Sciencemadness Discussion Board

sulphur trioxide and water

Little_Ghost_again - 10-10-2014 at 07:35

On reading it seems if I try and heat sodium bisulphate then I get sodium trioxide.
But if I bubble this into water it goes mad and forms a mist of sulfuric acid.
So..............
Is it possible to have a glass water bath with one of those gas things like a upside down flower pot and a gas jar half full of air on top. Bubble the trioxide into the water under the gas jar and trap the mist?
If I bubble the gas slow enough would the sulfuric mist mix with the water in the gas jar?
I am looking for a easy way to make sulfuric acid without using hydrochloric etc.

Or old batter thats dead, weak sulphuric from that and bubble as per set up above?

Amos - 10-10-2014 at 08:04

Do you mean sodium bisulfate or bisulfite? I haven't heard of the first one decomposing that way.

Firstly, I would suggest buying it if you can(unless you're just making it for chemistry's sake); you're likely to be using it for so many things later on that you'll need more than you can likely make.

Secondly, sulfuric acid can indeed be using sulfur trioxide, but this is usually done in the industry by dissolving it in already concentrated sulfuric acid to create oleum(fuming sulfuric acid), and then water is added to react with the sulfur trioxide in solution without any gas phases getting in the way.
It can also be made by bubbling sulfur dioxide, readily made from bisulfite or metabisulfite into hydrogen peroxide, with a low yield.

Depending on how much research you've done, you might've known all that, but I thought I'd chip in.

Metacelsus - 10-10-2014 at 08:10

What's done in industry is absorbing the SO3 in concentrated sulfuric acid to make oleum, and then adding water to the oleum. Direct reaction of SO3 with water is too violent.

Honestly, I'd just stop at the oleum, as it is harder to get than sulfuric acid.

Sorry, didn't notice No Tear's post.

[Edited on 10-10-2014 by Cheddite Cheese]

Amos - 10-10-2014 at 08:12

Quote: Originally posted by Cheddite Cheese  
What's done in industry is absorbing the SO3 in concentrated sulfuric acid to make oleum, and then adding water to the oleum. Direct reaction of SO3 with water is too violent.

Honestly, I'd just stop at the oleum, as it is harder to get than sulfuric acid.

[Edited on 10-10-2014 by Cheddite Cheese]


Dude, trying to steal my spotlight?

AsocialSurvival - 10-10-2014 at 08:35

Yes, you can make Sulfuric acid by vaporizing Sodium bisulfate and condensing it into water. There may be some mist, heat, and even splashing because SO3 reacts exothermically with water. But, after some time everything will cool down and you're done.

Practically imagine all bi-salts as acid + that salt. Bisulfate is mixture of sulfate and sulfuric acid. You're just boiling or decomposing sulfuric acid in this case.

Altough I prefer nuclear fusion, if you put extremely high heat and pressure on Oxygen, you will get Sulfur in unlimited quantities.

O + O => S

[Edited on 10-10-2014 by AsocialSurvival]

Little_Ghost_again - 10-10-2014 at 10:59

Hmm sounds like a lot of agro for little gain.

Back to messing with copper

Praxichys - 10-10-2014 at 11:13

Quote: Originally posted by No Tears Only Dreams Now  
Do you mean sodium bisulfate or bisulfite? I haven't heard of the first one decomposing that way.

Bisulfate decomposes to pyrosulfate and then SO3.

Bisulfite does not. Perhaps you have confused this with metabisulfite, which decomposes releasing SO2?

Little_Ghost_again - 10-10-2014 at 11:23

I have no idea now as i have totally confused myself! I will go check :D

Amos - 10-10-2014 at 12:11

Quote: Originally posted by Praxichys  
Quote: Originally posted by No Tears Only Dreams Now  
Do you mean sodium bisulfate or bisulfite? I haven't heard of the first one decomposing that way.

Bisulfate decomposes to pyrosulfate and then SO3.

Bisulfite does not. Perhaps you have confused this with metabisulfite, which decomposes releasing SO2?


I haven't worked with it before, so I can't tell for sure, but from Wikipedia: "sodium bisulfite releases sulfur dioxide gas when added to water or products containing water." I didn't know if he meant heating it while anhydrous or while in water, as is often done with metabisulfite. I know he said trioxide and not dioxide, but sulfur dioxide is more commonly used to produce sulfuric acid by amateur means as far as I've seen.

macckone - 10-10-2014 at 14:51

Depending on the depth of the water and speed of gas generation, it is possible to dissolve sulfur trioxide in water.
However you should probably try sulphur dioxide using
the chamber method first. As the above procedure can
go badly in an explosive manner. Think sulfuric shower.

blargish - 11-10-2014 at 12:54

Yea, bubbling sulfur dioxide through an oxidizer is a MUCH easier method of obtaining sulfuric acid than trying to make it via SO3. However, if you are trying to make SO3, another approach is to thermally decompose a persulfate salt with a little bit of concentrated sulfuric acid as catalyst.

Little_Ghost_again - 11-10-2014 at 13:00

Its definitely the one you heat and get trioxide.
So if I do I need maximum containment, ok I need to think about this before trying. maybe gas jar of water upside down in tank of water then bell jar over all of that.
Hmm drugs kicking in (prescribed)

Texium - 13-10-2014 at 19:22

Quote: Originally posted by AsocialSurvival  
Altough I prefer nuclear fusion, if you put extremely high heat and pressure on Oxygen, you will get Sulfur in unlimited quantities.

O + O => S
Can you U2U me with some further info about this process? I am very intrigued.

macckone - 14-10-2014 at 17:29

Quote: Originally posted by zts16  
Quote: Originally posted by AsocialSurvival  
Altough I prefer nuclear fusion, if you put extremely high heat and pressure on Oxygen, you will get Sulfur in unlimited quantities.

O + O => S
Can you U2U me with some further info about this process? I am very intrigued.

You need one of these reaction vessels
en.Wikipedia.org/wiki/star

Jstuyfzand - 16-7-2016 at 14:35

Quote: Originally posted by macckone  
Quote: Originally posted by zts16  
Quote: Originally posted by AsocialSurvival  
Altough I prefer nuclear fusion, if you put extremely high heat and pressure on Oxygen, you will get Sulfur in unlimited quantities.

O + O => S
Can you U2U me with some further info about this process? I am very intrigued.

You need one of these reaction vessels
en.Wikipedia.org/wiki/star


Should be doable, got something to do for the weekend now.

careysub - 17-7-2016 at 09:21

On another note. The "little_ghost" persona has not posted in 6 months.

Perhaps this serial liar has finally left us in piece?

clearly_not_atara - 17-7-2016 at 14:33

SO2 IIRC has pretty good solubility in GAA; I wonder if that could be used as a way to increase the yield (using 30% H2O2 and SO2 at low temp):

http://www.orgsyn.org/demo.aspx?prep=CV7P0508

Not sure how easy it is to separate H2SO4 from HOAc though...