processing rock dust and azomite.

Savannah, GA

I have access to HCL and NAOH, I was thinking of adding the acid to the rock dust, then after a predetermined time, neutralize it with the NAOH. I would think that would hasten the release of the minerals.

what could go wrong? how should I proceed?

Bardstown, KY(Zone 6a)

Plants in general like the slow release of micronutrients. I would apply the amendments as they are and not try to hasten it.


Savannah, GA

Oh what the heck, I'm going to give it a try on an area and see what happens.

Alexandria, IN(Zone 6a)

It might tie up some of the minerals as fancy salts.

Everett, WA(Zone 8a)

Keep in mind that HCl + NaOH combine to form table salt (NaCl). Your soil would not enjoy having tablespoonfuls of salt dumped on it. Those are two chemicals that I would not add to soil, and I'm not the "greenest" guy that ever lived.

Maybe dilute Nitric acid (be VERY careful), followed days later by dolomite lime?
Don't forget that huge amounts of heat are released by diluting or neutralizing acid.
Goggles or a face shield plus gloves.

You know, given the fact of acid rain, rock dust will probably etch itself if you just let it be rained on.

And be sure to neutralize it NEUTRAL. If your plants are showing a micro-nutrient deficiency, it is more likely a pH problem or some other nutirent excess, preventing uptake, than something actually missing from the soil.

That's one reason rock dust is so reliable: it probably won't add anything to excess.

If you really want to blast something with a quick boost of micronutrients, and you aren;t afraid of overdosing or creating imbalances, buy some micronutrient solution, just be sure to dilite it enough.

If the local nursery doesn't have anything concentrated enough for your application, there seem to be many stores lately catering to "indoor grow rooms" with all kinds of soluble nutrients.

You might want to get a soil test first, since some mirconutrients have an optimum concentration range, and 2-3 times the optimum might actually be a little toxic. More is not always better, especially if your soil is already high in something.

Root hairs plus rhizo-bacteria and fungi are pretty good at extracting what they need from rocks, especially rock dust. They produce chemicals that used to be called "humic acids" right at the site of absorbtion.

Little Willy was a chemist.
Little Willy is no more.
What he thought was H2O
Was H2SO4.


Bardstown, KY(Zone 6a)

Good post Corey! Especially the poem....

Everett, WA(Zone 8a)

Thanks. I like science projects, but balancing the risk with the gain is a good idea. I hope margocstn isn;t in the hospital somewhere!

I was in a summer science program when young, and the instructors staged a fake "accident" where someone (apparanetly) added water to a beaker. The heat caused it to crack or foam over and of course he screamed and dove for the emergency shower.

We remembered where the shower was, after that, and:

"Add acid to water, as you oughter."

That way, when it boils and jumps out of the beaker at you, it is less concentrated.

(The year before, someone HAD spilled acid on themsleves, and they had photos of the big "sunburn" caused by dilute acid rapidly rinsed off.

While working at Upjohn, we saw safety videos, one of which dunked a turkey leg into a beaker of concentirated nitric acid. It went down to the bone RATHER quickly.

Savannah, GA

I was pretty good in chemistry and know not to add water to acid, and to neutralize the solution. I even have access to fancy schmancy ph meters, although I will probably just use the ph paper.

I was just going to treat a small amount of rockdust, and dilute it down a bunch. I can even measure how much nacl is in it!

I havn't gotten around to doing it yet, I keep forgetting to bring rock dust to work. I'm going to though . .

Everett, WA(Zone 8a)

It finally occured to me that you could use household ammonia to neutralize acid - at least avoid adding sodium.

Maybe sulphuric or nitric acid would salinize the soil less than HCl, since you know how to take the precautions.

It would be cool to have microphotographs "before and after" etching. Making the surface more porous or corrugated would be beneficial even if the acid did not extract large amounts of soluble micronutirents.

If you have really good balances and an oven, you could wash a sample with distilled water before and after, bake it dry and weigh it before and after, to see if a measurable amount of material was removed. I don't know how to account for adsorbed ions, which might throw off the measurement.

Bardstown, KY(Zone 6a)

Mad scientist Corey....

Everett, WA(Zone 8a)

Guilty, and proud!

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