I have a bottle of this:

 

http://www.nutricology.com/Hydrochloric-Acid-1-500-Liquid-16-fl.-oz.-500mL-p-16674.html

 

I would like to make pure HCL from this. Then make a solution of 37% HCL and water from that.

good luck with that. pure HCl is a very unstable and unpleasant gas.

I thought it was a liquid :/

That is so dilute its not worth your time trying to concentrate it. Use it for the intended purpose.

 

Go to a hardware store and buy yourself some 31.45 % HCl. Its only 5-8$ a gallon. You can even get it in the pool supply section too. Its Muriatic acid.

 

Its a great general cleaner and excellent cleaning rust off of iron and steel.

HCL above ~40% is a gas

That is so dilute its not worth your time trying to concentrate it. Use it for the intended purpose.

 

Go to a hardware store and buy yourself some 31.45 % HCl. Its only 5-8$ a gallon. You can even get it in the pool supply section too. Its Muriatic acid.

 

Its a great general cleaner and excellent cleaning rust off of iron and steel.

 

The bottom of my car is quite rusty. Would this be a good way to get rid of it? Or would it clean the rust off by eating my car?

you can add some Barium or Calcium carbonate or hydroxide to it until the pH is neutral, then evaporate all the liquid off.

then you add the remainder to sulphuric acid, and hey presto, you have Conc HCl.

 

it`s hardly worth the effort, but that`s how to do it if you Really wanted to.

If you have the concentrated sulfuric acid, it would be easier to just dump some common table salt into there and collect the HCl that is driven off.