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Ammonia modes

MS analysis was conducted on the deactivated catalysts from the MAT reactors using a VG instrument in which the probe was heated from ambient to 500 C at a rate of 20 C min1 and spectra over the mass range 50-600 were recorded every 5s. Spectra were recorded in both electron impact (El) and chemical ionisation (Cl, with ammonia) modes. A number of deactivated samples have also been analysed after extraction in chloroform to remove physically-trapped molecular species. [Pg.378]

Spectra were recorded in both electron impact (El) and chemical ionisation (Cl, with ammonia) modes. A number of deactivated samples have also been analysed after extraction in chloroform to remove physically-trapped molecular species. [Pg.314]

Anhydrous ammonia is moved worldwide ia specially designed vessels, barges, rail cars, and tmcks. AH modes are covered by rigid safety restrictions (8). Ships and barges usuaHy employ refrigeration or semirefrigeration to maintain the Hquid, while rail cars and tmcks normally depend only on pressure... [Pg.218]

Ammonia is usually transported for long distances by barge, pipeline, and rail, and for short distances by tmck Eactors that govern the type of carrier used in anhydrous ammonia transportation systems are distance, location of plant site in relation to consuming area, availabihty of transportation equipment, and relative cost of available carriers. Typical costs (83) of pipeline, barge, and rail modes for long distance transport are 0.0153, 0.0161, and 0.0215 per ton per kilometer, respectively, for distances of about 1600 km. Short distance tmck transportation costs (83) are much higher. Costs are typically 0.0365/(t km) for distances on the order of 160 km. [Pg.356]

In the present work low temperature adsoi ption of fluoroform and CO, were used to characterize surface basicity of silica, both pure and exposed to bases. It was found that adsorption of deuterated ammonia results in appearance of a new CH stretching vibration band of adsorbed CHF, with the position typical of strong basic sites, absent on the surface of pure silica. Low-frequency shift of mode of adsorbed CO, supports the conclusion about such basicity induced by the presence of H-bonded bases. [Pg.56]

These faetors are attributed to bateh and semi-bateh proeesses rather than eontinuous proeesses. However, the use of eontinuous proeesses on fine ehemieal manufaeturing sites is limited. It is often preferable to use the semi-bateh mode as opposed to bateh proeesses. The Appendix lists hazards of pertinent ehemieal reaetions for toxie and reaetive hazards ehemieals. Information eoneerning the safety of various ehemieals (e.g., ammonia and others) ean be readily obtained from the World Wide Web. Table 12-1 shows how to aeeess a material safety data sheet at the Vermont Safety Information (VIRI) site on the Internet. [Pg.917]

The Raman spectroscopic work of Ja-covitz [31], Cornilsen et al. [32, 33], and Audemer et al. [34] is the most direct spectroscopic evidence that the discharge product in battery electrodes, operating of the pi ji cycle, is different from well-crystallized / -Ni(OH)2. The O-H stretching modes and the lattice modes in the Raman spectra are different from those found for well-crystallized Ni(OH)2, prepared by recrystallization from the ammonia complex, and are more similar to those... [Pg.139]

Exchange of ionizable materials, primarily dissolved iron. Here the preferred media/process is resin bead deep-bed polishers. Resins may be operated in different cycle modes and where, for example ammonia, morpholine, or AVT programs are employed, specific operating conditions are necessary to avoid adverse effects of the ammonia anion cycle. [Pg.378]

When urea is heated alone or in aqueous solution it dearranges into ammonia and cyanic acid. The ammonia escapes, and if aniline is present the cyanic acid combines with it to form phenylmea. Phenyliurea dearranges in two modes which correspond to two methods for its formation. [Pg.2]

Acetate kinase is phosphorylated by acetyl phosphate and it has been shown that the phosphoenzyme can synthesise ATP from ADP, and acetyl phosphate from acetate. The mode of decomposition of carbamyl phosphate in aqueous solution is pH dependent and can proceed with either the production of ammonia and carbon dioxide (equation 1), or cyanate (equation 2). No cyanate could be detected during the hydrolysis... [Pg.147]

Oxidations of ammonia display ignition/extinction characteristics and auto-thermal reaction behavior. At low heat supply, only low conversion is observed and temperature remains nearly constant. With increasing heat supply and approaching a certain temperature, the reaction heat generated can no longer be transferred completely totally to the reactor construction material. At this stage, the reaction starts up . Suddenly, the temperature is raised by increased heat production until heat generation and removal are in balance. The reaction can now be carried out without a need for external heat supply, namely in autothermal mode. [Pg.293]

A chemical reactor is an apparatus of any geometric configuration in which a chemical reaction takes place. Depending on the mode of operation, process conditions, and properties of the reaction mixture, reactors can differ from each other significantly. An apparatus for the continuous catalytic synthesis of ammonia from hydrogen and nitrogen, operated at 720 K and 300 bar is completely different from a batch fermenter for the manufacture of ethanol from starch operated at 300 K and 1 bar. The mode of operation, process conditions, and physicochemical properties of the reaction mixture will be decisive in the selection of the shape and size of the reactor. [Pg.257]

Sugihara et al. in 1997.106 They utilized aqueous ammonium hydroxide as a reaction medium, which provided ammonia as a hard ligand to labilize the CO ligands and therefore enhance the rate of the PKR. The reaction of dicobalthexacarbonyl complexes of enynes and alkynes provided expected cyclopentenones via intramolecular and intermolecular modes respectively (Scheme 4.10). [Pg.129]


See other pages where Ammonia modes is mentioned: [Pg.167]    [Pg.452]    [Pg.111]    [Pg.2075]    [Pg.447]    [Pg.186]    [Pg.130]    [Pg.706]    [Pg.1155]    [Pg.175]    [Pg.156]    [Pg.26]    [Pg.15]    [Pg.202]    [Pg.91]    [Pg.309]    [Pg.310]    [Pg.2]    [Pg.395]    [Pg.52]    [Pg.53]    [Pg.292]    [Pg.115]    [Pg.222]    [Pg.293]    [Pg.32]    [Pg.19]    [Pg.125]    [Pg.362]    [Pg.467]    [Pg.114]    [Pg.384]    [Pg.124]    [Pg.88]    [Pg.455]   
See also in sourсe #XX -- [ Pg.396 ]




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