I blasted some BHO from some trim I had hanging out in one of my jars. I let all the initial liquid butane to evaporate off then added about 500ml of 91% isopropyl alcohol. This has two reason, one it allows the rest of the butane in the oil to be released without the need for an extended vacuum process and second it allows me to run it thru a vacuum flask to filter out any large contaminates and from what I've read the larger fats and waxes that are still in the oil. In the end it should make a higher quality eliquid for my V2 pen vape.
Here's how it looked after being vac filtered
Here's what all got filtered out in the end