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Chemicals ammonium iodide

Economic Aspects and Uses. Ammonium bromide is available as a dry technical grade or as 38 to 45% solutions. It is used to manufacture chemical Hitermediates, and Hi photographic chemicals it also has some flame retardant appHcations. In June 1991, its price was quoted as 2.66/kg. Ammonium iodide has limited use Hi photographic and pharmaceutical preparations. [Pg.364]

At about the same time, BP Chemicals, ivho ivere also licensors of the Monsanto process, developed their oivn process for carbonylation of a mixed MeOH/MeOAc/ H2O feed to AcOH and AC2O using a Rh and Mel catalysed process promoted with a quaternary ammonium iodide salt ([QAS]I), [7]. [Pg.196]

Arsenic triiodide also dissolves, the saturated solution at 15° C. having density 3-661. Other soluble halides are potassium bromide, anhydrous ferric and aluminium chlorides 6 and tetramethyl ammonium iodide but the iodides of rubidium, cadmium, manganese and cobalt, also mercuric and stannic iodides, and cobalt and stannic bromides, are insoluble or only very slightly soluble in arsenic tribromide. The liquid also dissolves phosphoryl bromide and, very slightly, ammonium thiocyanate. In the mixed solutions of halides, the components may react chemically (cf. p. 106), but such is not always the case for example, with antimony tribromide a continuous series of solid solutions is formed.7... [Pg.113]

It is also possible to block GA synthesis chemically using inhibitors such as AMO-l6l8 (68), or the quaternary ammonium iodide compound in Figure 11 X 9,70), which block ent-kaurene formation. [Pg.44]

Chemical Reactions.—Phosphonium iodide is hydrolysed by water, and is still more rapidly decomposed by alkalies, giving phosphine and an iodide. The phosphine is displaced by ammonia giving ammonium iodide,8 and even by ethyl alcohol giving ethyl iodide, with phosphine in both cases.9 It is hardly affected by aqueous acids, except those which are also oxidising agents. [Pg.78]

A process for the coproduction of acetic anhydride and acetic acid, which has been operated by BP Chemicals since 1988, uses a quaternary ammonium iodide salt in a role similar to that of Lil [8]. Beneficial effects on rhodium-complex-catalyzed methanol carbonylation have also been found for other additives. For example, phosphine oxides such as Ph3PO enable high catalyst rates at low water concentrations without compromising catalyst stability [40—42]. Similarly, iodocarbonyl complexes of ruthenium and osmium (as used to promote iridium systems, Section 3) are found to enhance the activity of a rhodium catalyst at low water concentrations [43,44]. Other compounds reported to have beneficial effects include phosphate salts [45], transition metal halide salts [46], and oxoacids and heteropolyacids and their salts [47]. [Pg.10]

Two variations of dispersion are possible the iodides may be present as such and are dispersed by a mixture of the composite-propellant type (Formula 142) or the iodide may be produced chemically, with several ways available to reach that goal. Shidlovsky cites mixtures of lead powder and iodine donors such as ammonium iodide, iodoform... [Pg.162]

The following chemicals were used as received (from Aldrich unless otherwise noted) 2,6-diaminoanthraquinone, 2,5-dichloro-p-phenylenediamine, 2,6-diamino-5-nitropyrimidine, 2,3,5,6-tetra-methyl phenylenediamine, 2,6-diamino-8-purinol hemisulfate monohydrate, adenine (Chemalog Chemical Dynamics Corp.), 1,9-diamino-nonane, 4,4 -diaminodiphenyl sulfon (Fluka AG), 4,4 -methylene-dianiline, tetraphenyl phosphonium iodide, tetrabutyl ammonium iodide, tetramethyl ammonium bromide, dibenzo-l8-crown-6, 15-crown-5, triphenylantimony dichloride and triethylamine (Eastman Kodak Co.). [Pg.78]

Speciated Components Little information is available for RMs with respect to the chemical forms or species in which elements occur. In the first approximation, bioavaila-ble, extractable, or leachable levels of elements are of interest. Secondly, at a higher degree of sophistication, data on the levels of the actual species or inorganic moieties such as nitrate, ammonium, phosphate, bromide, bromate, iodide, iodate, and molecular species of which the elements are constituents would be of relevance to those conducting mechanistic and speciation research. Reference materials that are certified for extractable elemental concentrations are not available to monitor the usual procedures in soil science based on extraction. [Pg.286]

When iodine is dissolved in hydriodic acid or a soln. of a metallic iodide, there is much evidence of chemical combination, with the formation of a periodide. A. Baudrimont objected to the polyiodide hypothesis of the increased solubility of iodine in soln. of potassium iodide, because he found that an extraction with carbon disulphide removed the iodine from the soln. but S. M. Jorgensen showed that this solvent failed to remove the iodine from an alcoholic soln. of potassium iodide and iodine in the proportion KI I2, and an alcoholic soln. of potassium iodide decolorized a soln. of iodine in carbon disulphide. The hypothesis seemed more probable when, in 1877, G. S. Johnson isolated cubic crystals of a substance with the empirical formula KI3 by the slow evaporation of an aqueous-alcoholic soln. of iodine and potassium iodide over sulphuric acid. There is also evidence of the formation of analogous compounds with the other halides. The perhalides or poly halides—usually polyiodides—are products of the additive combination of the metal halides, or the halides of other radicles with the halogen, so. that the positive acidic radicle consists of several halogen atoms. The polyiodides have been investigated more than the other polyhalides. The additive products have often a definite physical form, and definite physical properties. J. J. Berzelius appears to have made the first polyiodide—which he called ammonium bin-iodide A. Geuther called these compounds poly-iodides and S. M. Jorgensen, super-iodides. They have been classified 1 as... [Pg.233]

Maruoka and coworkers also investigated the substantial reactivity enhancement of N-spiro chiral quaternary ammonium salt and simplification of its structure, the aim being to establish a truly practical method for the asymmetric synthesis of a-amino acids and their derivatives. As ultrasonic irradiation produces homogenization (i.e., very fine emulsions), it greatly increases the reactive interfacial area, which may in turn deliver a substantial rate acceleration in the liquid-liquid phase-transfer reactions. Indeed, sonication of the reaction mixture of 2, methyl iodide and (S,S)-lc (1 mol%) in toluene-50% KOH aqueous solution at 0 °C for 1 h gave rise to the corresponding alkylation product in 63% yield with 88% ee. Hence, the reaction was speeded up markedly, and the chemical yield and enantioselectivity were comparable with those of the reaction with simple stirring (0°C for 8h 64%, 90% ee) (Scheme 5.5) [10]. [Pg.74]

Analogical molecular structure is possessed by other simple compounds such as potassium iodide, ammonium chloride, sodium hydroxide, barium nitrate, ammonium acetate and so on. In all these compounds there is a transfer of one or several electrons from one element to the other, positive and negative ions being thus formed, that are hold together in a crystal by electrostatic attraction. A bond of this kind is no genuine chemical bond in tbe correct meaning of the term, but is just,a result of Coulomb forces of attraction between opposite charges. [Pg.14]


See other pages where Chemicals ammonium iodide is mentioned: [Pg.289]    [Pg.12]    [Pg.4828]    [Pg.5419]    [Pg.5495]    [Pg.2]    [Pg.331]    [Pg.182]    [Pg.253]    [Pg.416]    [Pg.120]    [Pg.18]    [Pg.19]    [Pg.44]    [Pg.457]    [Pg.202]    [Pg.510]    [Pg.392]    [Pg.206]    [Pg.202]    [Pg.184]    [Pg.5]    [Pg.672]    [Pg.1504]    [Pg.303]    [Pg.83]    [Pg.85]    [Pg.272]    [Pg.602]    [Pg.603]    [Pg.611]    [Pg.818]    [Pg.193]    [Pg.2369]    [Pg.155]    [Pg.216]   
See also in sourсe #XX -- [ Pg.223 ]




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Ammonium iodid

Ammonium iodide

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