DOCSLIB.ORG

BACTERIAL HYDROCARBON OXIDATION Davis

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
BACTERIAL HYDROCARBON OXIDATION Davis BACTERIAL HYDROCARBON OXIDATION I. OXIDATION OF n-HEXADECANE BY A GRAM-NEGATIVE COCCuS' JAMES E. STEWART,2 3R. E. KALLIO, D. P. STEVENSON, A. C. JONES, AND D. 0. SCHISSLER Department of Bacteriology, State University of Iowa, Iowa City, Iowa, and Shell Development Company, Emeryville, California Received for publication March 17, 1959 The pioneering work of Sohngen (1913) es- (Brown and Strawinski, 1958; Dworkin and tablished that a variety of aerobic microorganisms Foster, 1956). Many reports in the literature are capable of growing at the sole expense of indicate that fatty acids, aldehydes, or alcohols diverse paraffins. These findings have been have been recovered from cultures oxidizing extended and corroborated so often since then aliphatic paraffins (see Beerstecher, 1954, for that detailed documentation does not seem neces- complete citations). In no case, however, has a sary here, especially since the subject of microbial fatty acid (or other intermediate) been identi- hydrocarbon oxidation has been comprehensively fied which has a carbon skeleton identical to the and frequently reviewed (Beerstecher, 1954; alkane being oxidized, thus leaving in question Davis and Updegraff, 1954; ZoBell, 1950). the locus of the primary enzymatic attack on the Despite the extensive literature on the subject alkane molecule. of the mechanisms by which bacteria and other This paper summarizes preliminary findings of microorganisms attack hydrocarbons, the re- a study undertaken to investigate the mecha- actions have not been subjected to intensive nisms of microbial attack on aliphatic paraffins. experimental study. For example, an important goal in the establishment of a metabolic mecha- MATERIALS AND METHODS nism, namely, the isolation and identification A gram-negative coccus (designated as H.O.1 of an intermediate compound reasonably close during this study), with ability to utilize a wide to the substrate in terms of structure, has been variety of organic compounds for growth, was accomplished in the microbial oxidation of ali- isolated from hexadecane-mineral salts enrich- phatic hydrocarbons only three times; of these ments. The enrichments were incubated at room only one is alkane oxidation. Birch-Hirschfeld temperature on a gyratory shaker and after 7 (1932) detected the presence of acetaldehyde in days a transfer was made to fresh medium, fol- cultures of Mycobacterium lacticola growing at lowing which 6 serial transfers at 48-hr intervals the expense of acetylene. Bruyn (1954) isolated were made to flasks containing fresh mineral- and identified 1, 2-hexadecanediol in cultures of hexadecane medium. Pure cultures were ob- Candida lipolytica growing in a mineral salts- tained by streaking on mineral agar and in- hexadecene-1 medium. Finally, chemical evi- cubating in a paraffin atmosphere obtained by dence has been reported which strongly suggests adding 1.0 ml of sterile hexadecane to a circle of that methanol, formaldehyde, and formic acid filter paper previously inserted in the lid of the are produced from methane by Methanomonas petri plate. The detailed microbiological at- methanooxidans and Pseudomonas methanica tributes of all isolates from hexadecane as well as other hydrocarbon enrichments will be the ' This study was supported by a grant from the subject of a separate report. All isolates thus far Petroleum Research Fund administered by the have been gram-negative cocci. Strain H.O.1 was American Chemical Society. Grateful acknowl- chosen for study because of its profuse and edgement is hereby made to the donors of said homogenous growth on alkanes and its relatively fund. low rate. The 2 American Chemical Society, Petroleum Re- endogenous respiratory organism search Fund Predoctoral Fellow. is catalase positive and does not exhibit fat 3Present address: Technological Station, Fish- globules at any stage of growth. eries Research Board of Canada, Halifax, Nova Large scale cultures were set up with 1 L of Scotia. mineral medium in a 3-L Fernbach flask inocu- 441 442 STEWART, KALLIO, STEVENSON, JONES, AND SCHISSLER [VOL. 78 lated with 1 pexr cent of 48-hr growth of the or- gen analysis showed C = 79.48 per cent; H ganism on the s,,ame medium. Sterile hexadecane 13.28 per cent; and 0 = 7.24 per cent (by dif- was added at tble time of inoculation to provide ference). Phenolphthalein titration in ethanol a carbon source of 1 per cent (v/v). Cultures indicated that the substance was not an acid. were grown on Ea gyratory shaker at 250 rpm at The infrared spectrum of a carbon tetachloride room temperatu]re. soluti6n of the material showed ibsorption bands Titratable aciLdity, pH, and oxygen consump- at 3.42 and 3.51 p, characteristic of the C-H tion were determined by standard methods. stretch motion of -CH2-- or -OH. groups, Growth was diifficult to measure during the and at 6.83 ps characteristic of -CH,- bending course of an experiment because of the forma- motions. Additionally the material showed bands tion of stable emulsions of the hydrocarbon under at 5.74 p characteristic of carbonyl groups and the combined action of bacterial attack and con- another band at 8.53 p. The absorptivity of the stant agitation. 'The method finally adopted con- 5.74 p band was found to be 89 L per 100 g cm. sisted of transfeirring 6.5 ml of culture fluid to a In isopropyl alcohol, this band separated into pyrex centrifuge tube having a narrow tip gradu- two components of about equal intensity at 5.73 ated in hundredlths from 0.1 to 0.4 ml. Tubes p and 6.79 , a unique diignostic crcistic were centrifuged[ for 30 min at 1500 X G and of the ester structure (A. C. Jons, bed growth was reciorded as milliliters of cells per oem,. Taking the molal absorptivity of 6.5 ml. the 5.t4 band of esters (im CCl) to ble 450 L A WestinghouLse type LV mass spectrometer, per mol cm, the absorbance of the bacterial modified to have a nominal resolving power of oxidation intermediate corresponds to that of 1 in 350, with a heated inlet system was used to an ester with molecular weight equal to 500 t 50. record the mass spectra. The mass spectra were The nzwss spectrum showed a stront ion intensity scanned with coinstant ion accelerating potential at a position corresponding to a C, hydrocarbon by varying the mass analyzing field. The ion indicating the molecular weight of the material source temperatiure was about 200 C and 75 v to be.480 ± 14. The next strong intensities on ionizing electron:s were employed to generate the a descending mass scale were a set of three peaks ions. of mass to charge ratio 258, 257, and 256, and Other procedures used are outlined in Results a set of two at 225 and 224. In thse iets, those and Discussion. at 257 and 224 were much more intee.f16ma to charge ratios of these ions were Witively RESUFLT5 AND DISCUSSION identifid by the addition of an authentic sample Preliminary cibservation on earlier isolates of normal octadecane and recording of the mass szimilarj;1l1ll1al toUV TI(-0Ls.L.N111ALMAIUUIUCUVUhadl indioaf.wlUWCVthat.llULmlA1inDnir rL-vnro+AhblVWl an10t.inlm on hexadecane a marked drop in pH occurred, The intensities of the ions 258 and 225 relative the lowest values occurring about 48 hr after to those of 257 and 224, respectively, showed that inoculation. While the nature of the change in both the 257 and 224 ions contained 16 ti pH was unknown it seemed logical to assume that carbon atoms. Hence, the most probable empiri- some intermediate product of an acidic nature cal formulae of these ions would be C1HJO62+ was accumulating in the culture fluid. Accord- (257) -nad CuHn32+ (224). These data suggest ingly, 1 L of mineral-hexadecane medium was that the substance in question- wa either inoculated with one isolate (strain F IV) and CQi%HS OCI.H,, cetyl pdlmitat;a *di -of after 48 hr of incubation the cells were harvested C1..0, or possibly C.H1^(DH(OH3)O tie and the culture filtrate was evaporated under hemiacetal of cetyl aldehyde and t l reduced pressure to a volume of approximately Hoeb,the unambiutinra& ee 200 ml. The concentrated filtrate was dissolved for an* hse combined with the.ma-e 64 - in an excess of boiling ethanol, filtered, and con- metri ati cle tt te centrated. White crystals formed upon cooling; is cetyl palmitate. Incidentaly, the these were removed by filtration and recrystal- truinsowed virtually no oin the" w e lized from ethanol to a constant melting point 270 to 470, indicating that both the Alyigoup of 46 to 48 C. Elemental analysis showed that of the eisterae nomal. nitrogen and sulfur were absent. Carbon-hydro- In later identification of oters the.m sale 1959] BACTERIAL HYDROCARBON OXIDATION4443 was calibrated by the addition of an authentic Ester Forriotion Growth aLMoles /IOOML ML/65ML Titrotable sample of n-C36H74 which resulted in the reduction 55C- 0.5 of the uncertainty in the determination of the molecular weight of the intermediate from -14 440 - 04 ( mass units to ±+'y mass units. This alkane, I n-C36H74 gives a set of fragment ions of formula 330 0.3 CnH2,+1+ and CnH2n+ 34 > n > 12, all of about 220 0.2- i equal intensity. An ester, CmnH2m+lCO2CkH2k+1, has its parent peak at 3 mass units greater than 110: 0.1 Cm+k+3H2(m+k+3)+l. It has been established that the characteristic fragment ions in an ester mass spectrum are CmH2m+lCO2H2+ and CmH2m+1- CO2H+, with relative intensity approximately Figure 1. Growth and ester production of the 5/1, and CkH2k+ where this ion is of intensity gram-negative coccus H.O.1 growing on n- those of the acid moiety.
Load more

Recommended publications
  • United States Patent (19) 11) 4,282,163 Suzuki Et Al
    United States Patent (19) 11) 4,282,163 Suzuki et al. 45) Aug. 4, 1981 (54) METHOD OF PRODUCING (56) References Cited HYDROGENATED FATTY ACIDS U.S. PATENT DOCUMENTS 1,247,516 11/1917 Ellis ...................................... 260/409 75 Inventors: Masao Suzuki, Nishinomiya; Takeshi 1927,850 9/1933 Schellmann et al. ................ 260/409 Matsuo; Naomichi Yamada, both of 2,862,943 12/1958 Wheeler ............................... 260/419 Amagasaki, all of Japan 3,197,418 7/1965 Maebashi ... 260/409 3,896,053 7/1975 Broecker et al. 260/409 4,163,750 8/1979 Bird et al. ............................ 260/409 73) Assignee: Nippon Oil and Fats Co., Ltd., Japan 4,179,454 12/1979 Mehta et al. ......................... 260/409 Primary Examiner-John F. Niebling (21) Appl. No.: 102,533 Attorney, Agent, or Firm-Stevens, Davis, Miller & Mosher 22 Filed: Dec. 11, 1979 57 ABSTRACT Hydrogenated fatty acid having excellent color and 30 Foreign Application Priority Data stability can be obtained by hydrogenating fatty acid, oil or fat, and distilling the crude hydrogenated fatty Dec. 19, 1978 JP Japan ................................ 53-157101 acid; or splitting the hydrogenated oil or fat into crude hydrogenated fatty acid and distilling the crude 51) Int. Cl.............................. .................. C11C3/12 hydrogenated fatty acid. 52) U.S. Cl. ..................................... 260/409; 260/419 58 Field of Search ................................ 260/409, 419 10 Claims, No Drawings 4,282,163 2 and acid oils formed as a by-product in the purification
    [Show full text]
  • Summaries of FY 1991 Research in the Chemical Sciences
    )Is - I~ )~i~TiI ~i*ii i~T -~~~~~~~~~~~~~~~~~~-l 9~~~~~~~~~~rsrr A S.~~~~~~~:Ir I... - - 0~Iii Available to DOE and DOE contractors from the Office of Scientific and Technical Information, P.O. Box 62, Oak Ridge, TN 37831; prices available from (615) 576-8401, FTS 626-8401. Available to the public from the National Technical Information Service, U.S. Department of Commerce, 5285 Port Royal Rd., Springfield, VA 22161. DOE/ER-01 44/9 (DE91011221) August 1991 Distribution Categories UC-400 and UC-401 Summaries of FY 1991 Research in the Chemical Sciences U.S. Department of Energy Office of Energy Research b^~~~~~~~~~~~~ ~~~~~Division of Chemical Sciences I This report was compiled for the Office of Energy Research from project summaries contained in the Research-In-Progress (RIP)database of the Office of Scientific and Technical Information, Oak Ridge, ; ^<-<~~~~~~~~~~~~~~ ~~Tennessee. The RIP database describes new and jr';(;-i~~~~~~~~ l ~~~~~~ongoingenergy and energy-related research projects carried out or sponsored by the Department of Energy. s .» \ Contents PREFACE vii University of Arizona 34 CHEMICAL SCIENCES DIVISION viii Boston University 34 PROGRAM SUMMARIES ix Brandeis University 34 LABORATORY ADMINISTRATION xi California Institute of Technology 35 University of California, Berkeley 35 NATIONAL LABORATORIES University of California, Irvine 35 Photochemical and Radiation Sciences University of California, Los Angeles 36 Ames Laboratory 1 University of California, Santa Barbara 36 Argonne National Laboratory 2 Clemson University
    [Show full text]
  • ACTIVATION of N-HEXANE USING VANADIUM-EXCHANGED ZEOLITES by THIRUSHA NAICKER
    ACTIVATION OF n-HEXANE USING VANADIUM-EXCHANGED ZEOLITES BY THIRUSHA NAICKER Submitted in fulfilment of the academic requirements for the degree of Doctor of Philosophy in the School of Chemistry, University of KwaZulu-Natal, Durban July 2010 As the candidate’s supervisor I have/have not approved this thesis/dissertation for submission Signed: _______________ Name: _______________ Date: __________ DEDICATION To my dad and mum, I love you lots. ii ABSTRACT The influence of the form of the ZSM-5 zeolite, vanadium content and the elimination of the exterior surface acidity on the activity and selectivity of n-hexane oxidation was studied using a fixed bed reactor. Blank reactor studies (carborundum packed reactor) showed no conversion below 450°C with the highest conversion (8%) at 500°C. The dominant products were found to be carbon oxides (Sel./% = 90) with minor selectivities to the hexene isomers (7%) and the remainder being cracked products, THF and benzene. H-ZSM-5 with different SiO2/Al2O3 ratios (100 and 320) and Na-ZSM-5 (SiO2/Al2O3 ratio of 100) were tested under non-oxidative and oxidative conditions. Under oxidative conditions as the ratio of the SiO2/Al2O3 increased, the aluminium content decreased and so too did the cracking ability of the zeolite (i.e. yield of cracked products dropped from 36% to 8%). However, the use of the Na- form of ZSM-5 completely eliminated acid cracking. Under oxidative conditions H-ZSM-5 (100) was found to be more active and resulted in higher formation of cyclic and aromatic compounds. With increasing time on-stream and higher temperatures the catalyst was found to deactivate.
    [Show full text]
  • Paraffin Oxidation Studies
    International Journal of Engineering Innovation & Research Volume 2, Issue 1, ISSN: 2277 – 5668 Paraffin Oxidation Studies Mrs. S. J. Purohit, Dr. Milind Pradhan Prof. Purohit S. J. is a Research Scholar at Bhagwant University & Working at Thadomal Shahani Engg. College, Bandra Mumbai-50. Email:[email protected] Abstract – The oxidation of paraffin has been studied with Many processes were developed to manufacture fatty keen interest by several workers from all over the world; as acids of various molecular weights. The manufacture of oxidation leads to the introduction of various functional higher fatty alcohols; which have potential uses as starting groups in hydrocarbon chains. Processes involving the material for the manufacturing of lubricating oil, additives, Oxidation of Paraffin’s in the liquid phase, using air or synthetic lubricating oil, plasticizers and others. A more oxygen are of great importance to industrialized economies because of their role in converting petroleum hydrocarbon selective process for the oxidation of paraffin to alcohols feed stocks such as alkanes, olefins and aromatics into has been conducted by Bashkirov , khim and co workers; industrial organic chemicals important in the polymer, who conducted the reaction in the presence of Boric acid. petrochemicals ,cosmetics and detergent industries. The alcohols are stabilized in the form of their esters; The oxidation leads predominantly to the formation of which are resistant to further oxidation and hence very secondary alcohols consisting of a mixture of all possible high selectivity is achieved.[2,3] isomers with the same number of carbon atoms in the Paraffin oxidation mechanism molecules as the initial hydrocarbons. The secondary 1st stage alcohols which are oxidation products of paraffin exhibit excellent hydrolytic, oxidative and color stability, because of Hydrocarbon → Hydro peroxide the nature of their branching.
    [Show full text]
  • Oxidation Stability of Fuels in Liquid Phase Karl Chatelain
    Oxidation stability of fuels in liquid phase Karl Chatelain To cite this version: Karl Chatelain. Oxidation stability of fuels in liquid phase. Chemical engineering. Université Paris- Saclay, 2016. English. NNT : 2016SACLY020. tel-01958391 HAL Id: tel-01958391 https://pastel.archives-ouvertes.fr/tel-01958391 Submitted on 18 Dec 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. NNT : 2016SACLY020 THÈSE DE DOCTORAT DE L’UNIVERSITE PARIS-SACLAY préparée à L’ENSTA ParisTech ÉCOLE DOCTORALE N±579 Sciences Mécaniques et Énergétiques, Matériaux et Géosciences (SMEMAG) Spécialité de doctorat : Génie des procédés par Karl CHATELAIN Etude de la stabilité à l’oxydation des carburants en phase liquide Thèse présentée et soutenue à Rueil-Malmaison, le 15 décembre 2016 Composition du jury : Dr. André NICOLLE Président IFP Energies nouvelles, R102 Pr. Richard WEST Rapporteur Northeastern University, Boston, CoMoChEng Pr. Pierre-Alexandre GLAUDE Rapporteur CNRS Nancy, LRGP Dr. Mickael SICARD Examinateur ONERA, DEFA Dr. Thomas DUBOIS Examinateur TOTAL ACS Dr. Laurie STARCK Examinateur IFP Energies nouvelles, R104 Mme. Arij BEN AMARA Examinateur IFP Energies nouvelles, R104 Pr. Laurent CATOIRE Directeur de Thèse ENSTA ParisTech, Université Paris-Saclay, UCP ii Acknowledgements This work was made possible thanks to the support of the IFP Energies nouvelles (IFPEN) and the chemical engineering laboratory (UCP) of the ENSTA ParisTech, Université Paris-Saclay.
    [Show full text]
  • I Finai Summary
    NASA CONTRACTOR NASA CR-1104 REPORT I Finai Summary , NATIONAL AERONAUTICS ,4ND SPACE ADMINISTRATION WASHINGTON, D. C. JULY 1968 NASA CR-1104 STUDY OF METHODS FOR CHEMICAL SYNTHESIS OF EDIBLE FATTY ACIDS AND LIPIDS Final Summary Edited by John W. Frankenfeld Distribution of this report is provided in the interest of information exchange. Responsibility for the contents resides in the author or organization that prepared it. Prepared under Contract No. NAS 2-3708 by ESSO RESEARCH AND ENGINEERING COMPANY Linden, N.J. for Ames Research Center NATIONAL AERONAUTICS AND SPACE ADMINISTRATION For sale by the Clearinghouse for Federal Scientific and Technical Information Springfield, Virginia 22151 - CFSTI price $3.00 PRECEDING PAGE BLANK NOT FILMED. I* The authors wish to express their appreciation for the assistance V PRECEDING PAGE BLANK NOT FILMED. CONTENTS Page LIST OF FIGURES ix LIST OF TABLES X SUMMARY 1 INTRODUCTION 2 Human Energy Requirements - Advantages of Fats 2 Statement of the Problem 3 Approach - Assumptions 4 TECHNICAL Di SCiiSSION 6 Historical - The German Process 6 REDUCTIVE POLYMERIZATION OF CARBON MONOXIDE 10 The Fischer-Tropsch Synthesis 10 Wax Cracking and Oxidative Dehydrogenation 19 The Ziegler Reaction 20 Telomerization of Ethylene and Acetylene 25 SYNTHESIS OF ETHnENE AND CONVERSION OF Cog TO CO 26 Ethylene y& Methane and Acetylene 26 Reduction of Carbon Dioxide to Carbon Monoxide 29 Conversion of Carbon Monoxide to Ethylene 31 CONVERSION OF HYDROCARBONS TO ACIDS 34 Oxidation of Paraffins 34 Oxidation of Olefins 34 Ozonolysis
    [Show full text]
  • United States Patent Office Patented Aug
    ..., 2,846,330 United States Patent Office Patented Aug. 5, 1958 1. 2 2,846,330 mixing may be carried out in the presence of Solvents, for example benzine or turpentine oil, and it is not neces WAX CoMPOSITIONS sary to separate the wax components before they are Erich Berthold, Hans Hoyer, and Guido von Rosenberg, finally worked up to yield, for example shoe creams or Gersthofen, Germany, assignors to Farbwerke Hoechst floor waxes. - . Aktiengesellschaft vormals Meister Lucius & Bruning, The preferred ratio of wax acids to fatty acids is be Frankfurt am Main, Germany, a corporation of Ger tween 75 and 97 parts of wax acids and 25 and 3 parts many of fatty acids, a ratio between 85 and 96 parts of wax No Drawing. Application December 31, 195 acids and 15 and 4 parts of, fatty acids being especially Serial No. 479,213 10 advantageous. The metal content generally ranges from 0.5 percent to 10 percent, preferably from 1 percent to Claims priority, application Germany December 31, 1953 5 percent, calculated upon the total amount of the par 8 Claims. (Cl. 106-268) tially saponified mixture of esters. The ratio of calcium and the second metal may be chosen at will, the preferred The present invention relates to compositions of wax, ratio lying within the range from 1:5 to 5:1. w fatty acid esters and fatty acid salts. Among the salts mentioned above zinc salts are of It is known to prepare and use waxes containing, in special advantage. - addition to the esters of the acids obtained by chromic Particularly suitable acid components are, beside the acid oxidation of montana wax, calcium salts of the said oxidation products of montana wax having an acid num acids.
    [Show full text]
  • Fischer-Tropsch Refining
    Fischer-Tropsch Refining by Arno de Klerk A thesis submitted in partial fulfillment of the requirements for the degree Philosophiae Doctor (Chemical Engineering) in the Department of Chemical Engineering Faculty of Engineering, the Built Environment and Information Technology University of Pretoria Pretoria South Africa February 2008 Fischer-Tropsch Refining Author: Arno de Klerk Promoter: Prof. Philip L. de Vaal Department: Department of Chemical Engineering, University of Pretoria Degree: Philosophiae Doctor (Chemical Engineering) Synopsis Energy carriers, such as coal, natural gas and biomass, can be converted by Fischer-Tropsch technology into synthetic crude (syncrude). Fischer-Tropsch derived syncrude can then be refined to transportation fuels, such as motor-gasoline, jet fuel and diesel fuel. These fuels meet the same specifications as crude oil derived transportation fuels. Conventional refining technologies have to be adapted to deal with Fischer-Tropsch syncrudes, because they differ significantly from crude oil with respect to composition. Some of the key differences are the high concentration of oxygenates and olefins and absence of sulphur in Fischer-Tropsch syncrude. Imposing a crude oil refining methodology on syncrude can lead to unwieldy and expensive refineries. Yet, despite an abundance of literature of Fischer-Tropsch synthesis, there is little literature that deals with the refining of Fischer-Tropsch syncrude. The present study investigated current refining practice for both crude oil and Fischer- Tropsch syncrude in order to identify fundamental differences in their refining focus and conversion behaviour. This was followed by a critical evaluation of the compatibility of syncrudes from high temperature Fischer-Tropsch (HTFT) and low temperature Fischer- Tropsch (LTFT) synthesis with the chemistry and catalysis of various conversion processes.
    [Show full text]
  • LD5655.V856 1987.C666.Pdf
    DESIGN AND C.HARACTERrZA'.rION OF ZEOLITE SUPPORTED COBALT CARBONYL CATALYSTS by Melissa Clare Connaway Dissertation sul::xnitted to the Faculty of the Virginia Polytechnic Institute and State University in partial fulf illroent of the requirements for the degree of OOCTOR OP PHILOSOPKY in Chemistry APPROVED: a. E. Hanson, Chairman J. G. Dillard J. M. Tan'i?o M.. E. Davis July, 1987 Blacksburg, Virginia DES!G~ AND CHARACTERIZATION OF ZEOLITE SUPPORTED COBALT CARBONYL CATALYSTS by Melissa Clare Connaway Comlni ttee Chairman: Brian E. Hanson Chemistry (ABSTRACT) Transition metal compounds such as co2 (C0) 8 have often been used to catalyze variuus organic reactions. Severe difficulties may be ancountered when atte1npts are made to recover and separate the soluble ~atalysts. A heterogeneous system consisting of co2 (C0) 8 impregnated on zeolites with faujasitic structure has been designed and investigated using a variety of techniques. In situ FTIR spectroscopy and carbon monoxide evolution were used to identify the major products generated, namely co4 (C0) 12 and Co(C0) 4 • Disproportionation may be induced thus forming Co(C0) 4 and an associated cation from the supported subcarbonyls by additi.on o.t various ligands such as methanol. The location of the supported cobalt carbonyls is determined by their reactivity toward various pnosphi.1es wi.tn various kineti.c diameters. rhe materials prepared in chis manner were found to be active in cat.ilyzing tae metha11ol carbonylation reaction and following thermolysis w~re also found to be active Fischer-Tropsch catalysts. Major products observed in the carbunylaciJn of methanol were methyl acetate and an acetaldehydd dimetnyl aceta1.
    [Show full text]
  • The Processing of Wax and Wax Additives with Supercritical Fluids
    The processing of wax and wax additives with supercritical fluids By Cara Elsbeth Schwarz Dissertation presented for the Degree of DOCTOR OF PHILISOPHY (Chemical Engineering) In the Department of Process Engineering At the University of Stellenbosch Promoted by Prof. I. Nieuwoudt Prof. J.H. Knoetze Stellenbosch December 2005 Declaration I, the undersigned, hereby declare that the work contained in this thesis is my own original work and that I have not previously in its entirety or in part submitted it at any university for a degree. Cara Elsbeth Schwarz 16 September 2005 i ii Abstract Waxes have many potential uses but large-scale application is hampered by their virtual insolubility. By grafting the wax with a polyethylene glycol segment to form an alcohol ethoxylate, the solubility of the wax in commercial solvents is significantly increased. Alcohol ethoxylates are produced by the polymerisation addition of ethylene oxide onto an oxidised wax. Current methods of alcohol ethoxylate production from alcohols lead to wide ethylene oxide addition distribution and large quantities of residual alcohol. The objective of this study is to provide a method for narrowing the ethylene oxide distribution and to reduce the residual alcohol content. It is proposed to concentrate the alcohol ethoxylate in a post-production separation process using supercritical fluid extraction. The system is modelled to contain three pseudo-components: an alkane, an alcohol and an alcohol ethoxylate. Propane is selected as the supercritical solvent of choice due to the large solubility difference between the alkane and polyethylene glycol. Lower molecular weight alkane phase equilibrium data with propane is abundant but extrapolation to higher molecular weights requires further investigation as it may be complicated by molecular folding.
    [Show full text]
  • METHYL KETONE METABOLISM in HYDROCARBON-UTILIZING MYCOBACTERIA Cane-I-C'4. Aliphatic Alkane-Utilizing Mycobac
    METHYL KETONE METABOLISM IN HYDROCARBON-UTILIZING MYCOBACTERIA H. B. LUKINS' AND J. W. FOSTER Department of Microbiology, The University of Texas, Austin, Texas Received for publication 15 December 1962 ABSTRACT which micro- LUKINS, H. B. (University of Texas, Austin) The most common means by in organisms utilize aliphatic, saturated hydrocar- AND J. W. FOSTER. Methyl ketone metabolism bons is an oxidative attack at a terminal methyl hydrocarbon-utilizing mycobacteria. J. Bacteriol. group (for literature see Fuhs, 1961; Foster, 1962a, 85: 1074-1087. 1963.-Speciesof Mycobacterium especially M. smegmatis 422, produced the homol- b). The usual first, stable product is the homol- ketones the oxidation of ogous primary alcohol which is further converted ogous methyl during to this in turn propane, n-butane, n-pentane, or n-hexane. A the corresponding fatty acid; carrier-trapping experiment demonstrated the undergoes beta-degradation of the carbon chain. formation of 2-undecanone, as well as 1,11-un- As early as 1932, methyl ketones were sus- the oxidation of unde- pected of being involved in paraffin oxidation; decanedioic acid, during Aspergillus versicolor, which grew at the expense cane-i-C'4. Aliphatic alkane-utilizing mycobac- of was teria were able to at the of several long-chain paraffins, also able to grow at grow expense the expense of related methyl ketones (Hopkins aliphatic methyl ketones as sole sources of carbon. and Other ketones which did not support growth Chibnall, 1932). Recently, Pseudomonas were oxidized by resting bacterial suspensions. M. methanica was discovered to produce methyl smegmatis 422 cells grown on propane or acetone ketones, along with alcohols and fatty acids, were simultaneously adapted to oxidize both during the oxidation of gaseous alkanes (Lead- substrates, as well as n-propanol.
    [Show full text]
  • Structural Effects on Arthrobacter ATCC 25581 Methylene Hydroxylase Activity
    AN ABSTRACT OF THE THESIS OF STEVEN SHIN HAYASAKA for theMASTER OF SCIENCE (Name of student) (Degree) 1 ' in MICROBIOLOGY presented on 2k INV (Major) Darce) Title: STRUCTURAL EFFECTS ON ARTHROBACTER ATCC 25581 METHYLEN YDRS MCTIVITY Redacted for Privacy Abstract approved: Dr. D. A. Klein Arthrobacter ATCC 25581, capable of subterminal oxidation of n-hexadecane to 2-, 3-, and 4- alcoholic and ketonic products, was examined for the ability of this methylene hydroxylase capability to be induced and repressed, and for structural relationships influ- encing methylene function oxidation. Induction was best carried out by use of n-alkanes from 10 to 1 6 carbons in length, and was especially strong with methylcyclo- hexane among cyclic compounds tested.Induction was not observed with related alcohols,1 -unsaturate compounds or by methoxy and ethoxy compounds tested.After induction, n-alkanes C14 and C16 carbons in length were transformed to the corresponding internal oxidation products; however, no activity was observed with shorter chain length even-carbon alkanes.Hexadecene-1 and all alcohols tested, including cyclododecanol, were transformed to corresponding ketonic or aldehydic products.Cyclic compounds tested, including cyclododecane, were not oxidized by induced cells, suggesting the role of a methyl group in orientation of the substrate for the methylene hydroxylation, but that the methyl function was not as critical after completion of the hydroxylation step, regardless of structural config- uration.Acetate, a preferred growth substrate for this isolate, was able to repress induction of n-hexadecane methylene hydroxylase activity. Inducibility of methylene hydroxylase activity was confirmed by use of cell-free systems, using methylcyclohexane as an inducer.
    [Show full text]