Altreon
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Registered: 11-12-2025
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Mood: oxidizing
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Isopropyl nitrite, 0% yield?
I tried to synthesize 50g isopropyl nitrite by dropwise addition of half of a frozen mix of 68.2 99% I-PrOH, 20g H2O and 59.5g of 93%
sulfuric acid to a solution of 40g NaNO2 that was kept stirring in an ice bath. Initially, the reaction smelled faintly sweet, but no
visible amount of NOx was produced, nor was there the green/blue color of HNO2. After an initial “runaway” rxn with
formation of a colorless gas, the addition was completed with no problems over the span of 3 hours. I was left with a bubbling salt mass with a
slightly yellow monophasic liquid, with no sign of isopropyl nitrite. There was no significant exothermic reaction, and even after leaving the
solution overnight, nothing separated. What did I do wrong?
I measured the sulfuric acid conc. via density a few days ago. The isopropanol worked well in stoichiometric amounts for various esterifications. The
nitrite is the most sketchy, I recently received the NaNO2 from a chemical supplier and other than confirming the formation of
Co(NO2)63- in a synthesis which also failed, along with the formation of a blue soln./brown gas with HCl, I can’t
say how pure it is exactly.
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Altreon
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Registered: 11-12-2025
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I just now tried using 50% of the remaining mixture with 20g of NaNO2. Even without cooling, no brown gas is produced, only a large amount
of a sweet colorless gas. What is going on?
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Fery
International Hazard
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Registered: 27-8-2019
Location: Czechoslovakia
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Producer/reseller of your NaNO2 and if they are not trustworthy could you validate that it is not something else?
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macckone
Dispenser of practical lab wisdom
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Quote: Originally posted by Altreon  | | I just now tried using 50% of the remaining mixture with 20g of NaNO2. Even without cooling, no brown gas is produced, only a large amount
of a sweet colorless gas. What is going on? |
Sounds like bad nitrite.
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