BromicAcid - 30-9-2003 at 17:28
It sounds stupid at first but there is a little bit more to it. Im using it as a reducing agent and in order to lower the reaction temperature as low
as possible I need a very very fine sand, like 325 mesh or 2 - 3 micron. Like fumed silica but I'm having trouble finding sources for it. Also
I would perfer it to be anhydrous not like silica gel although I could dehydrate it first. Finally I do not want to pay $13 for 100 grams like
spectra wants. I mean, I just bought 50 lbs for $1.75 (yes, I could sift out the fine grain sand until I have enough and dehydrate it at high temp
but I'm kinda lazy sometimes so I'm going to the internet for a reliable product, plus I believe anything close to 325 mesh has been removed
because it might cause silicosis, it is play sand afterall) so it just seems terrible to pay that much. So in summation, I want to be able to buy a
managable quantity of fairly pure sand of extrememly small grain size and not the silica gel type used to absorb water.
Thanks in advance for any help on this somewhat lame question!
Polverone - 30-9-2003 at 18:00
Check out a place that sells ceramics supplies. I've seen ~300 mesh dry silica from them.
Haggis - 30-9-2003 at 18:12
Two things I can think of are refills for existing products. One is stuff for 'sand art' it is very fine. It has been 9 years since my
grandma gave me a 'sand art' kit for my birthday, but I believe that the sand is very fine. Also, another source that I am almost positive
of is this: I am not sure how to describe it, but it is a pendulum on a stick...when you push or pull the pendulum, it drags the tip through the
extremely fine silica in the tray below it. The pendulum setups are usually sold in places like 'Gadzooks' in American malls. I am sure
you can get a replacement bag of sand from these manufacturers. However, I am not sure of the price.
SiO2 source
Mr. Wizard - 30-9-2003 at 20:49
I was thinking about making some sodium silicate by fusing sand and sodium carbonate. I gave some thought to using diatomaceous earth as the silica
source. It is readily available through swimming pool supply sources, used as the filter media in some cannister filters. Silica Sand is also
available in lumber yards, but it does contain other impurities. Look for it around the cement, and masonry supplies. It is often used for sand
blasting. Don't breath the dust.
SiO2 atomization
axehandle - 8-1-2004 at 10:34
Can't find a small enough mesh size? I would
suggest using a ball mill with stainless steel
balls as the milling media.
BromicAcid - 8-1-2004 at 11:12
I eneded up getting fumed silica used for concrete. It has about the smallest particle size I could finde and it is fairly cheap by this method.
100g is very nearly 1 L in volume
! Plus I don't have to worry about it
having abosrbed any water as the jar very clearly says anhydrous (and also that it's incredibly deadly).
vulture - 8-1-2004 at 15:19
If you're really desperate you could always burn silicone glue.
chemoleo - 8-1-2004 at 16:50
yepp, that works very nicely. Make sure you collect the white fumes too, and allow a nice heat to develop with plenty of air, so that there are no
carbon deposits.
I did it once with the silicone stuff that is used to seal windows to the frame, or seal things in kitchens, labs etc.
chemoleo - 11-1-2004 at 17:36
They also sell quartz sand, or dust, in various sizes at www.kremer-pigmente.de. They do international shippings... so a good opportunity to buy additional useful items 