Catalyst K ([min.sup.-1]) [t.sub.1/2] (min) M1 500[degrees]C 0.0121 57.38 M2 500[degrees]C 0.0200 34.57 M3 500[degrees]C 0.0123 56.49 M4 500[degrees]C 0.0127 67.96 M5 500[degrees]C 0.0146 47.57 M6 500[degrees]C 0.0164 42.21 M7 500[degrees]C 0.0118 58.69 Catalyst Photodegradation (%) M1 500[degrees]C 84.0 M2 500[degrees]C 100.0 M3 500[degrees]C 98.8 M4 500[degrees]C 85.5 M5 500[degrees]C 98.0 M6 500[degrees]C 98.7 M7 500[degrees]C 97.8 Table 6: Comparison of different photocatalysts used in 2,4,6- trichlorophenol photodegradation.
There are five basic types of chlorophenols: monochlorophenols, dichlorophenols, trichlorophenols, tetrachlorophenols, and pentachlorophenols.
Upon mixing the difficult-to-destroy trichlorophenols
with hydrogen peroxide, then adding the iron-containing catalyst, the chemists found that the chlorine atoms freed by TCP breakup linked with other molecules to form four relatively benign products.
Caption: Figure 5: UV-vis spectra of photocatalytic degradation of 2,4,6- trichlorophenol
by mixed oxide catalysts at 500[degrees]C and Degussa p25 Ti[O.sub.2].
On 10 July 1976, an explosion at a trichlorophenol
manufacturing plant near Seveso, Italy, resulted in the highest TCDD levels known in human residential populations (Mocarelli et al.
In July 1976, a trichlorophenol
plant explosion near Seveso, Italy, resulted in dioxin contamination of the surrounding area.
In this study, we assessed the association between human dioxin exposure in utero and during breast-feeding and adverse human adult male reproductive outcomes, as measured in men whose mothers were exposed to dioxin as a result of the trichlorophenol
plant explosion near Seveso, Italy, in July 1976 (Mocarelli et al.
Young rationalizes in this book that the omission of maximum dioxin contaminant levels from the military specifications for herbicide quality occurred because not enough was known and measurement was difficult; but two decades ago his edited volume stated that "the manufacturers of trichlorophenol
and of 2,4,5-T had been aware for many years that this class of compounds and particularly their impurities produced a toxic reaction in humans ...
It was noted that simple phenols and in particular trichlorophenols
, trijodophenols and butylphenol may block ion channels in a micromolar concentrations range.
Pichat, "Photodegradation of dichlorophenols and trichlorophenols
in Ti[O.sub.2] aqueous suspensions: kinetic effects of the positions of the Cl atoms and identification of the intermediates," Journal of Photochemistry and Photobiology A: Chemistry, vol.