butane Oxidation to Maleic Anhydride over a VPO Catalyst Xiao-Feng Huang, Cheng-Yue Li, and Biao-Hua Chen The Key Laboratory of Science and Technology of Controllable Chemical Reactions, Ministry of Education, Beijing University of Chemical Technology, Beijng 100029, China P. L. Silveston Dept. of Chemical Engineering, University of Waterloo, Waterloo, Ontario, Canada Transient reaction kinetics is usually needed to model the reactor system operated under unsteady-state mode to impro®e the performance of the catalyst packed in such a reactor system and to match operating conditions of different reaction steps in this system. The transient reaction kinetics of n-butane oxidation to maleic anhydride o®er a commercial VPO catalyst was systematically studied, using online MSrGC measure- ments, transient response, and forced periodic operation methods. A simplified scheme with respect to the reaction network is proposed based on the pre®ious studies and the obser®ations in this work. Combining the results on the roles of lattice and adsorbed oxygen in the reaction process with the data obtained in transient response experiments, a transient kinetic model taking account of the oxygen storage and diffusion in the bulk-phase of the catalyst was introduced and its parameters were estimated. The model was examined by the transient response experimental data and time-a®erage concentra- tions of butane and maleic anhydride under forced unsteady-state operation. Introduction The selective catalytic oxidation of hydrocarbon is an im- were proposed based on a triangular reaction network portant reaction for producing oxygenates, mostly using com- ŽEscardino et al., 1973; Wohlfahrt et al., 1980; Buchanan and plex oxides of metals as catalyst and running according to the Sundaresan, 1986; Schneider et al., 1987; Sharma et al., 1991; redox mechanism.
    [Show full text]