Question

Please solve for only problem 2. The first problem is needed for the 2nd one. Please show all work and thank you.

1.) Oxidative dehydrogenation of ethane is the conversion of ethane with oxygen to yield ethylene and water. It is a cleaner and more efficient alternative to the widely used steam cracking process for ethylene production from ethane.

a. Write down the (balanced) reaction equation, and list (separately) the stoichiometric coefficients for all reactants and products. Assuming that you start with a mixture of 75vol% air and 25vol% ethane, what is the limiting reactant?      

b. In addition to oxidative dehydrogenation, ethane/oxygen mixtures can also undergo partial oxidation, i.e. the formation of synthesis gas (CO and H2), as well as total oxidation, i.e. complete combustion of ethane towards CO2 and water. Write down the reaction equations for both reactions. Assuming that the mixture in problem 1 undergoes partial or total oxidation, which is the limiting reactant in each case?

2.) Hydrogen is of great interest as a feed for fuel cells. However, in order to use the hydrogen content of the syngas produced via partial oxidation of ethane, one would need to remove virtually all the CO from the mixture since CO is a strong poison for most fuel cells. This could be done through addition of steam in order to convert the CO via the so-called ‘water gas shift’ reaction (WGS: CO + H2O = CO2 + H2). Assuming a feed flow of 100 L/min of the same feed mixture as in problem 1, and furthermore assuming that the partial oxidation reaction goes to completion, how much steam needs to be added in order to completely convert the CO? (Assume stoichiometric conversion via WGS.) What is the composition of the effluent stream (in molar fractions)?

Answer 1

DEAR STUDENT, NOTE THAT VOLUME PERCENTAGE & MOLE PERCENTAGE ARE SAME & COMPOSITION HAS BEEN CALCULATED ACCORDINGLY . IN CASE OF ANY QUERY FEEL FREE TO CONTACT. I SHALL DEFINITELY TRY TO RESOLVE THEM. THANK YOU.