Che 201

CHE 201 Tutorial #7

Q1

The reaction between ethylene and hydrogen bromide to form ethyl bromide is carried out in a continuous reactor. The product stream is analyzed and is found to contain 50 mol% C2H5Br and 33.3% HBr. The feed to the reactor contains only ethylene and hydrogen bromide. Calculate the fractional conversion of the limiting reactant and the percentage by which the other reactant is in excess.

Q2

HCl and O2 react to form Cl2 and H2O. Sufficient air (21 mol% O2, 79% N2) is fed to the reactor with 25% excess and the fractional conversion of HCl is 70%. Calculate the mole fractions of the product stream components.

Q3

The following reaction:

[pic]

takes place in a continuous reactor. The feed to the reactor contains 95% methane (CH4) and 5% inert and flows at a rate of 50 mol/h. The product was found to contain 15 mol/h of ethane (C2H6). Find

a. The % conversion of methane.

b. % molar composition of product stream.

Q4

Given that the reaction for fresh feed A and B is

[pic]

carried out in a reactor with recycle, find the desired recycle ratio (moles recycle/moles feed) if in the fresh feed A is 20% in excess. The single pass conversion of B is 60% and the overall conversion of B to products for the overall process is 90%. After the products exit from the reactor, a stream of pure B is separated and forms the recycle.

Q5

Methane and oxygen react in the presence of catalyst to form formaldehyde. In a parallel reaction methane is oxidized to carbon dioxide and water:

[pic]

The feed to the reactor contains equimolar amounts of methane and oxygen. Assume a basis of 100 mol feed/s.

a. Write the material balance equations and determine (if possible) the product molar flow rate.

b. The fractional conversion of methane is 0.9 and the fractional yield of formaldehyde is 0.855. Calculate the molar composition of the reactor output stream and the selectivity of formaldehyde production relative to carbon dioxide production.

Q6...