Using Sulfur Trioxide

[imp]

What is an acceptable procedure to use SO3 to make Sulfuric Acid? What proportions would result in reasonably concentrated acid? imp

[insane_alien]

dissolving it in water usually works.

 

how concentrated is 'reasonably concentrated' 1mol/l 10mol/l 0.1mol/l what?

[YT2095]

SO3 doesn`t dissolve in water very well, you need to dissolve it in H2SO4 to make Oleum, and then you can add it to water.

[imp]

dissolving it in water usually works.

 

how concentrated is 'reasonably concentrated' 1mol/l 10mol/l 0.1mol/l what?

 

What I would like is to have a B.P. of about 300C. imp

[imp]

SO3 doesn`t dissolve in water very well, you need to dissolve it in H2SO4 to make Oleum, and then you can add it to water.

 

My Chemistry text claims SO3 is mixed with water to make H2SO4. I sort of questioned that in my mind, so posted this. (The text: General Chemistry, by March & Windwer). I wondered if there were truth in this, why would the commercial processes used to produce H2SO4, as involved as they are, be used at all?

 

I thank you for your input! imp

[Comandante]

Commercially, contact process is used. Sulfur trioxide appears in the contact process, however it is converted to oleum first before reacting with water to give sulfuric acid, as YT said. I don't recall any texts where SO3 reacts directly with water to give sulfuric acid, though it doesn't sound too fantastic, perhaps it can work?

[YT2095]

"Oleum is an important intermediate in the manufacture of sulfuric acid. If mainly due to its high enthalpy of hydration when SO3 is added directly to water, rather than simply dissolving, it tends to form a fine mist of sulfuric acid which is difficult to manage. If SO3 is added to concentrated sulfuric acid instead, it dissolves readily forming oleum which can then be diluted with water to produce additional concentrated sulfuric acid."

 

taken from: http://en.wikipedia.org/wiki/Oleum

[Comandante]

Interesting. The question is: how difficult is it to manage it?