Aggregation batch reactor

Segregated flow Occurs when all molecules that enter together also leave together. A state of aggregation is associated with every RTD. Each aggregate of molecules reacts independently of every other aggregate thus, as an individual batch reactor. 

Batch Reactor. Let the batch reactor be filled with a macrofluid containing reactant A. Since each aggregate or packet of macrofluid acts as its own little batch reactor, conversion is the same in all aggregates and is in fact identical to what would be obtained with a microfluid. Thus for batch operations the degree of segregation does not affect conversion or product distribution. 

Mixed Flow Reactor-Macrofluid. When a macrofluid enters a mixed flow reactor, the reactant concentration in an aggregate does not drop immediately to a low value but decreases in the same way as it would in a batch reactor. Thus a molecule in a macrofluid does not lose its identity, its past history is not unknown, and its age can be estimated by examining its neighboring molecules. 

FIGURE 6 Solution to the difFerential equation for a batch reactor with aggregation (i.e., equation (6.132)). (a) Variation in [Pg.242]

The ratio (1 /v) is the volume of mixture in the reactor divided by the volume of mixture fed to the reactor per unit time and is called the space time, t. The inverse of the space time is called the space velocity. In each case, the conditions for the volume of the feed must be specified temperature, pressure (in the case of a gas), and state of aggregation (liquid or gas). Space velocity and space time should be used in preference to contact time or holding time since there is no unique residence time in the CSTR (see below). Why develop this terminology Consider a batch reactor. The material balance on a batch reactor can be written [from Equation (3.2.1)] ... 

Catalytic particles of Ru02 (H20)y have been used in a slurry batch reactor to promote, under sonication (20 kHz), the reaction of hexacyanoferrate (III) to hexacyanoferrate (II) by thiosulfate ions7 The ultrasonic rate enhancement appears to be largely associated with the dispersive action of ultrasound on the aggregate particle of Ru02 (H20)y. 

The normally accepted state of a liquid or gas is that of a microfluid, and all previous discussions on homogeneous reactions have been based on the assumption. Let us now consider a single reacting macrofluid being processed in turn in batch, plug flow, and mixed flow reactors, and let us see how this state of aggregation can result in behavior different from that of a microfluid. 

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