In an emulsion liquid membrane system, an emulsion (internal phase) is dispersed into an external liquid medium containing a contaminant. The contaminant is removed from the external liquid through mass transfer into the emulsion. Internal phase leakage occurs when portions of the extracted

Question

In an emulsion liquid membrane system, an emulsion (internal phase) is dispersed
into an external liquid medium containing a contaminant. The contaminant is removed
from the external liquid through mass transfer into the emulsion. Internal phase leakage
occurs when portions of the extracted material spill into the external liquid. In the article
"Leakage and Swell in Emulsion Liquid Membrane Systems: Batch Experiments"
(R. Pfeiffer, W. Navidi, and A. Bunge, Separation Science and Technology, 2003:
5 19-539), the effects of five factors were studied to determine the effect on leakage in a
certain system. The five factors were A: surfactant concentration, B: internal phase lithium hydroxide concentration, C: membrane phase, D: internal phase volume fraction, and E: extraction vessel stirring rate. A half-fraction of a 2[latex]^5[/latex] design was used. The data are presented in the following table (in the actual experiment, each point actually represented the average of two measurements). Leakage is measured in units of percent. Assume that the third-, fourth-, and fifth-order interactions are negligible. Estimate the main effects and two-way interactions. Which, if any, stand out as being noticeably larger than the rest?

Accepted Answer

Using the sign table (Table 9.1 2), we compute estimates for the main effects and two-way interactions, shown in the following table.

[latex]\begin{array}{lr||lr}\hline ext{Term}& ext{Effect}& ext{Term}& ext{Effect}\\hline A & -2.36 & A E & -1.15 \B & 3.00 & B C & 0.20 \C & -0.11 & B D & 0.86 \D & 1.68 & B E & 2.65 \E & 2.64 & C D & -1.30 \A B & -1.54 & C E & 0.61 \A C & 1.43 & D E & 1.32 \A D & 0.17 & & \\hline\end{array}[/latex]

Note that we do not bother to compute sums of squares for the estimates, because we have no SSE to compare them to. To determine informally which effects may be most worthy of further investigation, we rank the estimates in order of their absolute values: B: 3.00, BE: 2.65, E: 2.64, A: -2.36, D: 1.68, and so forth. It seems reasonable to decide that there is a fairly wide gap between the A and D effects, and therefore that factors A, B, and E are most likely to be important.

Treatment Leakage		Treatment Leakage		Treatment Leakage		Treatment Leakage
e	0.61	c	0.35	d	2.03	cde	1.45
a	0.13	ace	0.075	ade	0.64	acd	0.31
b	2.23	bce	7.31	bde	11.72	bcd	1.33
abe	0.095	abc	0.080	abd	0.56	abcde	6.24

Question 9.17: In an emulsion liquid membrane system, an emulsion (internal...

Related Answered Questions

A 2^5 factorial experiment was conducted to estimate the effects of five factors on the quality of lightbulbs manufactured by a certain process. The factors were A: plant (1 or 2), B: machine type (low or high speed), C: shift (day or evening), D: lead wire material (standard or new), and E: ...

Verified Answer:

The following output (from MTNITAB) presents the ANOVA table for the weld data in Table 9.1 (in Section 9.1). Which pairs of fluxes, if any, can be concluded, at the 5% level, to differ in their effect on hardness? ...

Verified Answer:

For the data in Table 9.1, compute MSTr, MSE, and F . Find the P-value for testing the null hypothesis that all the means are equal. What do you conclude? ...

Verified Answer:

Refer to Example 9.14. Construct an ANOVA table. For each effect and interaction, test the null hypothesis that it is equal to 0. Which factors, if any, seem most likely to have an effect on the outcome? ...

Verified Answer:

The design suggested in Example 9. 12 has been adopted, and the experiment has been carried out. The results (from MTNITAB) follow. Does the output indicate any violation of necessary assumptions? What do you conclude regarding the effect of drill speed on excess diameter? ...

Verified Answer:

Verified Answer:

Verified Answer:

The article “Uncertainty in Measurements of Dennal Absorption of Pesticides” (W . Navidi and A. Bunge, Risk Analysis, 2002:11 75-1182) describes an experiment in which a pesticide was applied to skin at various concentrations and for various lengths of time. The outcome is the amount of the ...

Verified Answer:

Use the preceding ANOVA table to determine whether the additive model is plausible for the yield data. If the additive model is plausible, can we conclude that either the catalyst or the reagent affects the yield? ...

Verified Answer:

In Example 9.4 (in Section 9.1), several measurements of the maximum hourly concentrations (in μg/m³) of SO2 were presented for each of four power plants, and it was concluded that the mean concentrations at the four plants were not all the same. The following output (from MINITAB) ...

Verified Answer: