ethanol is a decent solvent for thc...and it dissolves lots of water soluble chemicals that don't get you high, but give flavour. isopropyl is not as good a solvent, and has a funny flavour imo.
acetone is a better solvent for thc (it gets more out of the plant), and dissolves less water soluble crap so it's purer.
petroleum ether is the best thc solvent, and doesn't pick up water soluble crap...so the most thc, and purer.
'butane' is really a butane and propane mix. petroleum ether/naphtha is a mix of heavier hydrocarbons. it's found in camping fuel. it's NOT water soluble, so you can get the bulk of the solubles out with ethanol, and grab mostly thc with naphtha...just drain off the ethanol.
you can boil off the liquid at room temperature by lowering the pressure. perhaps a food sealer may work, or an industrial vacuum pump.
http://www.fibreglast.com/product/Vacuum_Bagging_Starter_Kit_02229_A/Vacuum_Bagging_Pumps
applying heat to evaporate liquid will quickly denature thc. once thc is outside of a trichome it quickly oxidizes.
imo, if you have kif, just keep sifting with finer mesh until you get blonde.