Thiosulphate Dropped--Testing for PM?

[Mud Dobber]

I am new to this forum. I have been studying the thio leaches for a few years and have learned a lot on this forum. I found a lab study done on this subject.. You may have seen this before, but I think you guys might should check this out....
http://www.ejmpep.com-rath_et.al

The link is broken.

sorry, try it again..I left out pdf.. sometimes my brain seems broken..I put the link on thiosulfate duestions and discussion too

http://www.ejmpep.com/rath_et.al.pdf

 

[chawimac]

It's almost impossible to catch this stuff on a filter (even a very tight, good quality one) as the precipitant is incredibly fine and goes right through until the filter eventually clogs. So we've been draining it off into a heavy glass container, hitting it with 10% hcl to clean, then following up with water to wash again. We let it settle, pour as much fluid off as possible, then slowly cook to dry.

Here's our questions;
Does anyone have a better way of cleaning this product without losing it through a filter? Yes, we can repour the precipitant back through the filter once it clogs, but it's also so fine that it's almost impossible (once it totally dries) to scrape much off the filter. I suppose if we had 4 times the quantity at a time (and we will have once we start doing larger runs) we'll have a lot more on the filter, but that brings up another problem. The filter clogs somewhat fast and by the time there's a thin layer of precipitant on it, it's difficult to get more wash fluid to drain off. So, suggestions on washing, or is what we're doing good enough?

Donno if anyone really answered this question from years ago. I read this thread and maybe I missed in those 181 posts the answer, but I found it a great thread and thought I should contribute.

When you drop something super fine, it usually gets easier the bigger your experiment gets (at least in my opinion). The larger the amount of gold or whatever is precipitating, the greater the probability it clumps together and forms some sort of mass at the bottom of the barrel. What I do, is let it sit for a while (an hour or overnight) and let the reaction finish. As the particles drop they should clump. Care should be taken that things do not re-suspend in solution and that contaminants prevent the dropped particles to gravitate to the bottom (like lead gel or such).

If your chemistry is right things should pretty much happen as I explain, usually. An great option is to siphon you vessel or barrel, and wash your precipitant before the final filtering. Siphoning helps as you reduce volume needed to filter and you get less particles to clog your filter and you are able to remove the majority of liquid before the solids come and clog things up. This is basically the most important advice I can give. Let things settle, siphon, wash, let settle and repeat until final filtering.

Finally, get the right equipment if you can. See my equipment below. I started using pots and pans so been there done that, but the only true way to solve these problems is to use the right equipment and not cut corners. I moved up from coffee filters to a Italimpianti vacuum filter using about a 3 foot diameter filter paper. This filter changed my life, its awesome. You need enthusiasm or deep pockets to have a great experience. For me one lead to the other.