# 1.1: Performance Metrics for Separation Processes


$$n_{i,k}^{(F)}$$ = mass or molar flow rate of species $$i$$ entering separator $$k$$ in feed stream (mass time-1 or mol time-1)

$$n_{i,k}^{(1)}$$ = mass or molar flow rate of species $$i$$ leaving separator $$k$$ in first product stream (mass time-1 or mol time-1)

$$n_{i,k}^{(2)}$$ = mass or molar flow rate of species $$i$$ leaving separator $$k$$ in second product stream (mass time-1 or mol time-1)

$${\rm SF}_{i,k}$$ = split fraction for species $$i$$ in separator $$k$$ (dimensionless)

$${\rm SR}_{i,k}$$ = split ratio for species $$i$$ in separator $$k$$ (dimensionless)

$\tag{1.1} {\rm SF}_{i,k} = n_{i,k}^{(1)} / n_{i,k}^{(F)}$

$\tag{1.2} {\rm SR}_{i,k} = n_{i,k}^{(1)}/n_{i,k}^{(2)} = {\rm SF}_{i,k} / (1-{\rm SF}_{i,k})$

## Example

For the process below, compute the split fraction and the split ratio for $$i C_5 H_{12}$$. Designate the overhead stream as product stream 1.

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