Dissolution rate, Fredonia

Low pH increased the dissolution rates of both CaCOs and MgCC>3 for all the stones as expected. Figure 2 graphically illustrates the effect of pH on the CaCC>3 dissolution rate. Fredonia shows the greatest increase in dissolution at the lower pH. However, both Brassfield and Pfizer also show substantial increases in dissolution rate. 

Comparing the CaCC>3 dissolution rates for the three stones, Fredonia appears to dissolve only slightly faster than either Pfizer or Brassfield with Brassfield the slowest of the three. 

The differences in the MgCOs dissolution rates are more significant again, Fredonia appears to be the fastest dissolving. 

Figure 3. Dissolution rate at pH 5.8 vs. reciprocal temperature—Fredonia limestone.

Figure 4. Fredonia limestone dissolution rate vs. stirring rate, (50°C pH 5.8).

Stirring rate appeared to have little effect on the CaC03 and MgC03 dissolution rates for the Fredonia limestone at pH 5.8. 

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