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H2S--Can it be dissociated via Microwaves
- Thread starter bonzoboy
- Start date
1) I doubt that microwaving would be efficient at breaking down H[sub]2[/sub]S. Note that a microwave oven excites H[sub]2[/sub]O molecules of the same structure but doesn't come close to breaking them.
2) If one did break apart an H[sub]2[/sub]S molecule (maybe using a laser), you'd have 2 H[sup].[/sup] and one S[sup]..[/sup] radical in close proximity. Maybe reform H[sub]2[/sub]S!
3) Maybe useful to consider the thermal stability of H[sub]2[/sub]S on the above. Above the melting point of sulfur, have
[Δ]G[sub]f[sub]H[sub]2[/sub]S[/sub][/sub] = -86920.2 + 7.26474*T*log(T) + 23.95049*T J/mol [T = 800-1200 K]
derived from JANAF data.
2) If one did break apart an H[sub]2[/sub]S molecule (maybe using a laser), you'd have 2 H[sup].[/sup] and one S[sup]..[/sup] radical in close proximity. Maybe reform H[sub]2[/sub]S!
3) Maybe useful to consider the thermal stability of H[sub]2[/sub]S on the above. Above the melting point of sulfur, have
[Δ]G[sub]f[sub]H[sub]2[/sub]S[/sub][/sub] = -86920.2 + 7.26474*T*log(T) + 23.95049*T J/mol [T = 800-1200 K]
derived from JANAF data.
Bonzoboy
Kenvlach's response reminds me that one of the problems with handling H2S in the first place (in pipelines) is its propensity to dissociate and drop out solid sulfur. At the same time it gives off H+ which can migrate through the lattice of the containment vessel material giving rise to the need for highZ plate and HIC testing.
If you are trying to separate sulfur from hydrogen in large amounts, be prepared for metallurgical issues.
Otherwise, I'd go with Kenvlach's heat of formation solution. In a given containment volume you can calculate the input energy requirements to raise the H2S to instability which will give you the cooking time. H2S is an unsymmetrical molecule so it should be excitable.
You would need some fancy design for the containment vessel. Where would you put the magnetron?
Laser might be a more easily controlled tool.
Stand very clear the first time you try it.
Wild scheme.. fill a ballon with H2S, Cook it to dissociate the gas and finish up with hydrogen on the outside and sulfur on the inside ... WOW!! I'm a genius.
Or did someone already invent the molecular seive?![[ponder]](/data/assets/smilies/ponder.gif "[ponder] [ponder]")
Kenvlach's response reminds me that one of the problems with handling H2S in the first place (in pipelines) is its propensity to dissociate and drop out solid sulfur. At the same time it gives off H+ which can migrate through the lattice of the containment vessel material giving rise to the need for highZ plate and HIC testing.
If you are trying to separate sulfur from hydrogen in large amounts, be prepared for metallurgical issues.
Otherwise, I'd go with Kenvlach's heat of formation solution. In a given containment volume you can calculate the input energy requirements to raise the H2S to instability which will give you the cooking time. H2S is an unsymmetrical molecule so it should be excitable.
You would need some fancy design for the containment vessel. Where would you put the magnetron?
Laser might be a more easily controlled tool.
Stand very clear the first time you try it.
Wild scheme.. fill a ballon with H2S, Cook it to dissociate the gas and finish up with hydrogen on the outside and sulfur on the inside ... WOW!! I'm a genius.
Or did someone already invent the molecular seive?
- Thread starter
- #5
Bonzoboy
Full thermal dissociation is around 650 degC I think.
I suspct that the low pressure dissociation is promoted by low partial pressure. I never looked at the energy structure in any detail but there has to be someone out there who did.
There has been research doing this with electrical potentials.
If you are rally serious about this I suggest going to your local technical library and do some searches on
David
Full thermal dissociation is around 650 degC I think.
I suspct that the low pressure dissociation is promoted by low partial pressure. I never looked at the energy structure in any detail but there has to be someone out there who did.
There has been research doing this with electrical potentials.
If you are rally serious about this I suggest going to your local technical library and do some searches on
David
Hydrogen sulfide breakdown is aided by a catalyst surface & the presence of oxygen to form water and sometimes SO[sub]2[/sub]. The standard enthalpy of combustion of H[sub]2[/sub]S is -518 kJ/mole. Forget about a purely thermal decompsition unless you have a metal to act as a sulfur 'sink' by forming sulfide; H[sub]2[/sub]S-H[sub]2[/sub] gas mixtures are used to study metal-metal sulfide equilibria over a wide range of temperatures.
Some very interesting papers:
'Electrochemical Membrane Separation (EMS) of Hydrogen Sulfide from Coal Gasification Streams.'
'Hydrogen Production from Hydrocarbons, H2O and H2S,. Stimulated by Non-Thermal Atmospheric Pressure Plasma
'High-Temperature Pyrolysis by Laser Gas Breakdown' Ind. Eng. Chem. Prod. Res. Dev., vol. 20, 396-399 (1981)
[abstract only]
'Production of Hydrogen and Sulfur from Hydrogen Sulfide in a Nonthermal-Plasma Pulsed Corona Discharge Reactor'
-- abstract only, from a 2005 conference:
Some very interesting papers:
'Electrochemical Membrane Separation (EMS) of Hydrogen Sulfide from Coal Gasification Streams.'
'Hydrogen Production from Hydrocarbons, H2O and H2S,. Stimulated by Non-Thermal Atmospheric Pressure Plasma
'High-Temperature Pyrolysis by Laser Gas Breakdown' Ind. Eng. Chem. Prod. Res. Dev., vol. 20, 396-399 (1981)
[abstract only]
'Production of Hydrogen and Sulfur from Hydrogen Sulfide in a Nonthermal-Plasma Pulsed Corona Discharge Reactor'
-- abstract only, from a 2005 conference:
In the publication "Sulphur" March 1993 there is an article that talks about the use of microwaves for recovery of sulphur from waste gas containing H2S. This research used a microwave discharge to generate "cold" non-equilibrium plasma that dissociates hydrogen sulphide into hydrogen and sulphur. The research was being done in the US and Russia.
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