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Pyrolytic

An interesting question that arises is what happens when a thick adsorbed film (such as reported at for various liquids on glass [144] and for water on pyrolytic carbon [135]) is layered over with bulk liquid. That is, if the solid is immersed in the liquid adsorbate, is the same distinct and relatively thick interfacial film still present, forming some kind of discontinuity or interface with bulk liquid, or is there now a smooth gradation in properties from the surface to the bulk region This type of question seems not to have been studied, although the answer should be of importance in fluid flow problems and in formulating better models for adsorption phenomena from solution (see Section XI-1). [Pg.378]

VDP processes using means other than the pyrolytic cleavage of DPX (Gorham process) to generate the reactive monomer are also known, although none are practiced commercially at the time of this writing (ca 1997). [Pg.430]

Although DPXC and DPXD prepared by the chlorination of DPXN are relatively complex mixtures, after pyrolytic cleavage the resulting mixture... [Pg.430]

Solution Polymers. Acryflc solution polymers are usually characterized by their composition, solids content, viscosity, molecular weight, glass-transition temperature, and solvent. The compositions of acryflc polymers are most readily determined by physicochemical methods such as spectroscopy, pyrolytic gas—liquid chromatography, and refractive index measurements (97,158). The solids content of acryflc polymers is determined by dilution followed by solvent evaporation to constant weight. Viscosities are most conveniently determined with a Brookfield viscometer, molecular weight by intrinsic viscosity (158), and glass-transition temperature by calorimetry. [Pg.171]

M. J. Drews, C. W. Jarvis, and G. C. Lickfield, Temay Reactions AmongPolymer Substrate—Organohalogen—Antimony Oxides Under Pyrolytic, Oxidative and Flaming Conditions, NIST-GCR-89-558, U.S. Department of Commerce, Gaithersburg, Md., 1989. [Pg.473]

Pyrolytic routes to hexafluorobenzene have also attracted attention but have not been commercialized. Pyrolysis of tribromofluoromethane [353-54-8] CBr F, at 630—640°C in a platinum tube gives hexafluorobenzene in 55% yield (251—253). The principal disadvantage of this process is the low weight yield of product 90% of the costly CBr F that is charged is lost as bromine. Of economic potential is the related copyrolysis of dichlorofluoromethane [754-34-0] and chlorofluoromethane [593-70-4] (254,255). [Pg.328]

Thermochemical Liquefaction. Most of the research done since 1970 on the direct thermochemical Hquefaction of biomass has been concentrated on the use of various pyrolytic techniques for the production of Hquid fuels and fuel components (96,112,125,166,167). Some of the techniques investigated are entrained-flow pyrolysis, vacuum pyrolysis, rapid and flash pyrolysis, ultrafast pyrolysis in vortex reactors, fluid-bed pyrolysis, low temperature pyrolysis at long reaction times, and updraft fixed-bed pyrolysis. Other research has been done to develop low cost, upgrading methods to convert the complex mixtures formed on pyrolysis of biomass to high quaHty transportation fuels, and to study Hquefaction at high pressures via solvolysis, steam—water treatment, catalytic hydrotreatment, and noncatalytic and catalytic treatment in aqueous systems. [Pg.47]

The first is a pyrolytic approach in which the heat dehvered by the laser breaks chemical bonds in vapor-phase reactants above the surface, allowing deposition of the reaction products only in the small heated area. The second is a direct photolytic breakup of a vapor-phase reactant. This approach requires a laser with proper wavelength to initiate the photochemical reaction. Often ultraviolet excimer lasers have been used. One example is the breakup of trimethyl aluminum [75-24-1] gas using an ultraviolet laser to produce free aluminum [7429-90-5], which deposits on the surface. Again, the deposition is only on the localized area which the beam strikes. [Pg.19]

Essential Oils. Essential oils are produced by distillation of flowers, leaves, stems, wood, herbs, roots, etc. Distillations can be done directly or with steam. The technique used depends mosdy on the desired constituents of the starting material. Particular care must be taken in such operations so that undesired odors are not introduced as a result of pyrolytic reactions. This is a unique aspect of distillation processing in the flavor and fragrance industry. In some cases, essential oils are obtained by direct expression of certain fmits, particular of the citms family. These materials maybe used as such or as distillation fractions from them (see Oils, essential). [Pg.76]

Conrad Industries, Inc. (CentraUa, Washington) and Clean Air Products Company (Pordand, Oregon) have jointiy built a tire pyrolysis demonstration machine which allows recovery of combustible gases, oils, and other by-products. The equipment can also handle other carbonaceous material. It is designed to process 0.9 t/h of tires the entire system is estimated to cost about 2.3 x 10 . The feedstock consists of 5-cm tires chips which produce pyrolytic filler, a vapor gas yielding 11.5 kj/m (1000 Btu/ft ), and medium and light oils yielding about 42 MJ/kg (18,000 Btu/lb) (32). [Pg.14]

Enerco, Inc. (Yardley, Pennsylvania) has a 600 tine/d demonstration pyrolysis plant located in Indiana, Pennsylvania. The faciUty operated 8 h/d, 5 d/wk for six months. The process involves pyrolysis in a 5.4 t/d batch-operated retort chamber. The heated tines are broken down to cmde oil, noncondensable gases, pyrolytic filter, steel (qv), and fabric waste. In this process, hot gases are fed direcdy to the mbber rather than using indirect heating as in most other pyrolyses. The pyrolysis plant was not operating as of early 1996. [Pg.15]

Kutrieb Corporation (Chetek, Wisconsin) operates a pyrolator process for converting tires into oil, pyrolytic filler, gas, and steel. Nu-Tech (Bensenvike, Illinois) employs the Pyro-Matic resource recovery system for tire pyrolysis, which consists of a shredding operation, storage hopper, char-coUection chambers, furnace box with a 61-cm reactor chamber, material-feed conveyor, control-feed inlet, and oil collection system. It is rated to produce 272.5 L oil and 363 kg carbon black from 907 kg of shredded tires. TecSon Corporation (Janesville, Wisconsin) has a Pyro-Mass recovery system that pyroly2es chopped tire particles into char, oil, and gas. The system can process up to 1000 kg/h and produce 1.25 MW/h (16). [Pg.15]

Other techniques include oxidative, steam atmosphere (33), and molten salt (34) pyrolyses. In a partial-air atmosphere, mbber pyrolysis is an exothermic reaction. The reaction rate and ratio of pyrolytic filler to ok products are controlled by the oxygen flow rate. Pyrolysis in a steam atmosphere gives a cleaner char with a greater surface area than char pyroly2ed in an inert atmosphere however, the physical properties of the cured compounded mbber are inferior. Because of the greater surface area, this pyrolytic filler could be used as activated carbon, but production costs are prohibitive. Molten salt baths produce pyroly2ed char and ok products from tine chips. The product characteristics and quantities depend on the salt used. Recovery of char from the molten salt is difficult. [Pg.15]

Carbon, Carbides, and Nitrides. Carbon (graphite) is a good thermal and electrical conductor. It is not easily wetted by chemical action, which is an important consideration for corrosion resistance. As an important stmctural material at high temperature, pyrolytic graphite has shown a strength of 280 MPa (40,600 psi). It tends to oxidize at high temperatures, but can be used up to 2760°C for short periods in neutral or reducing conditions. The use of new composite materials made of carbon fibers is expected, especially in the field of aerospace stmcture. When heated under... [Pg.26]

Biomedical. Heart-valve parts are fabricated from pyrolytic carbon, which is compatible with living tissue. Such parts are produced by high temperature pyrolysis of gases such as methane. Other potential biomedical apphcations are dental implants and other prostheses where a seal between the implant and the living biological surface is essential. Plasma and arc-wire sprayed coatings are used on prosthetic devices, eg, hip implants, to achieve better bone/tissue attachments (see Prosthetic and BiOLffiDiCALdevices). [Pg.51]

Thin vitreous sHica films are usually formed by vapor depositioa or r-f sputteriag (see Thin films, film-DEPOSITION techniques). Vapor depositioa is geaerally effected by the pyrolytic decompositioa of tetraethoxysHane or another alkoxysHane. SHica has been most extensively used ia r-f sputteriag of... [Pg.512]

Chemical Analysis. The presence of siUcones in a sample can be ascertained quaUtatively by burning a small amount of the sample on the tip of a spatula. SiUcones bum with a characteristic sparkly flame and emit a white sooty smoke on combustion. A white ashen residue is often deposited as well. If this residue dissolves and becomes volatile when heated with hydrofluoric acid, it is most likely a siUceous residue (437). Quantitative measurement of total sihcon in a sample is often accompHshed indirectly, by converting the species to siUca or siUcate, followed by deterrnination of the heteropoly blue sihcomolybdate, which absorbs at 800 nm, using atomic spectroscopy or uv spectroscopy (438—443). Pyrolysis gc followed by mass spectroscopic detection of the pyrolysate is a particularly sensitive tool for identifying siUcones (442,443). This technique rehes on the pyrolytic conversion of siUcones to cycHcs, predominantly to [541-05-9] which is readily detected and quantified (eq. 37). [Pg.59]

Temperature. The temperature for combustion processes must be balanced between the minimum temperature required to combust the original contaminants and any intermediate by-products completely and the maximum temperature at which the ash becomes molten. Typical operating temperatures for thermal processes are incineration (750—1650°C), catalytic incineration (315—550°C), pyrolysis (475—815°C), and wet air oxidation (150—260°C at 10,350 kPa) (15). Pyrolysis is thermal decomposition in the absence of oxygen or with less than the stoichiometric amount of oxygen required. Because exhaust gases from pyrolytic operations are somewhat "dirty" with particulate matter and organics, pyrolysis is not often used for hazardous wastes. [Pg.168]

Polyhedral Expansion. The term polyhedral expansion is used to describe a host of reactions in which the size of the polyhedron is increased by the addition of new vertex atoms whether boron, heteroelements, or metals. In the case of the boranes, the pyrolysis of B2H has been used to obtain B H and industrially. Although a subject of much study, the mechanism of such pyrolytic expansions is not well understood. [Pg.236]


See other pages where Pyrolytic is mentioned: [Pg.365]    [Pg.15]    [Pg.207]    [Pg.4]    [Pg.68]    [Pg.7]    [Pg.276]    [Pg.88]    [Pg.33]    [Pg.270]    [Pg.55]    [Pg.213]    [Pg.391]    [Pg.391]    [Pg.392]    [Pg.392]    [Pg.14]    [Pg.14]    [Pg.14]    [Pg.50]    [Pg.279]    [Pg.366]    [Pg.422]    [Pg.451]    [Pg.583]    [Pg.116]    [Pg.495]    [Pg.508]   
See also in sourсe #XX -- [ Pg.250 ]

See also in sourсe #XX -- [ Pg.88 , Pg.108 , Pg.109 , Pg.110 , Pg.112 , Pg.113 ]

See also in sourсe #XX -- [ Pg.1349 ]




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Acid derivatives, pyrolytic reactions

Acids pyrolytic reactions

Amorphous carbon materials pyrolytic carbons

And pyrolytic eliminations

Basal plane pyrolytic graphite

Basal plane pyrolytic graphite electrode

Boron nitride pyrolytic

Carbidization pyrolytic coatings

Carbon highly ordered pyrolytic

Carbon pyrolytic graphite

Carbon pyrolytic production

Carbon pyrolytic, coupled

Ceramic materials pyrolytic ceramization

Decomposition of Hydrocarbons-Pyrolytic Methods

Derivative Approach - Pyrolytic Dehydrogenation of Benzene

Edge plane pyrolytic graphite

Edge plane pyrolytic graphite electrode

Ei elimination, pyrolytic Cope reaction

Ei elimination, pyrolytic stereoselectivity

Elaeokanines via pyrolytic dehydrosulfinylation

Electrochemistry at Highly Oriented Pyrolytic Graphite (HOPG) Toward a New Perspective

Electrode highly oriented pyrolytic graphite

Electrodes pyrolytic

Electrothermal atomizers pyrolytic graphite

Elimination pyrolytic, coupled

Elimination reactions pyrolytic

Eliminations pyrolytic

Elimination—addition pyrolytic

Fast pyrolytic processes

Free enthalpy for pyrolytic reactions

Further pyrolytic reactions during cellulose pyrolysis

Glassy carbon and pyrolytic graphite

Graphite edge pyrolytic

Graphite oriented pyrolytic

Graphite, pyrolytic, oxidation rates

HOPG (highly ordered pyrolytic

Halogens pyrolytic elimination reactions

Halogens pyrolytic reactions

High-density outer pyrolytic carbon

High-oriented pyrolytic graphite

High-oriented pyrolytic graphite HOPG)

Highly Ordered Pyrolytic Graphite and the Influence of Defects

Highly Oriented Pyrolytic

Highly ordered pyrolytic graphite

Highly ordered pyrolytic graphite (HOPG

Highly ordered pyrolytic graphite production

Highly orientated pyrolytic graphite

Highly orientated pyrolytic graphite HOPG)

Highly orientated pyrolytic graphite surface

Highly oriented pyrolytic graphene

Highly oriented pyrolytic graphite

Highly oriented pyrolytic graphite (HOPG growth

Highly oriented pyrolytic graphite (HOPG metals

Highly oriented pyrolytic graphite HOPG)

Highly oriented pyrolytic graphite defects

Highly oriented pyrolytic graphite oxidation

Highly oriented pyrolytic graphite scanning electrochemical

Highly oriented pyrolytic graphite stability

Highly oriented pyrolytic graphite step edges

Highly oriented pyrolytic graphite steps

Highly oriented pyrolytic self-assembly

Highly-ordered pyrolytic graphite electrode

Kinetic Factors in Pyrolytic Chemical Reactions

Kinetic factors in pyrolytic reactions

LTI pyrolytic carbon

Liquids, pyrolytic

Liquids, pyrolytic upgrading

Maturity pyrolytic

Methane, pyrolytic

Microorganisms by Pyrolytic Techniques

Of pyrolytic eliminations

Oils/waxes pyrolytic

Ordinary Pyrolytic Graphite

Orientation in Pyrolytic Eliminations

Oxygen pyrolytic reactions

PAHs pyrolytic

PYROLYTIC GASIFICATION

PYROLYTIC LIQUEFACTION

Pressurized, pyrolytic steam process

Properties of Columnar and Laminar Pyrolytic Graphites

Properties of Isotropic Pyrolytic Carbon

Properties of pyrolytic graphite

Pyrolysis/pyrolytic degradation

Pyrolytic BN

Pyrolytic Carbon Heart Valves

Pyrolytic Dehydrogenation of Benzene to Diphenyl and Triphenyl

Pyrolytic Methods

Pyrolytic Processes Compared with Combustion

Pyrolytic Severity Test

Pyrolytic Source

Pyrolytic Techniques Used in Pathology

Pyrolytic alkylation

Pyrolytic analyses

Pyrolytic carbon

Pyrolytic carbon applications

Pyrolytic carbon black

Pyrolytic carbon coating

Pyrolytic carbon deposition

Pyrolytic carbon microelectrodes

Pyrolytic carbon nanotube

Pyrolytic carbon structure

Pyrolytic carbon-coated nuclear

Pyrolytic ceramization

Pyrolytic char

Pyrolytic chromatography

Pyrolytic cleavage

Pyrolytic coke

Pyrolytic conversion

Pyrolytic cracking

Pyrolytic cyclization

Pyrolytic decomposition

Pyrolytic degradation

Pyrolytic deposition rate

Pyrolytic dimerization

Pyrolytic elimination Chugaev

Pyrolytic elimination from esters

Pyrolytic eliminations in the gas phase

Pyrolytic gas chromatography

Pyrolytic gases

Pyrolytic graphite

Pyrolytic graphite as a coating

Pyrolytic graphite disk electrode

Pyrolytic graphite edge electrode

Pyrolytic graphite electrode surfaces

Pyrolytic graphite electrode, cyclic

Pyrolytic graphite electrode, cyclic voltammogram

Pyrolytic graphite electrode, voltammogram

Pyrolytic graphite electrode, working

Pyrolytic graphite electrodes

Pyrolytic graphite high-pressure-annealed

Pyrolytic graphite particles

Pyrolytic graphite ring electrode

Pyrolytic graphite structure

Pyrolytic hydrocarbon

Pyrolytic lignin

Pyrolytic oil

Pyrolytic process

Pyrolytic processing

Pyrolytic production of elemental

Pyrolytic properties

Pyrolytic reaction pathway

Pyrolytic reactions

Pyrolytic reactions oxygen derivatives

Pyrolytic reactors, control

Pyrolytic reformer

Pyrolytic regime

Pyrolytic sublimation

Pyrolytic syn elimination

Pyrolytic synthesis

Pyrolytic systems, modeling

Pyrolytic water

Pyrolytically coated

Pyrolytically coated graphite

Pyrolytically coated graphite cuvettes

Ring opening pyrolytic

STRUCTURE OF PYROLYTIC GRAPHITE

Shock-Induced Phase Transitions in Oriented Pyrolytic Graphite

Stress-annealed pyrolytic graphite

Sulphoxides, pyrolytic elimination

Synthetic methods by pyrolytic extrusions

THE CVD OF PYROLYTIC GRAPHITE

Temperature pyrolytic water evolution

The Pyrolytic Regime

The Various Structures of Pyrolytic Graphite

Theoretical Approaches for Chemical Pyrolytic Reactions

Thermodynamic Factors in Pyrolytic Chemical Reactions

Thiocarbonate pyrolytic elimination

Transition state pyrolytic

Transition states pyrolytic elimination

Working electrode highly ordered pyrolytic

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