Application of Ionizing Radiation to Environment Protection

Abstract

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Energy Efficient Removal of Volatile Organic Compounds (VOCs) and Organic Hazardous Air Pollutants (o-HAPs) from Industrial Waste Streams by Direct Electron Oxidation

“…The diagram of the test system is shown in Figure 3 and results are shown in Figure 4. The data were DE-EE0003494 consistent with prior published work [2][3][4][5][6][7][8] and confirmed that it is important to characterize the electron beam oxidation for the family of compounds that will be used in the final application if absolute destruction efficiencies are to be determined. Note that, within a compound family, relative destruction efficiency (i.e., ease of oxidation) increases with increasing molecular complexity.…”

“…Typical dose requirements for VOC/o-HAP oxidation by electrons are 5 to 15kGy. [4][5][6][7] For a fixed energy, increased dose is applied by increasing the electron current that is drawn from the filament and delivered through the emitter window.…”

Application of Ionizing Radiation in Wastewater Treatment: An Overview

“…It should be noted that in some cases, it is very hard to determine if the reaction is electron transfer or radical addition/elimination. Successive reduction of Cr species from (VI) state to (III) state is achieved via reaction with H [32]. On the other hand, cadmium (II) and lead (II) are reduced via reaction with H or/and e − aq (Equation (10)) to produce Cd(I) that undergoes disprotonation (Equation (11)) or oxidization through a reaction with OH − or H2O2 (Equation (12)), or react with hydrogen to produce unstable MH + species that decay (Equation (13)) [18].…”

“…To reduce the oxidation effect and subsequently to enhance cadmium and lead precipitation, an organic OH − scavenger could be used or the process could be operated in the absence of oxygen [31][32][33]. Ionizing radiation can reduce various forms of mercury via reaction with e − aq (Equation (5)) and H (Equation (6)) to form unstable compound that dimerized (Equation (7)) to produce insoluble form [31,32].…”

“…To reduce the oxidation effect and subsequently to enhance cadmium and lead precipitation, an organic OH − scavenger could be used or the process could be operated in the absence of oxygen [31][32][33].…”