Question

Sulfur dioxide may be converted to SO3, which has many uses, including for the production of H2SO4 and sulfonation of detergents. A gas stream having the composition shown below is to be passed through a two stage converter (i.e. two separate reactors). The fractional conversion (single pass) of SO2 to SO3 in the first stage is 0.75 and in the second stage it is 0.65. To boost the overall conversion to 0.95, some of the exit gas from stage 2 is recycled back to the inlet of stage 2. How much must be recycled per 100 mol of inlet gas (F). Ignore any effects of temperature on the conversion. So, 10.0% O, 9.0% N 81.0% Ag mol)

Answer 1

Answers: the Reaction as follows: Soz - Sozi For 100 moles of leed, forstage: Input moles of so, = lomoles single pass Conversion - 0.75 Moles of So, conreacted = (1-0.75) lomoles. - 2.5 moles. For Stage : 2 Input anoles of so, = 2.5 moles. Single pass conversion - 0.65. Moles & So, unreacted - (1-0.65) 2.5 moles - 0.875 moles

the overall Conversion for the process is Reactont Input - reactont output Reactant Input = 0.95 -0.95 lomol - 2.5 mol & (2.5 +0.875) mol-R lomol (2.5 40.875 ) mol = 0.95 0.757 3.375 mol-R 3.375 mol 3.375-R-3.375 (0.95 -0.75). 3.375-R = 0.675 mol RF (3.375 – 0. 675) nol = 2.7 mol Therefore, the moles of Recycle is 2.7 moles.