2.2.2.2 RELATIONSHIP BETWEEN BTA
CONCENTRATION AND ECT
Figure 8 shows the trends of ECT and the concentration of
BTA of oil containing octyl sulfoxide with 100 g of
pressboard (No. 12 and 14 in Table 2). The concentration of
BTA decreases while the ECT increases during the test.
Figure 9 shows the concentrations of BTA and dissolved
copper. The concentration of dissolved copper increases as the
decrease of BTA concentration. The concentration of
dissolved copper in the oil with the addition of 10 ppm of
BTA is higher than that of 34 ppm. Figure 10 shows the
correlation between the concentration of BTA and ECT. The
increase in ECT occurs when the concentration of BTA is less
than 10 ppm. Figure 11 shows the correlation between the
concentrations of BTA and dissolved copper. The
concentration of dissolved copper increases significantly when
the concentration of BTA is less than 10 ppm.