Introductory Chemometrics Chemical Process Modeling Problem
Group work required; no collaboration between groups. Show
all work to receive credit
Use the data in the spreadsheet to:
1. Derive a multivariable regression equation that uses
the average instantaneous conversion and average batch temperature to determine
end of reaction styrene concentration based on measured styrene results.
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Show the developed equation
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Plot the residuals as a function of styrene concentration
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Use p values, the coefficient of determination, and your residuals
plot to comment on the validity of your styrene end of batch concentration
prediction model
2. Use the Material Safety Data Sheet
for Styrene to find the OSHA 8 hour TWA.
3. Use the Flory-Huggins partial pressure worksheet to determine
the maximum styrene latex concentration allowable under the OSHA 8 hour
TWA guidelines at the end of the stripping process. Assume that the
final butadiene concentration is 500 ppm.
4. Use the regression model developed in question 1 to predict
styrene end-of-reaction concentrations for batch A123 with an Avg IC of
84.54 and an AvgRxTemp of 97.23.
5. Use the batch A123 stripper worksheet to:
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Insert the starting styrene concentration determined in question
4.
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Fill in formulas for the steam and redox K's using the provided formulas.
(hint: steam lbs/min is the steam lbs for the current minute minus steam
lbs for the previous minute; the redox rate is the redoxparts/min column).
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Fill in formulas for the combined K and the styrene concentration
(hint: the styrene(n-1) is the styrene concentration from the line above)
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Plot the predicted styrene concentration as a function of time; use
a logarithm scale for the styrene concentration.
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Find the reaction time required to bring the styrene concentration
below the level at which the produced latex will not exceed OSHA TWA vapor
exposure guidelines for styrene.
6. Answer these questions:
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What is meant by a latex?
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Explain what factors affect the vapor concentration of styrene above
the latex; draw a picture to portray this.
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Look up and comment on the adverse health effects for styrene