With a few plumbing supplies, you can put together an inexpensive water distiller you can use on your stove, rocket stove, or campfire. The video below shows you how one man has made a homemade water distiller for water purification.
Be sure to read the cautionary notes below.
Here are a few words of caution to keep in mind.
Don’t use a plastic collection vessel. It will melt or warp. Don’t touch the copper pipe because it gets very hot.
It’s also not recommended to seal this apparatus. some water vapor needs to escape or high pressure would build up very fast.
Also note that the larger the glass jar you use, – the larger amount of water vapor you can collect (at a given time).