Pierce Nichols wrote: > On Wed, 2003-11-05 at 01:22, John Carmack wrote: > > This may be useful for concentrator work, removing the need for purification. > > I priced it in drum lots when I purchased 50% peroxide for ERPS from > our local Solvay dealer. I do not remember the exact price I was quoted, > but it was in the neighborhood of $2/lb, versus $0.35/lb for the food > grade we actually purchased.
Still, it's good to know that pure stuff (in any decent strength) is available at all... with any continuous-freezing process, there may be limiting issues with solutes concentration. (It's _going_ to lower the freezing point and thus limit the effective extraction fraction; the question is how much, how soon, and with how much other impact on crystallization characteristics... don't know the answer to that one yet.) The stuff we got seems to have fairly low conductivity (even "stabilized"), so it may very well work well - and it would be nice if we could make propellant from such inexpensive feedstock. If solutes buildup turns out to be a big problem, OTOH, then switching to 50% semi grade may well be an effective response. Also, even with an evaporative concentrator, it's going to be difficult to make really high concentrations (independent of solutes issues) - our large-scale sparger trials, so far, seem to indicate a "point of diminishing returns" somewhere around 80%. We see ways to possibly improve things, but I am not abandoning freezing processes yet. -dave w _______________________________________________ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list
