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The origin of hydrogen generated from formaldehyde in basic solutions

Description: The isotopic composition of dihydrogen generated from formaldehyde in highly basic solutions has been investigated. It is shown that two pathways contribute to the generation of dihydrogen. In the first pathway, one hydrogen atom originates from water and the other from formaldehyde. In the second pathway both hydrogen atoms originate from the methylene moiety of the formaldehyde. For production of dihydrogen from glyoxylate only the first pathway is observed.
Date: March 1, 1996
Creator: Kapoor, S.; Barnabas, F.; Jonah, C.D.; Sauer, M.C. Jr. & Meisel, D.
Partner: UNT Libraries Government Documents Department

On the generation of H{sub 2} from formaldehyde in basic aqueous solutions

Description: The generation of H{sub 2} from formaldehyde and glyoxalate in aqueous solutions at high concentrations of hydroxide has been studied in the temperature range 21-60{degrees}C. The reaction is first order in formaldehyde and is of higher than first order in hydroxide concentration. Conversion ratio of the aldehyde to H{sub 2} increases on increasing OH{sup {minus}} concentration and on raising the temperature. It decreases on increasing aldehyde concentration due to the competition by the Cannizzaro reaction which is second order on the aldehyde. Effective rate constants and activation energies are provided.
Date: March 1, 1994
Creator: Kapoor, S.; Barnabas, F.; Jonah, C. D.; Sauer, M. C. Jr. & Meisel, D.
Partner: UNT Libraries Government Documents Department

Radiolytic and radiolytically induced generation of gases in simulated waste solutions

Description: The radiolytic generation of gases in simulated mixed waste solutions was studied. Computer modeling of the non-homogeneous kinetic processes in these highly concentrated homogeneous solutions was attempted. The predictions of the modeling simulations were verified experimentally. Two sources for the radiolytic generation of H{sub 2} are identified: direct dissociation of highly energetic water molecules and hydrogen abstraction from the organic molecules by hydrogen atoms. Computer simulation of the homogeneous kinetics of the NO{sub X} system indicate that no N{sub 2}O will be produced in the absence of organic solutes and none was experimentally detected. It was also found that long term pre-irradiation of the simulated waste solutions leads to enhanced thermal production of these two gases. 22 refs., 5 figs., 3 tabs.
Date: January 1, 1990
Creator: Meisel, D.; Sauer, M.C. Jr.; Jonah, C.D.; Diamond, H.; Matheson, M.S.; Barnabas, F. et al.
Partner: UNT Libraries Government Documents Department

Radiolytic and radiolytically induced generation of gases in simulated waste solutions

Description: The radiolytic generation of gases in simulated mixed waste solutions was studied. Computer modeling of the non-homogeneous kinetic processes in these highly concentrated homogeneous solutions was attempted. The predictions of the modeling simulations were verified experimentally. Two sources for the radiolytic generation of H{sub 2} are identified: direct dissociation of highly energetic water molecules and hydrogen abstraction from the organic molecules by hydrogen atoms. Computer simulation of the homogeneous kinetics of the NO{sub X} system indicate that no N{sub 2}O will be produced in the absence of organic solutes and none was experimentally detected. It was also found that long term pre-irradiation of the simulated waste solutions leads to enhanced thermal production of these two gases. 22 refs., 5 figs., 3 tabs.
Date: December 31, 1990
Creator: Meisel, D.; Sauer, M. C. Jr.; Jonah, C. D.; Diamond, H.; Matheson, M. S.; Barnabas, F. et al.
Partner: UNT Libraries Government Documents Department

Radiolytic Generation of Gases from Synthetic Waste, Annual Report: 1991

Description: Annual report of an Argonne National Laboratory Chemistry Division program on radiolytic generation of gases from synthetic waste. This report includes results of studies on simulated waste solutions to measure the presence and absence of organic chelators and their products.
Date: December 1991
Creator: Meisel, Dan; Diamond, H.; Horwitz, E. P.; Jonah, Charles D.; Matheson, Max S.; Sauer, M. C. et al.
Partner: UNT Libraries Government Documents Department

Radiolytic generation of gases from synthetic waste

Description: Yields of H{sub 2}, N{sub 2}O, O{sub 2}, and N{sub 2}, in simulated waste solutions, containing high nitrate, nitrite, hydroxide and aluminate, were experimentally measured in the presence and absence of moderate concentrations of organic chelators and some of their degradation products. These yields were measured at 30 and 60{degrees}C. No effect of dose rate on yield of H{sub 2} was observed and the amount of H{sub 2} increases linearly with dose and with the concentration of the organic additive. The generation of N{sub 2}O was observed only when organic solutes were present and its yield was dose rate dependent. Rate constants for H atom abstraction from the organic component by free H atoms were determined and these were correlated with the efficiency of the organic solute and in the generation of H{sub 2}. The rate of thermal generation of H{sub 2} and N{sub 2}O was also measured and was found to substantially increase in solutions that were preirradiated, presumably due to the generation of radiolytic degradation products. Computer modeling of the radiolytic precesses show the yield of H{sub 2} is strongly dependent on the nitrite concentration; the yield decreases with increasing nitrite concentration. The yield will be only weakly dependent on nitrate concentration above 0.5 M. Simulation of the homogeneous reactions that describe the chemistry of the NO{sub x} system indicate that: no N{sub 2}O will be formed in the absence of NO{sub x}-organic reactions. 18 refs., 41 figs., 13 tabs.
Date: December 1, 1991
Creator: Meisel, D.; Diamond, H.; Horwitz, E.P.; Jonah, C.D.; Matheson, M.S.; Sauer, M.C. Jr. et al.
Partner: UNT Libraries Government Documents Department

Radiolytic generation of gases from synthetic waste. Annual report, FY 1991

Description: Yields of H{sub 2}, N{sub 2}O, O{sub 2}, and N{sub 2}, in simulated waste solutions, containing high nitrate, nitrite, hydroxide and aluminate, were experimentally measured in the presence and absence of moderate concentrations of organic chelators and some of their degradation products. These yields were measured at 30 and 60{degrees}C. No effect of dose rate on yield of H{sub 2} was observed and the amount of H{sub 2} increases linearly with dose and with the concentration of the organic additive. The generation of N{sub 2}O was observed only when organic solutes were present and its yield was dose rate dependent. Rate constants for H atom abstraction from the organic component by free H atoms were determined and these were correlated with the efficiency of the organic solute and in the generation of H{sub 2}. The rate of thermal generation of H{sub 2} and N{sub 2}O was also measured and was found to substantially increase in solutions that were preirradiated, presumably due to the generation of radiolytic degradation products. Computer modeling of the radiolytic precesses show the yield of H{sub 2} is strongly dependent on the nitrite concentration; the yield decreases with increasing nitrite concentration. The yield will be only weakly dependent on nitrate concentration above 0.5 M. Simulation of the homogeneous reactions that describe the chemistry of the NO{sub x} system indicate that: no N{sub 2}O will be formed in the absence of NO{sub x}-organic reactions. 18 refs., 41 figs., 13 tabs.
Date: December 1, 1991
Creator: Meisel, D.; Diamond, H.; Horwitz, E. P.; Jonah, C. D.; Matheson, M. S.; Sauer, M. C. Jr. et al.
Partner: UNT Libraries Government Documents Department