[albatal]

Please help me answer these 2 questions!

Question 1
Tamoxifen is a drug that inhibits the growth of breast-cancer cells and is administered in tablet form. In the manufacturing process, a finely ground powder contains tamoxifen (TAM) and two inactive fillers—lactose monohydrate (LAC) and corn starch (CS). The powder is mixed with a stream containing dilute suspended solid particles of polyvinylpyrrolidone (PVP) binder in water. The PVP binder keeps the tablets from easily crumbling. The slurry leaving the mixer goes to a dryer, in which 94.2% of the water fed into the process is vaporized. The wet powder leaving the dryer contains 8.80 wt% TAM, 66.8% LAC, 21.4% CS, 2.00% PVP, and 1.00% water. The wet solid is moulded into tablets, whereas the water vapour leaving the drier is condensed and recycled to be mixed a concentrated mixture of PVP-water suspension to make the stream of dilute PVP-water suspension used in the process. To produce a hundred thousand tablets, 17.13 kg of wet powder is required.
a) Taking a basis of 100,000 tablets produced/min, draw and label a block flow diagram, labelling mass flow rates of individual components.
b) Carry out a degree-of-freedom analysis of the overall process.
c) Calculate the mass flow rates and compositions of the streams that must enter the mixer to make 100,000 tablets/min.
d) Calculate the mass flow rate and composition of concentrated suspension of PVP-water mixture.
e) In part (a) was it necessary to label the stream between the mixer and the dryer? Under what circumstances will it be necessary?
f) Taking a basis of 100 kg/min of wet powder determine the mass fractions of the stream components in the powder fed to the mixer and verify that they match your solution to Part (c). (NOTE: this is to independently validate your answers)
g) Suppose you did Part (f) before Part (c), and re-labelled the powder feed to the mixer on the flowchart of Part (a) with an unknown total mass flow rate ( ̇m1 ) and the three now known mass fractions. (Sketch the resulting flowchart.) Do a degree-of-freedom analysis again and compare the similarities and differences with the DOF analysis in Part (b).

Question 2
Acrolein (C3H4O) is a specialty chemical intermediate used in the manufacture of acrylic acid (C3H4O2) and the synthesis of methionine, an essential amino acid. It is generated via the catalytic oxidation of propylene with air in the presence of steam at a temperature in the range 350–450°C.
C3H6(g) + O2(g) --> C3H4O (g) + H2O (g)
C3H6(g) + 3/2 O2(g) --> C3H4O2 (g) + H2O (g)
The molar ratios of propylene to oxygen to steam in the fresh feed to the reactor are 10:20:6.5. The fresh feed is mixed with a recycle stream from the condenser to make up the reactor feed stream. To meet the stoichiometric requirements of the process and remain outside of the flammable zone, the oxygen concentration entering the reactor is maintained at 14.0 mole%. Complete conversion of propylene is achieved in the reactor and for every mole of acrylic acid produced, 9 moles of acrolein is produced. The reactor products are sent to an absorber where liquid water recycled from the distillation column is added to absorb the acrylic acid. The liquid product stream leaving the absorber contains all the acrylic acid and half of the water entering the absorber. The vapour stream leaving the absorber contains all of the acrolein, oxygen and nitrogen entering the absorber and the remaining water vapour. The vapour stream is sent to a condenser where all the water vapour and acrolein is condensed, and oxygen and nitrogen leave as the overhead product. A fraction (Zp) of the condenser overhead stream is purged whereas the rest is recycled to be mixed with the fresh feed stream. The condensate from the condenser is sent to a distillation column where the overhead product contains essentially all of the acrolein entering the column. The overhead product contains 97 mol% acrolein and 3 mol% water. The bottoms product is essentially pure water and is recycled to the absorber.
(a) Draw and label a block flow diagram for the process described in this problem.
(b) Taking a basis of 100 kmol/h of fresh feed stream, calculate the molar flow rates and compositions of the purge stream, acrolein product stream and acrylic acid product stream.
(c) Calculate the fraction of the condenser overhead stream that is purged (Zp).
(d) Calculate the rate of liquid water recycled from the distillation column into the absorber.
(e) In your own words describe the function of each operation in this process and some of the assumptions that may have been made to simplify the mass balances compared to the real world operation.

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