In the study to choose a catalyst (Example 3.4), another response variable (purity) was also evaluated for each of the catalyst types. A composite sample was taken from each batch produced and analyzed for purity (%). The following data were obtained:

(a) Prepare run charts for the purity data (see Example 3.4 for run order of catalyst within each shipment).

(b) Calculate the purity adjusted for feedstock shipment and prepare a run chart for the adjusted values.

(c) What are the conclusions from this study for purity?
Summarize the importance of the factor, background variable, and nuisance variables. Which catalyst would be expected to give the highest purity in future shipments? How strong is the degree of belief in this conclusion?

(d) Combine the conclusions from Example 3.4 on yield and the results on purity to develop recommendations for future catalyst use. The cost of each catalyst ($/lb) is: current, $12;
catalyst X, $10; catalyst Y, $16; and Catalyst Z, $12. What additional information is needed to develop a cost-effective recommendation for catalyst use?

Transcribed Image Text:

Purity of Sample for Each Feedstock Shipment Catalyst 1 2 3 4 5 6 99.1 99.8 99.5 98.4 99.6 99.7 Y 98.0 99.2 98.3 97.5 98.4 98.9 NO 97.0 98.3 97.9 96.8 97.7 98.3 97.9 99.1 98.6 97.2 98.5 99.0