Thermal decomposition of ammonium nicotinate

Autor: A. A. Sokolovskii, É. M. Guseinov, V. V. Zarutskii, G. V. Oslyakov, N. M. Kondrat'eva
Rok vydání: 1981
Předmět:
Zdroj: Pharmaceutical Chemistry Journal. 15:749-752
ISSN: 1573-9031
0091-150X
DOI: 10.1007/bf00765391
Popis: In apparatus i, a layer of particles (crystals) of I is loaded from feed bin 3 onto an exchangeable perforated distribution grid 2 to a given height. The air, fed through rotameter 8 heats up in electric heater 9, passes through the grid and sets khe layer of the material into motion. The resistance of the grid and the layer is measured by an inclined micromanometer M~ i0, and the temperature under the grid, in the layer, and at the out~et is measured by chromel-copel thermocouples, whose emf is recorded by KSP-4 potentiometer ii with an accuracy within  In the experiment, perforated grids with a clear opening of 1.6, 4, and 6.6% were used. Compound III formed during the decomposition of I is carried away with the heat carrier, passes through bubbler 6, and is trapped by sulfuric acid in bubbling vessel 7. At the end of the process, the solution was titrated, and the product remaining in the apparatus and entering collector 5 through cyclone 4 was analyzed for the content of II. The apparatus was made of glass, so that the visual observations required to study the hydrodynamics of the process were possible. For a preliminary calculation of the construction parameters of the apparatus, we must determine the dependence of the pressure drop on the stream velocity of the heat carrier and the height of the layer. It is known that the homogeneity of the mobile layer of the particles increases with decrease in their size, but below a certain limit the forces of interaction between the particles increase, which leads to agglomeration and channel formation. We studied the principal characteristics of the mobile layer of I. A microstructural analysis of the semidispersed layer of I showed that the layer consists mainly of aggregates of particles of size 50 to 150 gm (mean size i00 pm). After the thermal decomposition of I, the large aggregates break down, and the mean particle size is 30 pm. The bulk density of dry I (u is equal to 600 kg/m 3, and the specific weight (Yo) is 1770 kg/m 3, The porosity of the mobile layer (Elr) was determined from the formula
Databáze: OpenAIRE
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