Yeah, although KClO4 also suffers the same exponent issues as common xClO3s
although not hygroscopic and NaClO3 (like your experience) was very workable;
it just caught Paul by surprise at how little was required. Intuitively, it’s
easy to imagine that the much lower energy content of chlorates would
compensate for the effects of the increased exponent, but the ignition of U/C
valve hybrids can be a particularly violent affair for a single port injector
when you’re momentarily getting nitrous being injected from both your tank and
fill line.
Yeah, done lots of perchlorate production over the last 20+ years too –
mostly with lead dioxide anodes though and I agree it’s basically just extra
time *if* you have the right anode materials which are commonly sourced and
cheap for chlorate production, but not so common or cheap for perchlorate
electrolysis.
Troy
From: arocket-bounce@xxxxxxxxxxxxx [mailto:arocket-bounce@xxxxxxxxxxxxx] On ;
Behalf Of Marcus D. Leech
Sent: Tuesday, 7 August 2018 10:13 AM
To: arocket@xxxxxxxxxxxxx
Subject: [AR] Re: More on NaClO3
On 08/06/2018 07:28 PM, Troy Prideaux wrote:
Also worth noting: Paul Kelly was looking for an N2O hybrid preheater grain
propellant that utilised an oxidizer he could make himself easily. I suggested
NaClO3+Epoxy as an option as it was shortly after I went through testing that
stuff in solids and I had an old electrolysis cell to offer to get him started.
After a few amazingly spectacular casing->shrapnel conversions, it was soon
abundantly clear that the amount of propellant required for the preheater grain
was only a small fraction of what we required for APCP as the exponent really
kicked in with a U/C valve N2O hybrid ignition - well beyond our expectations.
Troy
When I was using pre-heaters, I used KClO4+Epoxy grains--fairly thing slices.
No kablooeys as a result.
Once you're setup with a Pt-based cell, there's no reason not to produce KClO4.
From: arocket-bounce@xxxxxxxxxxxxx <mailto:arocket-bounce@xxxxxxxxxxxxx>
[mailto:arocket-bounce@xxxxxxxxxxxxx] On Behalf Of Troy Prideaux
Sent: Tuesday, 7 August 2018 8:58 AM
To: arocket@xxxxxxxxxxxxx <mailto:arocket@xxxxxxxxxxxxx>
Subject: [AR] Re: Cheap Solids? Amonium Nitrate: catalysis vs sensitization
Mark,
I didn’t really have a problem with the tiny grains – or at least in the
boiler plate motors I tested them in. Well, I cracked a few graphite nozzles
from over pressuring but can’t remember experiencing anything significant until
I started scaling up – which was also accompanied by more adventurous fuel
experimentation – a methodology and practice doomed for nasty surprises.
I agree that the exponent is manageable *IF* you’re really disciplined with
the development. The margins for experimenting with different fuels or
additives or processing techniques than what you’ve already proven is a lot lot
tighter than a typical APCP. Issues with porosity or binder wetting or
structural integrity with the propellant will be magnified exponentially.
Which is not to suggest there’s no place for trying different fuels or
whatever – just that you need to be extra careful about thorough
characterization 1st with tight controls on maintaining what’s been
characterized to be workable when scaling up.
Troy
From: <mailto:arocket-bounce@xxxxxxxxxxxxx> arocket-bounce@xxxxxxxxxxxxx [
<mailto:arocket-bounce@xxxxxxxxxxxxx> mailto:arocket-bounce@xxxxxxxxxxxxx] On ;
Behalf Of Mark C Spiegl
Sent: Saturday, 4 August 2018 1:10 AM
To: <mailto:arocket@xxxxxxxxxxxxx> arocket@xxxxxxxxxxxxx
Subject: [AR] Re: Cheap Solids? Amonium Nitrate: catalysis vs sensitization
The exponent is the issue with these oxidizers.