Organic compounds in sludges 229
fires involving electrical transformers and capacitors have demonstrated the potential for formation of hazardous levels of polychlorodibenzofurans from pyrolysis of
polychlorobiphenyls [121–124].
Pentachlorophenol, a large-volume fungicide and wood preservative, contains
relatively high levels of hexa-, hepta- and octachlordibenzo-dioxins and essentially no tetrachlorodibenzo-p-dioxins [103–105]; and polychlorodibenzo-p-dioxin
incineration of materials containing chlorophenols readily produces mixtures of
polychlorodibenzo-p-dioxins, but 2,3,7,8-tetrachlorodibenzo-p-dioxin is a minor
component. On the other hand, the highly toxic 1,2,3,7,8-pentachloro isomer is a
major component of polychlorodibenzo-p-dioxins and polychlorodibenzofurans usually produce mixtures of distinctly different relative component abundances [103].
On the other hand, the preferential accumulation of certain isomers in animals may
prevent source identification from analyses of biological samples.
Hagenmaier et al [125] found polyhologenated dioxins, furans and diphenyl ethers
in industrial waste water sludge.
10.4 NITROGEN CONTAINING COMPOUNDS
10.4.1 Nitrilo acetic acid
Potentiometric titration
Sekerka et al [126] described a thallium nitrite potentiometric titration procedure for
the determination of down to 0.1 µg l
−1 of nitriloacetic acid in waste water and sewage.
To the sample was added 0.0 M thallium nitrite and 10 M sodium hydroxide, the mixture was filtered, the filtrate adjusted to pH7 by addition of nitric acid and hexamine
and 0.01 M ammonium pyrrolidine-1-carbodithioate added (this preliminary treatment removes interfering cations and reducing substances). The solution was titrated
with 0.1 M thallium nitrite (T1
3+ forms a 1:2 complex with nitriloacetate and 1 : 1
complexes with EDTA) with the use of a combination platinum redox electrode (Orion
96–78). A second portion of sample is treated similarly, but in the first step 0.01 M
cupric nitrite is added in place of the thallium nitrite and titrated with 0.1 mM cupric
nitrite (Cu
2+ forms 1:1 complexes with all the complexing agents tested). The titration
curves exhibit two end points corresponding to:
1 T1
3+ or (Cu
2+ ) consumed by ammonium pyrrolidine-1-carbodithioate and
2 Nitriloacetic acid (or other ligands) present in the sample.
The content of nitriloacetic acid is calculated from the differences in titres. The
recovery of nitriloacetic acid in admixture with EDTA in synthetic sewage samples
range from 90 to 102%
Gas chromatography
Warren and Malec et al [127] determined nitriloacetic acid and related aminopolycarboxylic acids (iminodiacetic acid, glycine, and sarcosine) in sewage by converting
to the butyl or the N-trifluoracetyl esters followed by chromatography in dual
glass U shaped columns packed with 0.65% of ethanediol adipate on acid washed
fires involving electrical transformers and capacitors have demonstrated the potential for formation of hazardous levels of polychlorodibenzofurans from pyrolysis of
polychlorobiphenyls [121–124].
Pentachlorophenol, a large-volume fungicide and wood preservative, contains
relatively high levels of hexa-, hepta- and octachlordibenzo-dioxins and essentially no tetrachlorodibenzo-p-dioxins [103–105]; and polychlorodibenzo-p-dioxin
incineration of materials containing chlorophenols readily produces mixtures of
polychlorodibenzo-p-dioxins, but 2,3,7,8-tetrachlorodibenzo-p-dioxin is a minor
component. On the other hand, the highly toxic 1,2,3,7,8-pentachloro isomer is a
major component of polychlorodibenzo-p-dioxins and polychlorodibenzofurans usually produce mixtures of distinctly different relative component abundances [103].
On the other hand, the preferential accumulation of certain isomers in animals may
prevent source identification from analyses of biological samples.
Hagenmaier et al [125] found polyhologenated dioxins, furans and diphenyl ethers
in industrial waste water sludge.
10.4 NITROGEN CONTAINING COMPOUNDS
10.4.1 Nitrilo acetic acid
Potentiometric titration
Sekerka et al [126] described a thallium nitrite potentiometric titration procedure for
the determination of down to 0.1 µg l
−1 of nitriloacetic acid in waste water and sewage.
To the sample was added 0.0 M thallium nitrite and 10 M sodium hydroxide, the mixture was filtered, the filtrate adjusted to pH7 by addition of nitric acid and hexamine
and 0.01 M ammonium pyrrolidine-1-carbodithioate added (this preliminary treatment removes interfering cations and reducing substances). The solution was titrated
with 0.1 M thallium nitrite (T1
3+ forms a 1:2 complex with nitriloacetate and 1 : 1
complexes with EDTA) with the use of a combination platinum redox electrode (Orion
96–78). A second portion of sample is treated similarly, but in the first step 0.01 M
cupric nitrite is added in place of the thallium nitrite and titrated with 0.1 mM cupric
nitrite (Cu
2+ forms 1:1 complexes with all the complexing agents tested). The titration
curves exhibit two end points corresponding to:
1 T1
3+ or (Cu
2+ ) consumed by ammonium pyrrolidine-1-carbodithioate and
2 Nitriloacetic acid (or other ligands) present in the sample.
The content of nitriloacetic acid is calculated from the differences in titres. The
recovery of nitriloacetic acid in admixture with EDTA in synthetic sewage samples
range from 90 to 102%
Gas chromatography
Warren and Malec et al [127] determined nitriloacetic acid and related aminopolycarboxylic acids (iminodiacetic acid, glycine, and sarcosine) in sewage by converting
to the butyl or the N-trifluoracetyl esters followed by chromatography in dual
glass U shaped columns packed with 0.65% of ethanediol adipate on acid washed