Raleigh equation

For systems of high (above approximately 3.0) constant relative volatility the Raleigh equation can be expressed ... 

The usual Raleigh Equation form [130] is for the conditions of a binary simple differential distillation (no trays or packing), no reflux, but with constant boilup. 

After this reflux runs down the column the desired lighter components leave, and a desired residual composition is left, following the Raleigh equation to express the material balance. 

For a batch differential distillation where no reflux is used, there is only boilup of a mixture of the desired lighter component, which leaves the kettle, and a desired residual bottoms composition is left in the kettle. This type of distillation follows the Raleigh equation to express the material balance. However, while simple, not having tower packing or trays or reflux does not offer many industrial applications due to the low purities and low yields involved. Repeated charges of the distillate back to the kettle and redistilling w411 improve overhead purity. 

In the application of the Raleigh equation to contaminated sites, complications due to the heterogeneity of the system have been addressed (Abe and Hunkeler 2006). Detailed analysis has revealed systematic problems that could result in underestimation of first-order rates, and procedures for evaluating these were provided. 

Abe Y, D Hunkeler (2006) Does the Raleigh equation apply to evaluate field isotope data in contaminant hydrogeology Environ Sci Technol 40 1588-1596. 

On the basis of the Raleigh equation von Weber [138] developed a diagram from which the concentration of the liquid in the still pot after distilling a charge B down to a residue B-, can be read off for ideal mixtures if x is known. A method of calculating the stepwise countercurrent distillation of ternary systems was evolved by Vogel-pohl [139]. A mathematical model was constructed by Domenech et al. [139a]. A... 

A process that is closely related to sinple batch distillation is differential condensation fTreybal. 19801. In this process vapor is slowly condensed and the condensate liquid is rapidly withdrawn. A derivation similar to the derivation of the Raleigh equation for a binary system gives. 

Cl. For a binary, multistage batch distillation with constant prove that the mass balances over the entire batch period and the Raleigh equation give identical results. 

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