Mathematical equations for approximation of separation results using the Fuerstenau upgrading curves

Results of separation can be presented as two-parameter graphs. One of many separation plots is the Fuerstenau upgrading curve, which relates recoveries of components in products of separation. It is demonstrated in the paper that there is a great number of mathematical formulas, which can be used for approximation of data plotted as the Fuerstenau curve. It is also shown that a given set of upgrading data can be approximated with a reasonable accuracy using different mathematical formulas as well different sets of data can be approximated with the same formula. A third option is the approximation of the different separation results with different equations. Depending on the approach and equations used for approximation of separation data, different conclusions may be obtained.