Potassium nitrate, crystallization

The length of c can be obtained very simply from this photograph by measuring the distance y of any layer line from the equator if the camera radius is r, then rjy is tan c is then given by wA/ccs , n being the number of the layer line selected (the equator having n = 0). For the potassium nitrate crystal, c is G-45 A. If a flat film is used instead of a cylindrical film, the layer lines are shown, not as straight lines... 

The solubility diagrams of several species are shown in Fig. 2, and these illustrate the importance of solubility behavior in the selection of the mode of crystallization. For example, consider the differences between potassium nitrate and sodium chloride The solubility of potassium nitrate is strongly influenced by the system temperature, whereas the opposite is true for sodium chloride. As a consequence, (1) a high yield of potassium nitrate crystals can be obtained by cooling a saturated feed solution,... 

Potassium nitrate crystals have a density of 2.11 x 1(T12 g//um3, which allows for the determination of the estimated crystal numbers on each sieve in Table II. A cumulative number distribution, N(L), and a cumulative number fraction distribution, F(L), can be calculated using methods similar to those for calculating M(L) and W(L). 

Spread crystals on Oat surface and allow to dry. The potassium nitrate crystals are now reacfy for use. 

After storage in a damp atmosphere efflorescence of potassium nitrate crystals may occur. This can be detected under the microscope. Except for such efflorescence there is no tendency for the ingredients to segregate. If stored in contact with metals some reduction of the nitrate to nitrite may occur. 

Heat the filtrate from the potassium nitrate crystals to boiling and evaporate it to about two-thirds its original volume. (1) What is the compound that separates during the boiling Filter the hot solution rapidly. Save the filtrate. Press the crystals between filter papers. Examine them with a magnifying glass. (2) Do they resemble the crystals of potassium nitrate in appearance (3) Upon what fact does the separation of potassium nitrate from the other three substances in solution depend Examine the crystals that are deposited from the filtrate when it cools. (4) What are they ... 

The anticaking properties of acid magenta and other dyestuffs have been described by Whetstone, who recommends an 0.10% coverage of ammonium nitrate crystals during the crystallization process from solution as the preferred method. Butchart claims the addition of certain water-soluble anthraquinone derivatives to solutions or to wet crystals to promote free-flowing low setting tendencies in potassium nitrate crystals. Similar improvements are claimed by Marti for the addition of 2-3 % CuO or CuaO to ammonium nitrate. 

Potassium chloride and a stoichiometric quantity of chilled 60%-70% nitric acid are fed into the first reactor at 5°-10 C. Recycled brine and solvent are added to the reactor. In the presence of the solvent, the reaction goes almost to completion. During the process potassium nitrate crystallizes from solution. Solid product is separated in a decanter and directed to a centrifuge and dryer. It can be sold in the powder form or melted and prilled. 

Place the potassium nitrate crystals on the screen. Rub the material back and forth against the screen mesh with the wooden block until the nitrate is granulated into a powder. 

Note it may be necessary to crush the potassium nitrate crystals and sulfur to obtain an accurate measure in tablespoon. 

Helt, J.E. and Larson, M.A., 1977. Effects of temperature on the crystallization of potassium nitrate by direct measurement of super-saturation. American Institution of Chemical Engineers Journal, 23(6), 822. 

To a solution of 13.5 g of 5-(2-chlorophenyl)-3H-1,4-benzodiazepin-2(1 H)-one in 60 ml of concentrated sulfuric acid, a solution of 5.5 g of potassium nitrate in 20 ml concentrated sulfuric acid was added dropwise. The solution then was heated in a bath at 45° to 50°C for Th hours, cooled and poured on ice. After neutralizing with ammonia, the formed precipitate was filtered off and boiled with ethanol. A small amount of white insoluble material was then filtered off. The alcoholic solution on concentration yielded crystals of 7-nitro-5-(2-chlorophenyl)-3H-1,4-benzodiazepin-2(1H)-one which, after recrystallization from dichloromethane, melted at 238° to 240°C. 

In particular, if we raise the temperature, there will occur some change which will give rise to absorption of heat. If a saturated solution of potassium nitrate is in equilibrium with crystals of solid salt at a particular temperature, and if we now raise the temperature, a change must occur which absorbs heat and so tends to cool the system. This is the dissolution of more solid, because the heat of solution is positive, that is, heat is absorbed when salt goes into solution. But if we have a saturated solution of calcium sulphate, there will occur a precipitation of solid on warming, because the heat of solution is negative, and heat is absorbed when salt comes out of solution. 

The potassium nitrate shall be odorless, and the crystals white in color... 

Fujiwara, M., Fukui, M. and Tanimoto, Y. (1999) Magnetic orientation of benzophenone crystals in fields up to 80.0 kOe./. Phys. Chem. B, 102,2627-2630. Fujiwara, M., Tokunaga, R. and Tanimoto, Y. (1998) Crystal growth of potassium nitrate in a magnetic field of 80kOe./. Phys. Chem. B, 102, 5996-5998. 

When a compound that can form several modifications crystallizes, first a modification may form that is thermodynamically unstable under the given conditions afterwards it converts to the more stable form (Ostwald step rule). Selenium is an example when elemental selenium forms by a chemical reaction in solution, it precipitates in a red modification that consists of Se8 molecules this then converts slowly into the stable, gray form that consists of polymeric chain molecules. Potassium nitrate is another example at room temperature J3-KN03 is stable, but above 128 °C a-KNOs is stable. From an aqueous solution at room temperature a-KN03 crystallizes first, then, after a short while or when triggered by the slightest mechanical stress, it transforms to )3-KN03. 

Circulating liquor Production of uniform crystals (smaller size than circulating magma). High throughputs. Gypsum, inorganic salts, sodium and potassium nitrates, silver nitrates... 

A disadvantage of the conventional precipitation method in which the supersaturation was allowed to decrease during the reactions, was that different calcium phosphate phases could form and subsequently dissolve during the course of the reactions. In the present work, the constant composition method was used to investigate the influence of sodium chloride, potassium chloride, and potassium nitrate, as background electrolyte upon the rate of crystallization of HAP in solutions supersaturated only with respect to this phase. These experiments were made in solutions containing totaj... 

The ultra-micro-hardness of inorganic and organic salts has been measured for 15 substances. These are products usually produced in industrial crystallization. The hardness-force-dependency was examined and data are compared to those from literature. In the case of potassium nitrate a strong direction dependency of the hardness was observed. Also effects of impurities in the crystal lattice were analysed. In the end an attempt has been introduced to calculate the hardness of crystals from a physical model. 

In the case of potassium nitrate the Vickers hardness indentations have not a quadratic shape. This is due to a direction dependent hardness in the crystal lattice of this material. The direction dependency can be explained with an anisotropic effect in the lat-... 

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