## How do you calculate relative volatility?

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Strictly, the relative volatility is the ratio of K factors for the components, where for each component, i, Ki = yi/xi. For ideal components, K1/K2 = P1/P2.

**What does Fenske equation determine?**

The Fenske equation in continuous fractional distillation is an equation used for calculating the minimum number of theoretical plates required for the separation of a binary feed stream by a fractionation column that is being operated at total reflux (i.e., which means that no overhead product distillate is being …

**What is Gilliland equation?**

An empirical equation used to estimate the number of stages required in a distillation column. It uses the minimum number of stages as well as minimum and actual reflux ratios in the calculation. It is named after American chemical engineer Edwin Gilliland (… …

### What is Alpha in Fenske equation?

αt. = relative volatility of light key to heavy key at top of column. αb. = relative volatility of light key to heavy key at bottom of column. The above Fenske equation can be modified for use in the total reflux distillation of multi-component feeds.

**What relative volatility tells us?**

Relative volatility is a measure comparing the vapor pressures of the components in a liquid mixture of chemicals. This quantity is widely used in designing large industrial distillation processes.

**What is the Fenske-Underwood-Gilliland method?**

The mathematical model of the column is obtained by performing a total mass balance and partial mass balances to component “ i .” The Fenske-Underwood-Gilliland method is used to find the functional relationship between the compositions of the bottom and the dome of the column.

#### What is Gilliland correlation?

[gə′lil·ənd ‚kä·rə‚lā·shən] (chemical engineering) Approximation method for distillation-column calculations; correlates reflux ratio and number of plates for the column as functions of minimum reflux and minimum plates.

**What is the significance of the relative volatility α in a distillation process?**

VLE: Relative Volatility. In order to separate a binary mixture using distillation process, there must be a differences in volatilities of the components. The greater the difference, the easier it is to do so. A measure for this is termed the relative volatility.

**What is the Fenske equation in continuous fractional distillation?**

Fenske equation. The Fenske equation in continuous fractional distillation is an equation used for calculating the minimum number of theoretical plates required for the separation of a binary feed stream by a fractionation column that is being operated at total reflux (i.e., which means that no overhead product distillate is being withdrawn from…

## What is the origin of the Fenske equation?

The equation was derived in 1932 by Merrell Fenske, a professor who served as the head of the chemical engineering department at the Pennsylvania State University from 1959 to 1969.

**What is relative volatility of a mixture?**

For a liquid mixture of two components (called a binary mixture) at a given temperature and pressure, the relative volatility is defined as When their liquid concentrations are equal, more volatile components have higher vapor pressures than less volatile components.

**What happens when the volatilities of both components are equal?**

When the volatilities of both key components are equal, = 1 and separation of the two by distillation would be impossible under the given conditions because the compositions of the liquid and the vapor phase are the same ( azeotrope ). As the value of increases above 1, separation by distillation becomes progressively easier.