A natural gas stream $(100$kmo$\frac{l}{h})$ contains $98$mol$\%$ methane $(C{H}_4)$ and $2$mol$\%$ hydrogen

sulfide $(H_2(S)).H_{2}S$ is a highly toxic gas. The concentration of $H_{2}S$ in the natural gas stream must

be reduced to $0\mathrm{.}03$mol$\%H_{2}S$ before the natural gas can be used as a fuel or chemical feedstock.

A process engineer recommends that the separation be carried out in a single stage absorber with

water as a solvent. The absorber operates at $5$atm and $40C.($a$)$ Estimate the required water

flow rate $(kmo\frac{l}{h}),($b$)$ Do you think this is a good method to get $H_{2}S$ out of natural gas?

Redo the problem with the following scenarios:

a$)$ What if the temperature was $20C?$ Is this better or worse performance than $40C?$

Explain why.

b$)$ What if you assume that methane is insoluble in water, ie$,x_m=0?$ and $\{$:$P=5(atm)).$

Do you think this is a good assumption? Explain why or why not.

c$)$ What if you assume water does not vaporize $($ie$,\{$:$y_w=0)?$ and $\{$:$P=5(atm)).$ Do you

think this is a good assumption? Explain why or why not.