Electrochemical techniques were used to oxidize organic pollutants by Fenton process using a mix of H2O2 and ferrous ions at a parallel plate reactor. The first stage was to build a micro scale reactor comprising two ...Electrochemical techniques were used to oxidize organic pollutants by Fenton process using a mix of H2O2 and ferrous ions at a parallel plate reactor. The first stage was to build a micro scale reactor comprising two compartments, cathode and anode, separated by a membrane (Nafion-117). Each compartment has inlets and outlets to allow the flow of fluids (10 Lmin-1). The function of the reactor is to oxidize organic pollutants as well as to produce H2. Hydrogen is electrogenerated in the catholyte by the reduction of protons on a carbon steel cathode in acidic medium (0.05 M H2SO4). At the same time, a mixture of Fe2+/Fe3+ ions is produced in the anolyte (0.05 M Na2SO4, pH ≈ 2) by means of the oxidation of a sacrificial electrode made of stainless steel mesh. Fe2+/Fe3+ ions interact with H2O2 to generate strong oxidants which are responsible for oxidizing the organic matter and removing color. A voltage of 1 V was applied between the electrodes and remained constant, while the current observed was approximately 0.06 A. Under these conditions, the activation rate with different H2O2 concentrations (15, 20, 25, 30, 35, 40, 45 and 50 mM) was evaluated. The maximum activation rate (1.3 mM·min-1) was obtained using 30 mM H2O2. Under these conditions, the oxidation of a synthetic industrial effluent (0.615 mM BB9) was performed and the following results were obtained: 95% of this concentration was removed in 5 minutes and 15 mL of H2 was electrogenerated in 30 minutes.展开更多
Spectroscopy in the UV-Vis and NIR ranges of light provides great convenience for the characterization and evaluation of the characteristics and optical modifications that occur during life, the processes for the prep...Spectroscopy in the UV-Vis and NIR ranges of light provides great convenience for the characterization and evaluation of the characteristics and optical modifications that occur during life, the processes for the preparation of some food in order to modify their characteristics or eliminate Micro-organisms that can affect their quality and shelf life, work is carried out at elevated temperatures, even above 100°C. The study has made it possible to identify changes in the Absorbance, Transmittance and Optical Intensity of Apis mellifera honey from four different botanical sources and States of the Mexican Republic: Citrus (Citrus) from the state of Veracruz, Mangle (Rizophora mangle) of the Pacific zone of the state of Sinaloa, Polyfloralis of the state of Morelos and Polyfloralis of the state of Tabasco.展开更多
文摘Electrochemical techniques were used to oxidize organic pollutants by Fenton process using a mix of H2O2 and ferrous ions at a parallel plate reactor. The first stage was to build a micro scale reactor comprising two compartments, cathode and anode, separated by a membrane (Nafion-117). Each compartment has inlets and outlets to allow the flow of fluids (10 Lmin-1). The function of the reactor is to oxidize organic pollutants as well as to produce H2. Hydrogen is electrogenerated in the catholyte by the reduction of protons on a carbon steel cathode in acidic medium (0.05 M H2SO4). At the same time, a mixture of Fe2+/Fe3+ ions is produced in the anolyte (0.05 M Na2SO4, pH ≈ 2) by means of the oxidation of a sacrificial electrode made of stainless steel mesh. Fe2+/Fe3+ ions interact with H2O2 to generate strong oxidants which are responsible for oxidizing the organic matter and removing color. A voltage of 1 V was applied between the electrodes and remained constant, while the current observed was approximately 0.06 A. Under these conditions, the activation rate with different H2O2 concentrations (15, 20, 25, 30, 35, 40, 45 and 50 mM) was evaluated. The maximum activation rate (1.3 mM·min-1) was obtained using 30 mM H2O2. Under these conditions, the oxidation of a synthetic industrial effluent (0.615 mM BB9) was performed and the following results were obtained: 95% of this concentration was removed in 5 minutes and 15 mL of H2 was electrogenerated in 30 minutes.
文摘Spectroscopy in the UV-Vis and NIR ranges of light provides great convenience for the characterization and evaluation of the characteristics and optical modifications that occur during life, the processes for the preparation of some food in order to modify their characteristics or eliminate Micro-organisms that can affect their quality and shelf life, work is carried out at elevated temperatures, even above 100°C. The study has made it possible to identify changes in the Absorbance, Transmittance and Optical Intensity of Apis mellifera honey from four different botanical sources and States of the Mexican Republic: Citrus (Citrus) from the state of Veracruz, Mangle (Rizophora mangle) of the Pacific zone of the state of Sinaloa, Polyfloralis of the state of Morelos and Polyfloralis of the state of Tabasco.