الفهرس 
LITERATURE SURVEYOnly 14 pages are availabe for public view
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Abstract
The objective of the present work is to develop A new pulsating packed bed contactor, was developed in the present study. The contactor is suitable for conducting diffusion controlled liquid-liquid operations such as; separation of aromatics and aliphatics in the petroleum industry, removal of phenol from wastewater, separation of catalyst from reaction products, and the separation of labile materials, such as antibiotics, .. etc. Pulsed columns have a clear advantage over other mechanical contactors; namely, they consume less power for the same rate of production. To this end, the performance of a pulsed bed contactor in conducting diffusion controlled process was studied by measuring the volumetric mass transfer coefficient for the extraction of acetic acid from toluene - acetic acid mixture by water. This system has been widely used to assess the performance of different extractors.
The following variables were investigated: (i) the density, viscosity and diffusivity of the feed solution (toluene-acetic acid), (ii) the frequency of oscillation, the amplitude of oscillation, (iii) the initial concentration of acetic acid, (iv) the number of layers per each bed (bed height), (v) the packing sphere diameter, bed spacing, flow rate of the dispersed phase (toluene + acetic acid), and (vi) the flow-rate of the continuous phase (water).
It was found that the rate of mass transfer increased by increasing the frequency of oscillation, amplitude of oscillation; initial concentration of acetic acid, continuous phase (water) flow rate, and dispersed phase (toluene) flow rate. Also, the rate of mass transfer was found to be increased with increasing number of layers per bed (bed height) up to bed height of I cm (composed of 2 layers per packed bed), then the increase in bed height decreased the rate of mass transfer. The effect of bed spacing on the rate of mass transfer was found to be insignificant, whereas the rate of mass transfer decreased with increasing the packing sphere diameter. The pulsated multi-packed bed data were correlated by the following dimensionless equation(
d J-{)’ 1 099
Sh = 00142 Se°.33 ReO.3874 Re•O.6287 ReO.7612 _b
m• v d C h
In order to assist in assessing the economic feasibility of the reactor, mechanical power consumed in the pulsating multi-bed column were measured under different conditions. Practical application of the present work in different fields such as pharmaceuticals, chemical, biochemical, petroleum industries, and nuclear fuel reprocessing were noted.