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Methanal oxidation

The process can be operated in two modes co-fed and redox. The co-fed mode employs addition of O2 to the methane/natural gas feed and subsequent conversion over a metal oxide catalyst. The redox mode requires the oxidant to be from the lattice oxygen of a reducible metal oxide in the reactor bed. After methane oxidation has consumed nearly all the lattice oxygen, the reduced metal oxide is reoxidized using an air stream. Both methods have processing advantages and disadvantages. In all cases, however, the process is mn to maximize production of the more desired ethylene product. [Pg.86]

Methane oxidations occur only by intermediate and high temperature mechanisms and have been reported not to support cool flames (104,105). However, others have reported that cool flames do occur in methane oxidation, even at temperatures >400 ° C (93,94,106,107). Since methyl radicals caimot participate in reactions 23 or 24, some other mechanism must be operative to achieve the quenching observed in methane cool flames. It has been proposed that the interaction of formaldehyde and its products with radicals decreases their concentrations and inhibits the whole oxidation process (93). [Pg.340]

The reported characteristics of methane oxidation at high pressures are interesting. As expected,the reaction can be conducted at lower temperatures eg, 262°C at 334 MPa (3300 atm) (100). However, the cool flame phenomenon is observed even under these conditions. At high pressures. [Pg.340]

Ethane. Ethane VPO occurs at lower temperatures than methane oxidation but requires higher temperatures than the higher hydrocarbons (121). This is a transition case with mixed characteristics. Low temperature VPO, cool flames, oscillations, and a NTC region do occur. At low temperatures and pressures, the main products are formaldehyde, acetaldehyde (HCHOiCH CHO ca 5) (121—123), and carbon monoxide. These products arise mainly through ethylperoxy and ethoxy radicals (see eqs. 2 and 12—16 and Fig. 1). [Pg.341]

Aldehydes are important products at all pressures, but at low pressures, acids are not. Carbon monoxide is an important low pressure product and declines with increasing pressure as acids increase. This is evidence for competition between reaction sequence 18—20 and reaction 21. Increasing pressure favors retention of the parent carbon skeleton, in concordance with the reversibiUty of reaction 2. Propylene becomes an insignificant product as the pressure is increased and the temperature is lowered. Both acetone and isopropyl alcohol initially increase as pressure is raised, but acetone passes through a maximum. This increase in the alcohoLcarbonyl ratio is similar to the response of the methanoLformaldehyde ratio when pressure is increased in methane oxidation. [Pg.341]

The overall process for producing a 1 1 CO to ratio by partial methane oxidation and the water gas shift reaction is represented by equation 5. [Pg.465]

R. Hicks and co-workers, Structure Sensitivity of Methane Oxidation overl latinum and Palladium J. Catal, 280—306 (1990). [Pg.498]

The influence of Zn-deposition on Cu(lll) surfaces on methanol synthesis by hydrogenation of CO2 shows that Zn creates sites stabilizing the formate intermediate and thus promotes the hydrogenation process [2.44]. Further publications deal with methane oxidation by various layered rock-salt-type oxides [2.45], poisoning of vana-dia in VOx/Ti02 by K2O, leading to lower reduction capability of the vanadia, because of the formation of [2.46], and interaction of SO2 with Cu, CU2O, and CuO to show the temperature-dependence of SO2 absorption or sulfide formation [2.47]. [Pg.24]

The lower than expected yields can be explained by the nature of methane oxidation to methanol in these bacteria. This reaction, catalysed by methane mono-oxygenase, is a net consumer of reducing equivalents (NADH), which would otherwise be directed to ATP generation and biosynthesis. In simple terms the oxidation of methane to methanol consumes energy, lowering the yield. [Pg.89]

D. Eng, and M. Stoukides, Catalytic and Electrocatalytic Methane Oxidation with Solid Oxide Membranes, Catalysis Reviews - Science and Engineering 33, 375-412 (1991). [Pg.108]

This linear variation in catalytic activation energy with potential and work function is quite noteworthy and, as we will see in the next sections and in Chapters 5 and 6, is intimately linked to the corresponding linear variation of heats of chemisorption with potential and work function. More specifically we will see that the linear decrease in the activation energies of ethylene and methane oxidation is due to the concomitant linear decrease in the heat of chemisorption of oxygen with increasing catalyst potential and work function. [Pg.164]

O.A. Mar ina, V.A. Sobyanin, V.D. Belyaev, and V.N. Parmon, The effect of electrochemical pumping of oxygen on catalytic behaviour of metal electrodes in methane oxidation, in New Aspects of Spillover Effect in Catalysis for Development of Highly Active Catalysts, Stud. Surf. Sci. Catal. 77 (T. Inui, K. Fujimoto, T. Uchijima,... [Pg.186]

Methane oxidation and partial oxidation, electrochemical promotion of, 308 dimerization, 470 reforming, 410 Methanol dehydrogenation electrochemical promotion of, 403 selectivity modification, 404 Methanol oxidation electrochemical promotion of 398 selectivity modification, 400 Microscopy... [Pg.571]

Hydrogen Photosynthetic bacteria, methane oxidation A few years... [Pg.52]

Eng W, Palumbo AV, Sriharan S, et al. 1991. Methanol suppression of trichloroethylene degradation by Methylosinus trichosporium (OB3b) and methane-oxidizing mixed cultures. Appl Biochem Biotechnol 28/29 887-899. [Pg.262]

Jones RD, RY Morita (1983) Methane oxidation by Nitrosococcus oceanus and Nitrosomonas europaea. Appl Environ Microbiol 45 401-410. [Pg.83]

Ward BB (1987) Kinetic studies on ammonia and methane oxidation by Nitrosococcus oceanus. Arch Microbiol 147 126-133. [Pg.90]

Little CD, AV Palumbo, SE Herbes, ME Lidstrom, RL Tyndall, PJ Gilmour (1988) Trichloroethylene biodegradation by a methane-oxidizing bacterium. Appl Environ Microbiol 54 951-956. [Pg.234]

Girguis PR, AE Cozen, EF Delong (2005) Growth and population dynamics of anaerobic methane-oxidizing archaea and sulfate-reducing bacteria in a continuous-flow reactor. Appl Environ Microbiol 71 3725-3733. [Pg.327]

Hallam SJ, PR Girguis, CM Preston, PM Richardson, EF DeLong (2003) Identification of methyl coenzyme M reductase A (merA) genes associated with methane-oxidizing archaea. Appl Environ Microbiol 69 5483-5491. [Pg.634]

Orphan VL, CH Hpuse, K-U Hinrichs, KD McKeegan, EE DeLong (2002) Multiple archaeal groups mediate methane oxidation in anoxic cold seep sediments. Proc Natl Acad USA 99 7663-7668. [Pg.636]

BIOMIMETIC FEATURES OF FeZSM-5 ZEOLITE 3.1. a-Oxygcn methane oxidation... [Pg.497]

In order to identify the product, we used a procedure of its extraction from the surface similar to that used in the case of a-oxygen benzene oxidation [18]. For this purpose, a number of single-tum-over runs in the room temperature methane oxidation were carried out according to the following scheme ... [Pg.498]

NMR analysis of product methanol isotops and KIE values of CH2D2 methane oxidation with... [Pg.499]

From the results discussed above as well as from the literature data [5-10,12-14] it follows that an important role of O2 in the SCR process is to convert NO into NOj. The latter then initiates methane oxidation into CO, and is itself reduced into NO and N2. Both NO, and O2 may participate in CH4 oxidation (Fig. 1B) and the ratio between the rates of these competitive oxidation reactions will be critical for the selectivity of the SCR process. Hence, the absolute rates of CH4 oxidation by Oj were compared with those occurring in the SCR process. The rates of these reactions were determined under different reaction conditions (using the... [Pg.652]

Partial methane oxidation comprises very high rates so that high space-time yields can be achieved (see original citations in [3]). Residence times are in the range of a few milliseconds. Based on this and other information, it is believed that syngas facilities can be far smaller and less costly in investment than reforming plants. Industrial partial oxidation plants are on the market, as e.g. provided by the Syntroleum Corporation (Tulsa, OK, USA). Requirements for such processes are operation at elevated pressure, to meet the downstream process requirements, and autothermal operation. [Pg.322]

Figure 3.43 Conversion rates and product selectivity of partial methane oxidation as a function of the catalyst temperature. Experimental data (points) and calculated thermodynamic values (lines) [112]. Figure 3.43 Conversion rates and product selectivity of partial methane oxidation as a function of the catalyst temperature. Experimental data (points) and calculated thermodynamic values (lines) [112].
Hoffmann, C., Schmidt, H.W. and Schuth, F. (2001) A multipurpose parallelized 49-channel reactor for the screening of catalysts methane oxidation as the example reaction. J. Catal., 198, 348. [Pg.356]


See other pages where Methanal oxidation is mentioned: [Pg.94]    [Pg.369]    [Pg.512]    [Pg.89]    [Pg.330]    [Pg.382]    [Pg.44]    [Pg.151]    [Pg.304]    [Pg.626]    [Pg.628]    [Pg.407]    [Pg.423]    [Pg.493]    [Pg.499]    [Pg.499]    [Pg.35]   
See also in sourсe #XX -- [ Pg.77 ]




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Acetic Acid Production by Ethane and Methane Oxidation

Aerobic microbial oxidation of sulphide and methane

Aerobic oxidation of methane

Aerobic oxidation, methane

Alkali-promoted metal oxide , methane

Alkali-promoted metal oxide , methane activation studies

Anaerobic Oxidation of Methane (AOM)

Anaerobic oxidation of methane

Atmosphere methane oxidation cycle

Bacteria methane oxidation

Biological methane oxidation

Biological oxidation of methane

Carbon dioxide from methane oxidation

Carbon oxides, methanation

Catalysts for partial oxidation of methane

Catalytic methane oxidation

Catalytic oxidative coupling methane

Catalytic partial oxidation of methane

Catalytica methane oxidation

Catalytically active sites oxidative coupling, methane

Ceramic methane, oxidative coupling

Complete Oxidation of Methane

Copper oxide reduction with methane

Coupling methane, oxidative

Direct methane oxidation to methanol under pressure

Direct oxidation of methane-to-methanol

Direct pressurized oxidation of methane to methanol with hydrogen peroxide

Fischer methane oxidation

Fuel methane, direct partial oxidation

Gas Hydrate Carbonate Formation and Anaerobic Oxidation of Methane

Heterogeneous Processes in the Partial Oxidation of Methane to Oxygenates

Heterogeneous catalysis methane oxidative coupling

High-temperature oxidation of natural methane with hydrogen peroxide

Hydrocarbon Reforming 1 Micro Structured Monoliths for Partial Methane Oxidation

Hydrocarbon Reforming 2 Partial Methane Oxidation Heat Exchanger Reactor

Hydrocarbon oxidation methane

Hydrogen methane oxidation

Indirect partial oxidation of methane in a catalytic tubular reactor

Iridium methane oxidative addition

Kinetics of methane oxidation

Membrane reactors, methane partial oxidation

Metal Oxides methane oxidation

Methan oxidation, formation condensation

Methan oxidation, formation condensation products

Methanation of carbon oxides

Methane anaerobic oxidation

Methane and Ammonia Oxidation

Methane and methanol oxidation to formaldehyde

Methane anodic oxidation

Methane combustion with oxides

Methane complete oxidation

Methane continued) oxidation

Methane continued) oxide

Methane controlled oxidation

Methane conversion processes oxidative coupling

Methane conversion processes partial oxidation

Methane electrochemical partial oxidation

Methane fuel oxidation within SOFC

Methane monooxygenase oxidized

Methane nitrogen oxide reduction with

Methane oxidation

Methane oxidation carbonylation

Methane oxidation cycle, troposphere

Methane oxidation high temperature

Methane oxidation methanol

Methane oxidation promotion

Methane oxidation rate constants

Methane oxidation reaction mechanism

Methane oxidation states

Methane oxidation steam reforming

Methane oxidation systems

Methane oxidation, microbial

Methane oxidation, photocatalytic

Methane oxidative addition

Methane oxidative carbonylation

Methane oxidative condensation

Methane oxidative coupling reaction with

Methane oxidative dimerization

Methane oxidative methylation with

Methane oxidative transformations

Methane oxidization

Methane partial oxidation to syngas

Methane partial oxidation to synthesis gas

Methane peroxynitrous acid oxidation

Methane thermal oxidation

Methane thiol, from oxidation

Methane, catalytic partial oxidation

Methane, direct oxidation

Methane, from radiolytic oxidation

Methane, oxidation over perovskites

Methane, oxidative behavior

Methane, partial oxidation

Methane, selective oxidation

Methane, tropospheric oxidation cycle

Methane-oxidizing bacteria

Methanol, production methane oxidation

Methanotrophs (methane-oxidizing

Methyl disulfide, oxidation to methane

Methyl disulfide, oxidation to methane sulfinyl chloride by chlorine

Model methane oxidative coupling

Nickel oxidation of methane

Nickel oxide reduction with methane

Nitrification and Methane Oxidation

Nitrous oxide methane oxidation

Oxidation methane coupling

Oxidation methane exploitation

Oxidation of Methane in the Natural Atmosphere and OH Radical Chain Reaction

Oxidation of Methane on Supported Palladium Under Lean Conditions Kinetics, Structure and Properties

Oxidation of methane

Oxidation of methane over monoliths

Oxidation of methane to methanol

Oxidation products methane conversion

Oxidation products methane—oxygen mixtures

Oxidation-reduction reactions methane fermentations

Oxidative Conversion of Methane to Syngas

Oxidative addition of methane

Oxidative coupling of methan

Oxidative coupling of methane

Oxidative coupling of methane over

Oxidative coupling of methane process

Oxidative coupling of methane to ethane

Oxidative coupling, methane over

Oxidative dimerization of methane

Oxidative methane

Oxidative methane

Oxidative methane activation

Oxygen-permeable membrane methane oxidative coupling

Ozone, atmosphere methane oxidation cycle

Palladium methane oxidation

Partial oxidation and dry reforming of methane

Partial oxidation of methane

Partial oxidation of methane to formaldehyde

Partial oxidation of methane to syngas

Partial oxidation, of methane to synthesis

Photochemical oxidation of methane

Production during methane oxidation

Reaction methane oxidation

Reduction methane oxidation

Rhodium oxidative methane carbonylation

Selective Oxidative Activation of Methane

Selective oxidation of methane

Solid oxide fuel cells methane steam reforming

Sulfate reduction and methane oxidation

Syngas methane partial oxidation reaction

The oxidation of methane

Total Oxidation of Methane

Transition-metal oxides methanation

XPS In Situ Reaction Methane Oxidation

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