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Figure 1. shows effluent pH over time. The green line represents the 2.5cm diameter tube settler, and the 5cm diameter tube settler is represented by yellow and orange lines. We can see that none of the runs were anywhere close to reaching the goal of twelve hours with a saturated effluent. Both tap water and distilled water runs with the 5cm diameter tube settler failed within an hour and a half, while the run with the 2.5 cm diameter tube settler never produced any saturated effluent. There is certainly no performance improvement running the reactor with distilled water.
Figure 1. Effluent pH vs time in hours. Comparison of performance between tap water and distilled water.
Figure 2. shows the fraction of saturated hydroxide concentration versus the fraction of time the run is theoretically calculated to last. This is simply a clearer way to display the reactor's performance over the course of the experiment relative to our goal, which would be to have a straight line at an OH fraction of one. In this case, Figure 2. illustrates what are likely measurement errors: a hydroxide concentration nearly double the saturation value in one run and a failure to reach saturation in what should be an identical trial.
Figure 2. Fraction of saturated hydroxide vs Fraction of time
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