Luke, PEX should work OK, but the life span would depend on what it is exposed to. It is not good for long term outdoor use as UV breaks it down after several months in the sun. Also, it probably won't last too long if used for straight sodium methoxide or high strength sodium hydroxide service, but you may get a few months of continuous service before it fails. I do know that 50% sodium hydroxide breaks it down pretty quick (a couple of months). Heat and pressure will shorten the life further.
It should hold up pretty well to the WVO and biodiesel. An interesting site, biodiesel reactor how to page, listed below shows PEX being used for a sight gauge on his "processor tank". http://journeytoforever.org/biodiesel_processor3.html I also found this: "Joseph, Using polyethylene, cross linked pex tubing is rated for petrochemical use. you will have no problems using it for svo, or biodiesel fuel and processing. It is also rated for pressure and temperature,usually around 200 degress F.and 100 p.s.i. I use it in my business all the time. Good Luck and keep going!! D.Streeter" by searching "PEX" in the lists search engine at the bottom of this page. Here is the link to the page quoted above: http://www.mail-archive.com/biofuel@sustainablelists.org/msg37063.html PEX is basically a crosslinked polyethylene and polyethylene is basically a synthetic wax (chemically like wax) and is pretty resistant to many chemicals and solvents just like wax, but it is no where near as good as teflon or kynar for the straight sodium methoxide, sodium hydroxide. Also the standard 55 gallon plastic drums are made of HDPE (High Density PolyEthylene) which is what some of the PEX tubings are made out of (HDPE). Here is a site with some info on PEX, but I could not find an online chemical resistance chart for it. http://www.ppfahome.org/pex/faqpex.html Also, Nylon is probably even better than PEX. -Mike McGinness WM LUKE MATHISEN wrote: > I have some PEX tubing left over from plumbing our house, any one with > experience using PEX to build a processor? Will the lye react to it? I am > thinking of using it to heat the processor from our tankless waterheater > which we use to heat the floor, as well as for mixing. Also will a washing > machine water pump work? > > Luke > > _______________________________________________ > Biofuel mailing list > Biofuel@sustainablelists.org > http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org > > Biofuel at Journey to Forever: > http://journeytoforever.org/biofuel.html > > Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): > http://www.mail-archive.com/biofuel@sustainablelists.org/ _______________________________________________ Biofuel mailing list Biofuel@sustainablelists.org http://sustainablelists.org/mailman/listinfo/biofuel_sustainablelists.org Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Search the combined Biofuel and Biofuels-biz list archives (50,000 messages): http://www.mail-archive.com/biofuel@sustainablelists.org/
