The discrepancies between polychlorinated dibenzo-p-dioxin to polychlorinated dibenzofuran (PCDD to PCDF) ratios in laboratory and field studies in the exhaust of combustion sources are not fully explained by available formation models. In this paper we present the results of experimental studies of the surface mediated formation of PCDD/F at the conditions mimicking the combustion cool zone fr...

In order to clarify urinary metabolites of p-chloroaniline (p-CA), urine samples of a patient acutely poisoned with p-CA were analyzed by gas chromatography/mass spectrometry. Urinary metabolites were extracted with diethylether at pH 1.0 and pH 10 from urine samples hydrolyzed with acid and base and from intact urine samples. Aliquots of the ethereal extracts were injected into the gas chromat...

The crystal structure of the 3-chlorocatechol 1,2-dioxygenase from the Gram-positive bacterium Rhodococcus opacus (erythropolis) 1CP, a Fe(III) ion-containing enzyme specialized in the aerobic biodegradation of 3-chloro- and methyl-substituted catechols, has been solved by molecular replacement techniques using the coordinates of 4-chlorocatechol 1,2-dioxygenase from the same organism (PDB code...

1. A pseudomonad capable of utilizing 4-chlorophenoxyacetate (CPA) as sole source of organic carbon was isolated from soil. 2. The organism was grown in liquid culture and the following compounds were isolated and identified in culture extracts: 4-chloro-2-hydroxyphenoxyacetate, 4-chlorocatechol, beta-chloromuconate probably the cis-trans isomer and gamma-carboxymethylene-Delta(alphabeta)-buten...

background: chlorophenols are classified as priority toxic pollutants. these acidic organic compounds present a serious potential hazard for human health and aquatic life. chlorophenols accumulate in water, soil and air due to high stability, and impart an unpleasant taste and odor to drinking water and can exert negative effects on different biological processes. among the different methods of...

A new activated carbon was produced from pulp and paper mill sludge as a low cost precursor via chemical activation by zinc chloride. The activated carbon was successfully used for the adsorption of phenol and two of its derivatives, i.e. 2-chlorophenol and 4-nitrophenol from aqueous solutions. The characterization of the prepared activated carbon demonstrated high textural properties for the s...

In this study, activated carbon synthesized from Aloe vera green wastes was used as a sorbent to remove 4-chlorophenol (4-CP) from aqueous solutions. The influence of contact time (0-100 minutes), pH (2-8), adsorbent dosage (1-9 g/l), and initial 4-CP concentration (10-60 mg/l) in batch system was investigated on the sorption. The sorbent was specified using scanning electron microscopy (SEM). ...