Ammonia description

U S. DOE HAZMAT SPILL CENTER DATABASE 23.17 Dates of Experiments June 29, 1992-July 24, 1992 Chemical(s) Released Chlorine and ammonia Description of Experiments See HF suit tests. 

A suspension of 0.40 mol of sodium amide in 300 ml of liquid ammonia was prepared as described in Chapter II, Exp. 11. To the suspension was added with swirling a mixture of 0.25 mol of CHgCeC-S-Ph (see Chapter IV, Exp. 14) and 40 ml of THE in about 2 min (note 1). Swirling was continued after the addition. Three minutes later (note 1) the stopper with glass tube was placed on the flask. The brown solution was forced through the glass tube and the plastic tube, connected to it under 400 g of finely crushed ice, which was contained in a 3-1 conical flask (see Chapter I, Fig. 3, and accompanying description of this operation). The flask was placed for... 

All other things being equal, the strength of a weak acid increases if it is placed in a solvent that is more basic than water, whereas the strength of a weak base increases if it is placed in a solvent that is more acidic than water. In some cases, however, the opposite effect is observed. For example, the pKb for ammonia is 4.76 in water and 6.40 in the more acidic glacial acetic acid. In contradiction to our expectations, ammonia is a weaker base in the more acidic solvent. A full description of the solvent s effect on a weak acid s piQ or on the pKb of a weak base is beyond the scope of this text. You should be aware, however, that titrations that are not feasible in water may be feasible in a different solvent. 

AMMONIA Raw material Process description Feedstock conversion reaction V012... 

Diacetunamine has been prepared in satisfactory yields by treating a mixture of commercial acetone and calcium chloride with anhydrous ammonia. The preparation from commercial acetone and ammonia is laborious and gives low yields. No yields are given in the older published descriptions of the preparation from mesityl oxide with either aqueous or anhydrous ammonia. The method described here has recently been published. ... 

Eng 20, 470-477 (1919) (Description of ammonia oxidation process beginning with Kuhl-mann s method of 1839 and ending with the cyanamide process at Muscle Shoals) 7) C.L. Parsons, 1EC 11,541 (1919) (Oxidation of ammonia to nitric acid as well as the prepn of nitric acid from Chile saltpeter) 8) F.C. Zeis-berg, ChemMetEng 24, 443-45 (1921) (Manuf of nitric acid from Chilean saltpeter brief description) 9) G.B. Taylor, IEC 26,1217-19 (1922) (Some economic aspects of ammonia oxidation) 10) Ministry of Munitions, Manufacture of Nitric Acid from Nitre and Sulfuric Acid , London (1922) (Book No 7 of Technical Records of Explosives Supply, 1915—1919)... 

Pressure synthesis operations of the duPont Ammonia Corp, including description)... 

A species that bonds to a metal cation to form a complex is known as a ligand. Any species that has a lone pair of electrons has the potential to be a ligand, but in this section, we confine our description to a few of the most common ligands ammonia, compounds derived from ammonia, cyanide, and halides. We describe additional examples in Chapter 20 which addresses the chemistry of the transition metals. 

The simplest type of Lewis acid-base reaction is the combination of a Lewis acid and a Lewis base to form a compound called an adduct. The reaction of ammonia and trimethyl boron is an example. A new bond forms between boron and nitrogen, with both electrons supplied by the lone pair of ammonia (see Figure 21-21. Forming an adduct with ammonia allows boron to use all of its valence orbitals to form covalent bonds. As this occurs, the geometry about the boron atom changes from trigonal planar to tetrahedral, and the hybrid description of the boron valence orbitals changes from s p lo s p ... 

The kinetics of the ammonia synthesis have been discussed as an example of micro-kinetic modeling in Chapter 7. Here we present a brief description of the process, concentrating on how process variables are related to the microscopic details and the optimization of the synthesis. 

GP 1] [R 1] A kinetic model for the oxidation of ammonia was coupled to a hydro-dynamic description and analysis of heat evolution [98], Via regression analysis and adjustment to experimental data, reaction parameters were derived which allow a quantitative description of reaction rates and selectivity for all products trader equilibrium conditions. The predictions of the model fit experimentally derived data well. 

Relatively few descriptions of direct mass spectral analysis of plastics compounds have appeared in the literature [22,37,63,240,243], Additives in PP were thermally desorbed into a heated reservoir inlet for 80 eV EI-MS analysis [240], Analysis of additives in PP compounds via direct thermal desorption ammonia CI-MS has been described [269] and direct mass spectrometric oligomer analysis has been reported [21],... 

Various secondary sources of safety data are now listing this as an explosive. I can find no primaiy source for this classification, which seems very improbable. Simple minded use of many computational hazard prediction procedures would show thermodynamically that this compound, like most lower amines, could hypothetically convert to alkane, ammonia and nitrogen with sufficient energy (about 3 kJ/g) to count as an explosion hazard. This reaction is not known to happen. (Simple minded thermodynamicists would rate this book, or computer, and its reader as a severe hazard in an air environment.) Like other bases, iminobispropylamine certainly sensitises many nitro-explosives to detonation. It is used experimentally to study the effect, which may have found technical exploitation and, garbled, could have led to description of the amine as itself an explosive. 

With respect to the considerations above, research is split into three parts. The first is connected to the kinetic description of the release of ammonia from the biomass as function of temperature. This research employs infrared spectroscopy using a tunable diode laser. Here very small biomass particles are used that are heated up very rapidly in a small reactor, which ensures that transport effects are virtually excluded from the kinetic release effects. Since ammonia is released in very small quantities it is quite hard to detect. Therefore, we first measure CO release, which is easier. In the second part we investigate the propagation of a conversion front in biomass layers. Here we perform experiments and try to establish a modeling approach for the propagation by analytical and numerical approaches. In the third part the gas-phase conversion processes are described in terms of... 

Recently, this view of secondary a-deuterium KIEs has had to be modified in the light of results obtained from several different theoretical calculations which showed that the Ca—H(D) stretching vibration contribution to the isotope effect was much more important than previously thought. The first indication that the original description of secondary a-deuterium KIEs was incorrect was published by Williams (1984), who used the degenerate displacement of methylammonium ion by ammonia (equation (4)) to model the compression effects in enzymatic methyl transfer (SN2) reactions. 

Although the description fulminating is not used and thus confusion with the fulminate not caused, mercury also forms explosive compounds of similar nature. The nitride (ibid.) is the most common and can be formed from the metal and ammonia in some circumstances, causing accidents where mercury manometers are used with ammonia. Halo-hydroxy- and oxy-nitrides can also be involved [3], See METAL FULMINATES, GOLD COMPOUNDS, A-METAL DERIVATIVES, PRECIOUS METAL DERIVATIVES, SILVER COMPOUNDS... 

The above value of k4 1 s for bpy loss from Rh(bpy)3 + may be compared with k4 - 3 s for bpy loss from the formally related Co(bpy)32+ (13,14) Recently obtained results indicate that the rate constant for addition of bpy to Rh(bpy)2(H2O)2 (k 4 s 0.2 x lO Ms"1) is greater than that for the comparable cobalt(II) reaction (13,14) The more-or-less comparable labilities of Rh(bpy)3 T and Co(bpy)3 + are not unexpected in light of data for rates of ammonia loss from the two metal centers which are also available ammonia loss from rhodium(II) is quite rapid (10 s 1 to 10 s l with loss from Rh(NH3)5 H20 + being much faster than from Rh(NH3)4 +, etc ) W t>ut somewhat slower than the comparable process for cobalt(II) (15) Of course, here the relative affinities of the two metals for NH3 are not known and so cannot be taken into account A further reason these comparisons lack great validity is that, although these Co(II) complexes contain 3d metal centers, Co(bpy)3 + and Co(NH3)n + are high-spin complexes i.e. the ground states are (t2g) (eg) whereas 4d species are expected to be low spin, (t2g) (eg)1. Furthermore, as will be seen shortly it is not clear that even "low spin 4d " is an adequate description of the... 

Prior to description of the cycle, it should be noted that ammonia has several important roles in the cell, which include the following ... 

For years, AIChE has sponsored public presentation of actual incident descriptions with accompanying lessons learned. Some of these case histories are contained in the AIChE publications on Ammonia Safety Symposium, Loss Prevention, Chemical Engineering Progress, and Plant Operations Progress. The American Petroleum Institute also publishes a series of booklets on... 

A detailed description of salt mining will be postponed until the next chapter, but it is important to note that soda ash is made from both limestone and salt, the two major raw materials. As outlined in Fig. 5.2, the brine (salt solution) is mixed with ammonia in a large ammonia absorber. A lime kiln, using technology similar to that discussed earlier, serves as the source of carbon dioxide, which is mixed with the salt and ammonia in carbonation towers to form ammonium bicarbonate and finally sodium bicarbonate and ammonium chloride. Filtration separates the less soluble sodium bicarbonate from the ammonium chloride in solution. 

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