Vapor Pressures of Chlorinated Dioxins and Dibenzofurans

There are two mistakes in this paper. (a) In Table II, the column headings for furans are incorrect. The heading p,p′-. DDT should be inserted over ...
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Additions and Corrections 1988, Volume 22, 1362-1364 Brian D. Eitzer and Ronald A. Hites*: Vapor Pressures of Chlorinated Dioxins and Dibenzofurans There are two mistakes in this paper. (a) In Table II, the column headings for furans are incorrect. The heading p,p′DDT should be inserted over the column now labeled 2378, and this and all of the other headings should be shifted to the right by one column. The retention time data for 1234789 are not known. (b) The data in the fourth column of Table III, PGC (25 °C), Torr, are incorrect; the solid-phase vapor pressure for p,p′DDT was used in eq 2 instead of the subcooled liquid vapor pressure. The revised Table 3 is given here. There are also small corrections in the fitted constants C and L1/L2 in this table. As a result of these mistakes, the data originally used for the log PGC-GC retention index (RI) correlation (see Figure 1) were incorrect. These log PGC values were recalculated and regressed versus the retention indexes. The revised eq 5 from this regression (r 2 ) 0.99) is

log PGC (Torr) ) (526 - RI)/344

(5)

The values in Figure 2 for log New have been recalculated using the revised eq 5; there is still a systematic offset, but the correlation remains strong (r 2 ) 0.97). We thank Diane Wagrowski for correcting the calculations and Vladimir S. Iorish for bringing the second error to our attention.

TABLE 3. Regression Parameters and Experimental Subcooled Liquid Vapor Pressures As Determined by the Gas Chromatographic Technique (see PGC Column) for Selected Polychlorinated Dibenzo-p-dioxins and Dibenzofurans

1234 12378 123478 1234678 OCDD

L1/L2a Dioxins 0.012 0.953 -0.626 1.030 -1.222 1.090 -1.870 1.138 -2.396 1.189

2378 12378 23478 123478 and 123678 123789 and 234678 1234678

Furans 0.098 0.947 -0.458 0.988 -0.567 1.019 -1.081 1.051 -1.229 1.074 -1.658 1.099

compound

a

See eq 4.

b

Ca

PGC (25 °C), Torr

r2

4.78 × 10-6 9.38 × 10-7 2.39 × 10-7 6.73 × 10-8 2.06 × 10-8

0.99 0.90 0.98 0.99 0.96

5.63 × 10-6 1.90 × 10-6 1.15 × 10-6 4.54 × 10-7 2.91 × 10-7 1.38 × 10-7

0.99 0.95b 0.88 0.98 0.98 0.99

Point at 150 °C removed.

ES982009V

2804

9

ENVIRONMENTAL SCIENCE & TECHNOLOGY / VOL. 32, NO. 18, 1998

S0013-936X(98)02009-4 CCC: $15.00

 1998 American Chemical Society Published on Web 08/15/1998