Question

Glucose (C₆H₁₂O₆) is converted by yeast into ethanol or propenoic acid (aka acrylic acid) by the following two reactions

C₆H₁₂O₆ à 2 C₂H₅OH + 2 CO₂                            (rxn 1)

C₆H₁₂O₆ à 2 C₂H₃CO₂H + 2 H₂O                           (rxn 2)

Initially an enzymatic reactor is filled with 5700 kg of an aqueous solution of 12 wt% glucose. During the conversion 175.1 kg of carbon dioxide are produced and 133 kg of glucose is left in the reactor after the reactions are complete. Assume that no other reactions are possible, the CO₂ exits as a vapor, and use the approximate molar masses given in the table to determine the:

Species	Molar Mass
glucose	180
ethanol	46
propenoic acid	72
carbon dioxide	44
water	18

     a) kg-mols (aka kmols) of glucose initially present

      b) kmols of glucose converted

      c) kmols of carbon dioxide produced

      d) extent of reaction for reaction 1 in kmols

      e) extent of reaction for reaction 2 in kmols

      f) mole percent of propenoic acid in the product solution

      g) mole percent of ethanol in the product solution

      h) mass percent of propenoic acid in the product solution

Answer 1

Mole=weight/molar mass

Mole % of I = mole of I/(total nber of mole)×100

Mole balance is done according to stoichiometric coefficient of reactant and product.

Page 2

Page 3

a )moles of glucose present initially=3.8kmol

b)Mole of glucose converted=3.06 kmol

c) mole of CO2 formed=3.975 kmol

d)extent of reaction 1= 1.9875 kmol

e) extent of reaction 2= 1.0725 kmol

f) mole % of propanoic acid=50%

g) mole% of ethanol= 50%

h)wt% of propanoic acid= 80%

Hope this will be helpful