In order to investigate the effects of import electric power by
negative corona, we performed measurements of CO2 conversions
and selectivity of products with power. We found that, as shown in
Fig. 4, the CO2 conversion appear to increase with the input power,
probably because with increase of discharged electrons per second
or discharge current, there will be more electrons to attach to CO2
and H2O, leading to more energy transfer and high conversion of
CO2. Moreover, since chemical reaction rates could depend on
the concentrations of negative ions which only could be created
by attachment of electron on CO2 and H2O steam, more electric
current could induce more electron attachment and drive the
CO2 conversion forward to form ethanol and methanol. As shown
in Fig. 4, it appears that the selectivity of CH3OH and CH3CH2OH
keep increasing with increase of input electricity, indicating that
by this process, electric energy is transferred to chemical energy,
producing more fuel with more input energy.
We infer that the possible mechanisms are as follows:
CO2 þ e ! CO þ
1
2 O2 ð2Þ
CO2 þ e ! CO
2 ð3Þ
Under low-energy negative corona discharge, water vapor could
form anions. The possible mechanisms are as follows:
H2O þ e ! H2O ð4Þ
We speculate that, once the anions or negative ion plasma are
formed under electron discharge, the following process may occur:
3H2O þ 2CO2 ! C2H5OH þ 3O2 þ 3e ð5Þ
3H2O þ 2CO ! C2H5OH þ 2O2 þ 3e ð6Þ
C2H5OH þ H2O ! 4H
2 þ 2CO ð7Þ
2H
2 þ CO ! CH3OH þ 2e ð8Þ
In such a unipolar or negatively corona discharge, water vapor
and carbon dioxide may form stable negative ions as reducing
agents to form ethanol and methanol. It is our belief that as long
as the total energy of anions obtained from the negative corona
discharge by electron attachment is larger than the Gibbs free
energy differences for the given gaseous reactions, the reduction
process could inevitably be driven forward to products with significant
conversion. It is known [7] that the work needed to remove
electrons from the corona electrode surface is approximately 4–
5 eV for the metals most likely to be used in corona discharge
devices. Since each of reactions (4) and (5) need three moles of
H2O anions or discharged electrons to drive the reactions, 5 eV
energy for each mole of discharged electron or 482.5 kJ/mol is
transferred to system. Once three moles of anions by negative discharge
could form, they may obtain the energy of 1477.5 kJ, which
is beyond the change of the standard Gibbs free energy (1306.1 kJ)
at the standard conditions for reactions (4)–(6), so that those processes
could become fully feasible.
Methanol as
In order to investigate the effects of import electric power bynegative corona, we performed measurements of CO2 conversionsand selectivity of products with power. We found that, as shown inFig. 4, the CO2 conversion appear to increase with the input power,probably because with increase of discharged electrons per secondor discharge current, there will be more electrons to attach to CO2and H2O, leading to more energy transfer and high conversion ofCO2. Moreover, since chemical reaction rates could depend onthe concentrations of negative ions which only could be createdby attachment of electron on CO2 and H2O steam, more electriccurrent could induce more electron attachment and drive theCO2 conversion forward to form ethanol and methanol. As shownin Fig. 4, it appears that the selectivity of CH3OH and CH3CH2OHkeep increasing with increase of input electricity, indicating thatby this process, electric energy is transferred to chemical energy,producing more fuel with more input energy.We infer that the possible mechanisms are as follows:CO2 þ e ! CO þ12 O2 ð2ÞCO2 þ e ! CO2 ð3ÞUnder low-energy negative corona discharge, water vapor couldform anions. The possible mechanisms are as follows:H2O þ e ! H2O ð4ÞWe speculate that, once the anions or negative ion plasma areformed under electron discharge, the following process may occur:3H2O þ 2CO2 ! C2H5OH þ 3O2 þ 3e ð5Þ3H2O þ 2CO ! C2H5OH þ 2O2 þ 3e ð6ÞC2H5OH þ H2O ! 4H
2 þ 2CO ð7Þ
2H
2 þ CO ! CH3OH þ 2e ð8Þ
In such a unipolar or negatively corona discharge, water vapor
and carbon dioxide may form stable negative ions as reducing
agents to form ethanol and methanol. It is our belief that as long
as the total energy of anions obtained from the negative corona
discharge by electron attachment is larger than the Gibbs free
energy differences for the given gaseous reactions, the reduction
process could inevitably be driven forward to products with significant
conversion. It is known [7] that the work needed to remove
electrons from the corona electrode surface is approximately 4–
5 eV for the metals most likely to be used in corona discharge
devices. Since each of reactions (4) and (5) need three moles of
H2O anions or discharged electrons to drive the reactions, 5 eV
energy for each mole of discharged electron or 482.5 kJ/mol is
transferred to system. Once three moles of anions by negative discharge
could form, they may obtain the energy of 1477.5 kJ, which
is beyond the change of the standard Gibbs free energy (1306.1 kJ)
at the standard conditions for reactions (4)–(6), so that those processes
could become fully feasible.
Methanol as
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