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Introduction. Dairy industry is one of the most important sectors in industrialized and developing countries. Approximately 90% of the milk used in cheese industries is eliminated as whey (or lactoserum). Statistics indicate that lactoserum or whey is discarded as an effluent and brings a serious environmental problem, due to the fact that it affects, physically and chemically, the soil's structure. This reduces the performance of crops and, when whey is disposed by being pouring it into water bodies, aquatic life is reduced because it drains the dissolved oxygen. Objective. Evaluate a UASB reactor by means of anaerobic digestion, using two organic loads of 3 g/L/.day COD and 4 g/L/.day COD. Materials and methods. Different laboratory analyses were performed on both loads: COD, protein, sugars, VFA, methane and ammonium. Results. The results indicated that the COD efficiency was above 65%; the sugars' degradation was total and the protein degradation was higher that 78%, while the ammonium, methane and VFA concentrations were all within the normal parameters for the reactor's correct work. Conclusion. The UASB reactor is a god option to treat waste water, as it contains whey in two different organic loads. [ABSTRACT FROM AUTHOR]

Introduction. The use of pesticides in agriculture has generated important impacts: on one side, the increase of agricultural production and, on the other, a big source of environmental pollution. This fact has brought the consciousness of the importance of studying the dynamics of such pollutants in the environment and the possible alternatives to degrade them. Objective. To study the carbolysis of carbofuran in waters confluent to the crops from the East of Antioquia, by the use of a sun radiation simulator, toxicity tests and determination through liquid chromatography -with an ultra-violet detector with a diode array-.Materials and methods. To establish the best photolytic degradation conditions a 3×2×2 factorial design was used, evaluating three variables: pH (5, 7 and 9), types of water (ultra-pure and surface water) and carbofuran concentration. The response factor defined was de degradation percentage. Results. As pH increases the carbofuran's degradation percentage is more significant, with 30% and 20% of degradation at a pH of 9 during 90 minutes of irradiation in ultra-pure water and surface water, respectively. It can also be seen that under natural pH conditions -represented by water from the Ríonegro river- the removal percentages of a 10 mg L-1 and 30 mg L-1 samples, when irradiated, 9,5% and 21% of degradation are respectively obtained, which means that with low carbofuran concentrations the effect of neutral pH tends to have a lower influence on the degradation. Conclusions. The photolytic processes as primary degradation mechanisms in the environment have a significant contribution to the degradation of carbofuran when this carbofuran is at relatively high concentration rates. For the Rio Negro river waters, neither the dissolved organic matter nor a neutral pH value, had an effect on the carbofuran's degradation. Nevertheless, basic or acid pH values tend to increase the degradation of the carbofuran. [ABSTRACT FROM AUTHOR]

Introductión. Peroxidase is an enzyme known for its capability to eliminate phenolic compounds and aromatic amines in aqueous solutions. Its use has been recently proposed for discoloring textile effluents. Objective. To evaluate the effect of an artichoke extract with peroxidase activity and commercial peroxidase on the discoloration of a textile effluent and on two of the dyes within the effluent. Materials and methods. The discoloration tests were performed on a sample of the effluent that had a mixture of direct, disperse and reactive dyes from a textile company and two reactive dyes solutions. Proportions with the degrading agent 2:1 were used for all of the samples. Also, 0.1mL of hydrogen peroxide at 35% was added in order to activate the enzyme. Absorbance measurements were performed with a UV-Vis spectrophotometer. Results. The use of the artichoke extract favored the discoloration of the samples, producing a reduction in the absorbance between 40-60% from the beginning of the treatment. Conclusion. The use of artichoke extract and commercial peroxidase is a good alternative in the discoloration of textile effluents if compared to conventional methods, and artichoke extract is a promising alternative given its low cost. [ABSTRACT FROM AUTHOR]

Introduction. Environmental contamination produced by the disposal of effluents from textile industries, encourages researchers to continue their search for the removal of this dyes in waste water. Objective. To compare the effect both an artchoke extract with peroxidase activity and a conventional method, hydrogen peroxide, had in the discoloration of an effluent from a textile industry. Materials and Methods. As a sample, a mixture of direct, disperse and acid dyes was used. They were all from a textile industry located in an Antioquian municiple. The artchoke's extract and the hydrogen peroxide, and a mixture of both 1:1 were used as degradation agents. Absorbance measures were made by the use of a UV-Vis spectrophotometer. Results. For the treatment of the sample with artchoke extract, peroxide and the mixture of both, there is an absorbance reduction of 21.03%, 12.32%, 22.70%, respectively, at 486 nm and of 17.13 %, 16.43%, 28.54% at 598 nm. Conclusion. The artchoke extract provides a discoloration similar to that of the hydrogen peroxide, becoming an alternative in comparison to the use of conventional methods that bring environmental problems. [ABSTRACT FROM AUTHOR]

Introduction. Textile dyes have a great persistence in the environment and classic methods to eliminate them are useless due to the fact that oxidations or partial reductions can generate secondary products with high toxicity levels. Objective. To study the degradation and the mineralization of the Yellow Novactive F4GL dye with TiO2 and FeCl3, using the advanced oxidation processes with a ultra-violet light lamp and analyzing both the degradation and the mineralization by the use of a factorial model. Materials and methods. To make the tests a MIGHTY PURE 60 Hz ultra -violet light lamp was used, with a glass bowl which measured 41 cm × 25,5 cm × 20 cm and contained 15 L of sample. This system was complemented by a pump that had a 0,047 L/s flow. Each test was made three times, in order to reduce the experimental error. Results. The test with the highest degradation and mineralization levels was that with 60 mg/L FeCl3 and 1.0 mL/L of H2O2. It had a degradation percentage of 100 and a mineralization percentage of 70.1. Conclusion. Waste water with this dye is degraded and mineralized more rapidly with FeCl3 than with TiO2. [ABSTRACT FROM AUTHOR]

Introduction. The heterogeneous photocatalysis using titanium dioxide in suspension is an efficient technology that at the moment is applied for the degradation of recalcitrant contaminants. The use of this technique is a good alternative for the degradation of the acid-base phenolphthalein indicator, present on the liquid wastes generated by the laboratories of chemical analysis in the University of Cauca. Objective. To apply the heterogeneous photocatalysis using TiO2 suspended and H2O2, in the treatment of liquid wastes with the phenolphthalein indicator. Materials and equipment. For the photocatalysis process, a system composed of three parts was used: A photo-reactor with a lamp of ultraviolet light that has a tube of low pressure of mercury (wavelength 254 nm), a zone of homogenization and a pump for the recirculation of the sample. The conditions from which the highest percentage of degradation of the indicator was obtained, were analyzed. The specific variables analyzed in this treatment were: catalyst concentration (TiO2 Degussa P25), oxidinsing agent concentration (H2O2), and the time of exhibition to the light Uv. Results.The degradation and mineralization of the indicator in the process were evaluated by using colorimetric methods. Results. the highest percentage of degradation was 86,54% using 500 ppm of TiO2, 2600 ppm of H2O2, and 8 hours of light Uv time exposition. These standardized conditions were applied for the liquid wastes. Conclusion. the use of optimum concentrations of TiO2 and H2O2 allows to obtain good dedegradation percentages of the acid-base phenolphthalein indicator present in chemical wastes. [ABSTRACT FROM AUTHOR]