Hi, Dave is working on the freezer to make concentrated HTP out of lower-grade one, AFAIK. The logic, I assume, according to <http://www.h2o2.com/intro/properties/pic11a.gif>, is the following: if you have a 30% (or some other lower grade) HTP, and start cooling it, first the water becomes ice, and only then the peroxide itself freezes. So, at the intermediate state you can remove the liquid, which will represent the higher grade of HTP. If you have peroxide stronger than, say, 65%, the peroxide will freeze first, so you'll get the ice of strong peroxide, which you can then melt to get HTP.
The freezing is preferrable to sparging in that it doesn't encourage you to heat the peroxide to speed up the process; heating is more dangerous than freezing. On the other hand, you have to reach rather low temperatures, like -60F, to make an ice for certain concentrations. An ordinary freezer, AFAIK, can't provide you with such temperature; you're better off with dry ice, but it may have its drawbacks with obtaining, storing, moving, handling etc. Is it possible to use liquid air, or LN2, to reach low temperatures for HTP concentrating by freezing? Or is there some other severe problems on this path? Alex __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com _______________________________________________ ERPS-list mailing list [email protected] http://lists.erps.org/mailman/listinfo/erps-list
