Separation factor, single stage

The equihbrium constant for this reaction is ca 1.022 at 100°C. The B concentrates in the Hquid phase (23). However, the vapor phase contains ca 40% undissociated complex, which lowers the effective single-stage separation factor to ca 1.014. 

Operational Factors In industrial use, peiwaporation is a continuous-flow single-stage process. Multistage cascade devices are unusual. Peiwaporation is usually an adjunct separation, occasionally a principal one. It is used either to break an azeotrope or to concentrate a minor component. Large stand-alone uses may develop in areas... 

Oxygen-Nitrogen Because of higher solubility, in many polymers, O2 is faster than N2 by a factor of 5. Water is much faster still. Since simple industrial single-stage air compressors provide sufficient pressure to drive an air-separating membrane, moderate purity N2 (95-99.5%) may be produced in low to moderate quantities quite... 

The purity of the final product in a single-stage (ultra-short) column is defined through the separation factor calculated as ... 

The primed or unprimed symbols refer to isotope fractions. The single stage separation factor for infinitesimal product removal (yi/zj 0), (rj)0, is given the symbol a . The i s index the stage number. Most often a is close to unity and it is convenient to define the isotope enrichment factor (the single stage enrichment factor), e, between the i th and (i + l) th stage... 

We now appreciate the reasons for the high cost of enriched uranium. The single stage separation factors are low, as is the natural abundance. This leads inexorably... 

This not only shows how the extent of extraction varies with phase ratio at a constant distribution ratio, but also how varying the phase ratio affects the relative purity of the product. Increasing the phase ratio by a factor of 100 nearly doubles the recovery, but drops the relative purity by a factor of over 25. Note that, in a single stage, it is not possible to achieve both high recovery and a high degree of separation simultaneously. Also,... 

To attain a sufficiently high degree of separation, multiplication of the single stage separation factor is needed. This can only be accomplished by providing circulation of the separated substances. With this approach most of the enriched mixture is returned to the column. 

The relationship between the separation hictor and the enrichment ratio was calculated (Figure-6). As the CO separation factor of Na-LSX at 2I3K is 1.1, it is predicted that the enrichment ratio for a single stage of this VPSA will be 2.5. 

The elementary single stage separation factor a for a two component system is defined as... 

The multiplicative process combines the waste of the i + 1 th stage with the product of the 1 — 1 th stage to form the feed of stage i. The overall separation achieved in the cascade S is defined similarly to the single stage factor... 

The overall separation depends on the single stage separation factor, the number of separating elements, and design and operating characteristics of the cascade. Equations 5-8 are insufficient to determine all the variables. It is instructive to consider three types of cascades the minimum stage cascade, the minimum reflux cascade, and the ideal cascade. The material balance equations from the i + 1 th stage to the product of the cascade lead to... 

The single stage separation factor determines the concentration change across each stage... 

The domain of the search for an improved separation process was defined by certain criteria (a) isotopic fractionation should be achieved by means of a two-phase, chemical exchange reaction which was amenable to countercurrent operation in a multistage contactor at ambient temperature and pressure (b) the single-stage isotopic fractionation factor for the reaction should be appreciably larger than that for the distillation of Me20 BF3 (c) the molecular species in each process stream should be thermally refluxable—i,e, convertible from one species to the other by the addition or removal of heat alone (d) process materials should be more stable with respect to irreversible decomposition than those used in the (CH3)20 process and (e) the chemical form of the product should permit a ready, quantitative conversion of the separated isotopes to the elemental state. 

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