The photocatalytic degradation of three reactive azo dyes (yellow-2, orange-16 and red-2) and one... more The photocatalytic degradation of three reactive azo dyes (yellow-2, orange-16 and red-2) and one anthraquinone reactive dye (blue-19) was studied. The reactions were carried out in a reactor with recirculation using TiO2 immobilised on glass Raschig rings (system A) and compared with a batch system using the catalyst in aqueous suspension (system B). Both reaction systems were irradiated with a 125 W, l > 254 nm lamp. The suspended TiO2 system was also studied using a 125 W 360 nm lamp (system C). Kinetic studies indicated a rapid colour removal, following the order B > A > C. The same trend was observed in COD and TOC removal profiles. The energy consumption per order of magnitude of catalytic degradation of the dyes was lower in the batch reactor (system B) than in the reactor with recirculation and immobilised TiO2 (system A).
... Finney, DJ (1978). Statistical method in biological assay p. 508. London: Charles Griffin &am... more ... Finney, DJ (1978). Statistical method in biological assay p. 508. London: Charles Griffin & Co. Ltd. Giarratano, E., Amin, O., Esteves, J., Gil, M.(1998). Heavy metals toxicity on Exosphaeroma gigas isotope, in the Beagle Chanel (Tierra del Fuego). ...
Toxicity and genotoxicity tests were performed on root cells of Allium cepa in order to evaluate ... more Toxicity and genotoxicity tests were performed on root cells of Allium cepa in order to evaluate wastewater quality following an ECF cellulose bleaching process. The results revealed a toxic effect of the effluent, with inhibition of meristem growth and generally lower values of metaphase, anaphase and telophase indices at pH 10.5 than pH 7 for all effluent concentrations. The genotoxicity effect was different from the toxic effect given that the micronucleus and the chromosomal aberration tests in anaphase-telophase cells were low over all ranges of the studied effluent concentrations.
AbstractThe combination of persulfate, zerovalent iron, and UV radiation is an advanced oxidation... more AbstractThe combination of persulfate, zerovalent iron, and UV radiation is an advanced oxidation process which allows for the degradation of high concentrations of organic dyes. This process is based on the generation of transient species with high oxidizing power, mainly the hydroxyl radical () and the sulfate radical (). The reaction was carried out in a cylindrical glass reactor using potassium peroxydisulfate as an oxidant and zerovalent iron as a catalyst. The reaction was performed in a radiation chamber using a Philips HP-120 W lamp (λ ≥ 254 nm). A Box–Behnken design and response surface methodology were employed to evaluate the effect of persulfate dosage (0.01 (−1)–0.05 (+1) g L−1), iron dosage (0.01 (−1)–0.05 (+1) g L−1), pH (2 (−1)–11 (+1)), and reaction time (10 (−1)–120 (+1) min) on the reduction of 100 mg L−1 of Kraft Lignin. Optimization of the process determined that optimal experimental conditions were acidic pH (3.5), a persulfate concentration of 0.05 g L−1, a zerovalent iron concentra...
Oil is one of the most difficult to eliminate pollutant present in the fishmeal mill wastewater i... more Oil is one of the most difficult to eliminate pollutant present in the fishmeal mill wastewater industry, due to its physical properties which allow it to expand in a fine layer on the water’s surface, inhibiting light penetration, and gaseous exchange between the water–air phases. This alters photosynthesis, which reduces dissolved oxygen content, with consequent modifications on the structure of the food chain. In order to reduce oils from wastewater, we used elementary iron in catalytic suspension with ultraviolet radiation (254 nm). The reaction was carried out in a cylindrical quartz reactor. The efficiency of the studied system was determined by means of multivariate analysis with the statistical program MODDE 7.0, where the experimental variables were pH and reaction time. The response of the treatment was given by the percentage of oil removal. The optimal experimental value obtained was 96% of oil removal, under conditions of pH = 4.8 and 40 min of reaction time. Total orga...
The photocatalytic degradation of three reactive azo dyes (yellow-2, orange-16 and red-2) and one... more The photocatalytic degradation of three reactive azo dyes (yellow-2, orange-16 and red-2) and one anthraquinone reactive dye (blue-19) was studied. The reactions were carried out in a reactor with recirculation using TiO2 immobilised on glass Raschig rings (system A) and compared with a batch system using the catalyst in aqueous suspension (system B). Both reaction systems were irradiated with a 125 W, l > 254 nm lamp. The suspended TiO2 system was also studied using a 125 W 360 nm lamp (system C). Kinetic studies indicated a rapid colour removal, following the order B > A > C. The same trend was observed in COD and TOC removal profiles. The energy consumption per order of magnitude of catalytic degradation of the dyes was lower in the batch reactor (system B) than in the reactor with recirculation and immobilised TiO2 (system A).
... Finney, DJ (1978). Statistical method in biological assay p. 508. London: Charles Griffin &am... more ... Finney, DJ (1978). Statistical method in biological assay p. 508. London: Charles Griffin & Co. Ltd. Giarratano, E., Amin, O., Esteves, J., Gil, M.(1998). Heavy metals toxicity on Exosphaeroma gigas isotope, in the Beagle Chanel (Tierra del Fuego). ...
Toxicity and genotoxicity tests were performed on root cells of Allium cepa in order to evaluate ... more Toxicity and genotoxicity tests were performed on root cells of Allium cepa in order to evaluate wastewater quality following an ECF cellulose bleaching process. The results revealed a toxic effect of the effluent, with inhibition of meristem growth and generally lower values of metaphase, anaphase and telophase indices at pH 10.5 than pH 7 for all effluent concentrations. The genotoxicity effect was different from the toxic effect given that the micronucleus and the chromosomal aberration tests in anaphase-telophase cells were low over all ranges of the studied effluent concentrations.
AbstractThe combination of persulfate, zerovalent iron, and UV radiation is an advanced oxidation... more AbstractThe combination of persulfate, zerovalent iron, and UV radiation is an advanced oxidation process which allows for the degradation of high concentrations of organic dyes. This process is based on the generation of transient species with high oxidizing power, mainly the hydroxyl radical () and the sulfate radical (). The reaction was carried out in a cylindrical glass reactor using potassium peroxydisulfate as an oxidant and zerovalent iron as a catalyst. The reaction was performed in a radiation chamber using a Philips HP-120 W lamp (λ ≥ 254 nm). A Box–Behnken design and response surface methodology were employed to evaluate the effect of persulfate dosage (0.01 (−1)–0.05 (+1) g L−1), iron dosage (0.01 (−1)–0.05 (+1) g L−1), pH (2 (−1)–11 (+1)), and reaction time (10 (−1)–120 (+1) min) on the reduction of 100 mg L−1 of Kraft Lignin. Optimization of the process determined that optimal experimental conditions were acidic pH (3.5), a persulfate concentration of 0.05 g L−1, a zerovalent iron concentra...
Oil is one of the most difficult to eliminate pollutant present in the fishmeal mill wastewater i... more Oil is one of the most difficult to eliminate pollutant present in the fishmeal mill wastewater industry, due to its physical properties which allow it to expand in a fine layer on the water’s surface, inhibiting light penetration, and gaseous exchange between the water–air phases. This alters photosynthesis, which reduces dissolved oxygen content, with consequent modifications on the structure of the food chain. In order to reduce oils from wastewater, we used elementary iron in catalytic suspension with ultraviolet radiation (254 nm). The reaction was carried out in a cylindrical quartz reactor. The efficiency of the studied system was determined by means of multivariate analysis with the statistical program MODDE 7.0, where the experimental variables were pH and reaction time. The response of the treatment was given by the percentage of oil removal. The optimal experimental value obtained was 96% of oil removal, under conditions of pH = 4.8 and 40 min of reaction time. Total orga...
Uploads
Papers by María Yeber