Condition of disharge sulfat anions on anode
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Condition of disharge sulfat anions on anode
If sulfat anions discharge on anode in sulfuric acid
producing persulfuric anions (S2O8)2-. But if this happens in melted sulfate producing SO3 and O or SO2 and O2. Why? What conditions effect on this processes? 100% sulfuric acid is not conducting current but if in 100% acid soluble the sulfate (example Al2(SO4)3) then this liquid will conduct current. And what we get in anode space in this liquid? (S2O8)2- or SO3 + O?
producing persulfuric anions (S2O8)2-. But if this happens in melted sulfate producing SO3 and O or SO2 and O2. Why? What conditions effect on this processes? 100% sulfuric acid is not conducting current but if in 100% acid soluble the sulfate (example Al2(SO4)3) then this liquid will conduct current. And what we get in anode space in this liquid? (S2O8)2- or SO3 + O?
Re: Condition of disharge sulfat anions on anode
Af anybody know books about this thematic please give a links.
- ChenBeier
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Re: Condition of disharge sulfat anions on anode
No
In diluted sulfuric acid or solution of sulfate salts, SO4 2- will be not discharged, instead of Oxygen will be developed.
2 H2O + 2 SO4 2- => 2 H2SO4 + O2 + 4e-
In molten alkalisulfates peroxodisulfate will be created. Technical method to produce persulfates
2 SO4 2- => S2O8 + 2 e-
https://en.m.wikipedia.org/wiki/Sodium_persulfate
If heavy metal sulfates are used they get decomposed to sulfuroxide, oxygen and remaning oxides.
In diluted sulfuric acid or solution of sulfate salts, SO4 2- will be not discharged, instead of Oxygen will be developed.
2 H2O + 2 SO4 2- => 2 H2SO4 + O2 + 4e-
In molten alkalisulfates peroxodisulfate will be created. Technical method to produce persulfates
2 SO4 2- => S2O8 + 2 e-
https://en.m.wikipedia.org/wiki/Sodium_persulfate
If heavy metal sulfates are used they get decomposed to sulfuroxide, oxygen and remaning oxides.
Re: Condition of disharge sulfat anions on anode
Heavy metal like a iron?
Re: Condition of disharge sulfat anions on anode
100% H2S04 have no water and electrolytic creating the oxygen by discharge OH- anions is impossible this liquid have no OH- anions and have no H2O. It's a pure sulfuric acid.
- ChenBeier
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Re: Condition of disharge sulfat anions on anode
Sulfate of Sulfuric acid will convert to peroxodisulfate, further to disulfate and sulfurtrioxide.
2 SO4 2-=> S2O8 2- + 2 e-
2 S2O8 2- => 2 S2O7 2- + O2
S2O7 2- => SO4 2- + SO3
2 SO4 2-=> S2O8 2- + 2 e-
2 S2O8 2- => 2 S2O7 2- + O2
S2O7 2- => SO4 2- + SO3
Re: Condition of disharge sulfat anions on anode
If i make electrolysis melted NaHSO4 what i get Na2S2O8 or SO3 + O?
Re: Condition of disharge sulfat anions on anode
But where this happened? In liqud sulfuric acid or in melted sulfate? Why peroxidsulfate not created in melted sulfates because high temperature? Peroxidsulfat anions will destroing by temperature or what?
- ChenBeier
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Re: Condition of disharge sulfat anions on anode
Water free sulfuric acid is like a melted sulfate. Alkalisulfates will stop at Peroxodisulfate, iron, chromium and others decompose to sulfuroxides.
Re: Condition of disharge sulfat anions on anode
But water free sulfuric acid not conducting current (because H2SO4 molecule is associated). But if i soluble sulfate in water free sulfuric acid i get current conducting liquid. The question what i get on anode when will do electrolisis in this liquid?
- ChenBeier
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Re: Condition of disharge sulfat anions on anode
Conc. sulfuric acid has an conductivity of 1,044 · 10−2 S/cm.
It has an autoprotolysis like water
2 H2SO4 => H3SO4+ + HSO4-
A sulfate salt enhance because more HSO4- is produced
H2SO4 + Na2SO4 => 2 NaHSO4
It has an autoprotolysis like water
2 H2SO4 => H3SO4+ + HSO4-
A sulfate salt enhance because more HSO4- is produced
H2SO4 + Na2SO4 => 2 NaHSO4
Re: Condition of disharge sulfat anions on anode
Ok! But how about anode processes in this liquid ( H2SO4 + Na2SO4 without water)?
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Re: Condition of disharge sulfat anions on anode
That I wrote above already
Re: Condition of disharge sulfat anions on anode
Ok. If we will do electrolisis of melted NH4HSO4 (easy melting just 150°C) what we will get SO3 + O or (NH4)2S2O8?