Can this be used to power my airbrush

Oh My ! I like Owls !

 Now that said,I have to concur with G.Morrison on this .You'd be better off getting the compressor. If you have to do it on the cheap go to Harbor freight and get the Air Tank used for autos .I used one for years when I was R.Ving . I had a moisture trap and regulator on it and it worked just fine .Just remember to keep it full and after a long use purge it with the drain valve to clear the tank of moisture that settles in the bottom. Other that that I only had at that time forty Bucks total invested .

    With what prices are today maybe you'd be better spending the cash and getting a compressor from Harbor Frieght.They do sell the hobby sized W.R.Brown product there, and Mine ( before it took an unscheduled walk) was over fifteen years old and still going strong .

It will end up costing you much more than a compressor. Also, if a 20lb CO2 tanks lasts 6-8 hrs, I can't imagine a soda stream cartridge lasting more than 1 or 2.

Not sure if a regulator intended for air will work with CO2 or not.  Anyone know?  If it can, air pressure regulators are not that expensive- ten to fifteen bucks.  Compared to price of a compressor, that would make it worthwhile- and fittings are not expensive.

Yes, in the loosest sense they will "work" but not well and with no control over the pressure. By the time you get a regulator, fittings and whatnot you will wonder why you tried this in the first place.