Chapter 9, Problem 9.36P

Interpretation Introduction

(a)

Interpretation:

A flowchart of process along with degree of freedom analysis needs to be prepared and molar amounts of all species in product to be calculated.

Concept introduction:

Flow chart is diagrammatic representation of the reaction taking place in the reactor:

The calculation of flowchart is based on the relation

$\text{Input}\text{-}\text{Output}\text{=}\text{Accumulation}$

It helps us to determine the amount of product formed with respect to the amount of reactant fed to the reactor.

Mole fraction $\left(y_i\right)$ of any components given by:

$y_i=\frac{n_i}{\sum n_i}$

Here, $n_i$ is the moles of component $i$ and $\sum n_i$ is the total moles of all the components present in the mixture.

Interpretation Introduction

(b)

Interpretation:

The amount of heat added or removed from the reactor is to be calculated

Concept introduction:

The amount of heat transferred is calculated as follows:

Based on energy conservation

$Q\text{}=\sum _{out}n{\hat{H}}_f-\sum _{in}n{\hat{H}}_i$

Here,

$\sum _{out}n{\hat{H}}_f$ is the heat of formation of product

$\sum _{in}n{\hat{H}}_i$ is the heat of formation of reactant

Enthalpy of reactant and product depends upon the specific heat and the temperature difference.

Interpretation Introduction

(c)

Interpretation:

If the process is considered for biodiesel formation, whether biodiesel is economically viable as compared to petroleum diesel or not needs to be determined.

Concept introduction:

Energy transfer equation,

$Q\text{}=\sum _{out}n{\hat{H}}_i-\sum _{in}n{\hat{H}}_i$

This equation helps to determine the amount of energy generated in product stream with respect to the energy given to the reactor.

Interpretation Introduction

(d)

Interpretation:

For atomic species, the degree of freedomneeds to be calculated.

Concept introduction:

Degree of freedom helps to determine the feasibility of reaction and tells about the number of unknowns in a reaction.

The formula for degree of freedom is given as

Degree of freedom = no. of unknown + no. of chemical reaction − no of independent molecular species − no of independent non-reactive molecular species − no. of equation relating unknown