Rayleigh distillation process

Assuming a Rayleigh distillation process and bulk eclogite/fluid D s for 3 GPa without rutile from Table 2... 

An idealized illustration of the differences between the 5 0 of condensate and vapor as a function of the fraction of the remaining water during the Rayleigh distillation process. Envision a cloud that forms at 20 and remains a closed system except for water that rains out as it cools from 20 °C to — 20 °C. The equilibrium fractionation factor is temperature dependent, 9%o at 20 °C and I I %o at 0°C. Modified from Dansgaard (1965). 

Zhu (2000) used the modeling results to calculate travel time. The initial well has a radiocarbon activity of 72.9% modern, and final well 7%. Precipitation of calcite results in isotopic fractionation, which netpath treats as a Rayleigh distillation process (Plummer et al., 1991 Wigley et al., 1978). After the mass balance calculations, there... 

There are other effects to consider. They are temperature, altitude, and latitude. The above correlation confirms that atmospheric precipitation follows a Rayleigh distillation process at... 

Differential condensation in which the liquid separates from the vapour from which it has condensed. This process is analogous to differential, or Rayleigh, distillation, and the condensation curve can be calculated using methods similar to those for determining the change in composition in differential distillation see Volume 2, Chapter 11. 

Rayleigh distillation is a process in which the condensate is immediately removed from the vapor after formation (by fallout of rain and snow in the meteorological case) and leads to a higher... 

The compositional relations discussed above are explained by Rayleigh s distillation process (Rayleigh, 1896), choosing a suitable partition coefficient for the component of interest—i.e., for component An, we can write... 

Earlier in this chapter, we discussed isotopic fractionation during evaporation. Under appropriate conditions, where the condensed phase remains isotopically well mixed and the gas phase is removed from the system to prevent back reaction, Rayleigh distillation will occur (Box 7.2), resulting in a condensed phase that is isotopically heavy relative to the starting composition (Fig. 7.9). Isotopic fractionation can occur during both condensation and evaporation, as demonstrated by experiments (Richter el al., 2002). But it is not necessary that isotopes fractionate during evaporation or condensation. It depends on the details of the process. If evaporation occurs into a gas phase that is sufficiently dense, back reactions between gas and liquid can reduce the isotopic fractionation to near the equilibrium value, which is very small. For example, sulfur in chondrules does not show the isotopic fractionation (Tachibana and Huss, 2005) expected during evaporation from a liquid. Also, evaporation from a solid does not produce isotopic fractionation in the solid because diffusion is much too slow to equilibrate the few layers of surface atoms that are fractionated with the bulk of the material. 

We have seen that elements can be separated based on their volatility, either through gas-solid or gas-liquid reactions. There are many types of reactions that form a continuum between equilibrium condensation (or its inverse, evaporation) on the one hand and purely kinetically controlled reactions, such as Rayleigh distillation, on the other. In some cases, isotopic fractionation can assist in identifying the processes involved. 

Since the Rayleigh distillation is likely to be the most common fractionation process in noble gas geochemistry, we will give some quantitative discussion of this process next. Suppose atoms (or isotopes) and / are escaping at a rate k and kj from a reservoir which contains , and rij numbers of the atoms, we have... 

Even in the first publications concerning the copolymerization theory [11, 12] their authors noticed a certain similarity between the processes of copolymerization and distillation of binary liquid mixtures since both of them are described by the same Lord Rayleigh s equations. The origin of the term azeotropic copolymerization comes just from this similarity, when the copolymer composition coincides with monomer feed composition and does not drift with conversion. Many years later the formal similarity in the mathematical description of copolymerization and distillation processes was used again in [13], the authors of which, for the first time, classified the processes of terpolymerization from the viewpoint of their dynamics. The principles on which such a classification for any monomer number m is based are presented in Sect. 5, where there is also demonstrated how these principles can be used for the copolymerization when m = 3 and m = 4. 

This gradual enrichment of the TDC with C results from the escape of the dissolved CO 2, a process similar to a Rayleigh distillation. 

Equations relating the flow rates and compositions of feed and product streams in differential separation processes, first derived by Lord Rayleigh [Rl] for batch distillation, are often called the Rayleigh distillation equation. We shall derive some of these relationships for type B differential stage separation, using the nomenclature shown in Fig. 12.11. 

Consider the boiling of a liquid mixture in which the vapor that is produced is continually removed. In such a process, which is called a Rayleigh distillation, the concentration of the more volatile component in the liquid will continue to decrease as the boiling proceeds. In fact, this is the simplest type of batch distillation and has been used since antiquity. (Should we consider the earliest distillers of alcohol who used this process to be the first chemical engineers ) For this process the overall rate-of-change form of the mass balance and the rate-of-change form of the mass balance for species i are / ... 

One way to remove a dissolved gas from a liquid is by vaporizing a small amount of the liquid in such a way that the vapor formed is continually withdrawn from the system. This process is known as differential distillation or Rayleigh distillation, as discussed in Sec. 10.1. 

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