I am using a nitric bath to etch steel. I have about five litres going. 1 part nitcic:9 parts water.
I read today on the net somewhere that bi carb is okay for cleaning up spills and such but it won’t go a long way to neutralising my acid.

My acid bath is still trucking on pretty well and is still etching hard. So this isn’t urgent problem. The way it is going I should have a month or two more out of it at least.

Anyway..today’s wondering is whether I can run my used etch through rock phosphate and turn it into super phosphate and put it on hydrangeas.

sarahs mum said:

I am using a nitric bath to etch steel. I have about five litres going. 1 part nitcic:9 parts water.
I read today on the net somewhere that bi carb is okay for cleaning up spills and such but it won’t go a long way to neutralising my acid.

My acid bath is still trucking on pretty well and is still etching hard. So this isn’t urgent problem. The way it is going I should have a month or two more out of it at least.

Anyway..today’s wondering is whether I can run my used etch through rock phosphate and turn it into super phosphate and put it on hydrangeas.

Wow. What a good question!

sarahs mum said:

I am using a nitric bath to etch steel. I have about five litres going. 1 part nitcic:9 parts water.
I read today on the net somewhere that bi carb is okay for cleaning up spills and such but it won’t go a long way to neutralising my acid.

My acid bath is still trucking on pretty well and is still etching hard. So this isn’t urgent problem. The way it is going I should have a month or two more out of it at least.

Anyway..today’s wondering is whether I can run my used etch through rock phosphate and turn it into super phosphate and put it on hydrangeas.

It would appear so…not sue about the HF that’s produced though, my chemistry skills are pretty basic…

20HNO 3 + Cal0(PO4)6F2 ——> 6H3PO 4 + 10Ca(NO3) 2 + 2HF

First five second glance at a book I have here: Groggins (1938) “Unit processes in organic synthesis”

It recommends recovering the nitric acid rather than neutralising it.

The process is simple distillation, with the proviso that the distillate passes through water rather than allowed directly to air in order to capture any oxides of nitrogen that may be present.

mollwollfumble said:

sarahs mum said:

I am using a nitric bath to etch steel. I have about five litres going. 1 part nitcic:9 parts water.
I read today on the net somewhere that bi carb is okay for cleaning up spills and such but it won’t go a long way to neutralising my acid.

My acid bath is still trucking on pretty well and is still etching hard. So this isn’t urgent problem. The way it is going I should have a month or two more out of it at least.

Anyway..today’s wondering is whether I can run my used etch through rock phosphate and turn it into super phosphate and put it on hydrangeas.

Wow. What a good question!

Super phosphate is made by using Sulphuric acid. What you would be making would be what is known as nitrophoska https://www.incitecpivotfertilisers.com.au/en/Products/IPF%20%20Products/Nitrophoska%20Special

I’m with poik. Anything I can find on the production of superphosphate by reaction of rock phosphate with acid says that hydrofluoric acid and hydrofluorosilicic acid are products.

http://pubs.acs.org/doi/abs/10.1021/jf60101a002?journalCode=jafcau

mollwollfumble said:

First five second glance at a book I have here: Groggins (1938) “Unit processes in organic synthesis”

It recommends recovering the nitric acid rather than neutralising it.

The process is simple distillation, with the proviso that the distillate passes through water rather than allowed directly to air in order to capture any oxides of nitrogen that may be present.

Distillation..doesn’t sound that simple..

dv said:

I’m with poik. Anything I can find on the production of superphosphate by reaction of rock phosphate with acid says that hydrofluoric acid and hydrofluorosilicic acid are products.

http://pubs.acs.org/doi/abs/10.1021/jf60101a002?journalCode=jafcau

Are you saying that I would end up with activated phosphate and more leftovers I didn’t know what to do with?

sarahs mum said:

dv said:

I’m with poik. Anything I can find on the production of superphosphate by reaction of rock phosphate with acid says that hydrofluoric acid and hydrofluorosilicic acid are products.

http://pubs.acs.org/doi/abs/10.1021/jf60101a002?journalCode=jafcau

Are you saying that I would end up with activated phosphate and more leftovers I didn’t know what to do with?

Well I don’t know that for a fact … I’m saying it seems that is a risk and you should take precautions.

Apparently burying iron with Hydrangeas is a victorian thing to do. Rusty nails and horseshoes and all. But it didn’t make the soils that wouldn’t take up the iron change. It needed aluminium or lime.

“Blue flowers turning pink is a problem most associated with the cultivars of Hydrangea macrocarpa, however it can also be seen to a lesser extent with cultivars of Hydrangea involucrata and serrata. This colour change is due to the soil pH, which most gardeners will associate with ericaceous plants and the effect pH can have on their ability to take up iron and magnesium. In the case of hydrangeas it is aluminium which is the problem element.

For hydrangeas, aluminum becomes unavailable to them under alkaline conditions and aluminium is required so that the plant can produce (among other things) the blue pigmentation in the blooms. Put simply, hydrangeas will flower blue on acidic soils and pink on alkaline soils.

If you have already purchased blue flowering hydrangea then they can be kept blue by growing the plants in acidic soil of between pH 4.5-5. If the soil is not acidic to start with then consider acidifying your soil by digging in plenty of moss peat or ericaceous compost.”

http://www.seedsofeaden.com/ornamental-plants-k7/why-has-my-blue-hydrangea-turned-pink-b285.html

1

Remove mulch, leaves or other ground clutter from the area immediately around the hydrangea.
2

Dig a hole, 6 inches deep and at least 10 inches from the base of the hydrangea plant, with a trowel. Dig carefully so the roots of the hydrangea are not damaged or cut.
3

Place a rusted iron nail, such as a 12D size, in the hole and bury it. The rust increases the dirt’s acidity level around the plant, which causes the plant to take in aluminum more easily from the soil.
4

Dig additional holes around the plant spaced 6 to 8 inches apart. Place a rusted iron nail in the bottom of each hole and cover with dirt. Replace the mulch or ground cover around the hydrangea plant.
http://homeguides.sfgate.com/bury-rusty-nails-soil-around-hydrangea-plants-46820.html

ericaceous eh?

dv said:

ericaceous eh?

heatherish?

roughbarked said:

mollwollfumble said:

sarahs mum said:

I am using a nitric bath to etch steel. I have about five litres going. 1 part nitcic:9 parts water.
I read today on the net somewhere that bi carb is okay for cleaning up spills and such but it won’t go a long way to neutralising my acid.

My acid bath is still trucking on pretty well and is still etching hard. So this isn’t urgent problem. The way it is going I should have a month or two more out of it at least.

Anyway..today’s wondering is whether I can run my used etch through rock phosphate and turn it into super phosphate and put it on hydrangeas.

Wow. What a good question!

Super phosphate is made by using Sulphuric acid. What you would be making would be what is known as nitrophoska https://www.incitecpivotfertilisers.com.au/en/Products/IPF%20%20Products/Nitrophoska%20Special

Haven’t read up on that before. Ta.

Ericaceous soil

sarahs mum said:

dv said:

ericaceous eh?

heatherish?

Ericaceae is the family name for heath plants, which are mostly found in acid soils.

Back to original question, the cheapest way to neutralize it would be drain cleaner, some country hardware stores still stock NaOH for cleaning drains, which is even cheaper and more effective.

Use the free pool pH test strips in your hardware store to check that the result is pH neutral.

mollwollfumble said:

Back to original question, the cheapest way to neutralize it would be drain cleaner, some country hardware stores still stock NaOH for cleaning drains, which is even cheaper and more effective.

Use the free pool pH test strips in your hardware store to check that the result is pH neutral.

Ta. Free pool PH test strips you say..

So it’s OK for the cat to run away and hide when visitors turn up; but when I do I’m antisocial.

sibeen said:

So it’s OK for the cat to run away and hide when visitors turn up; but when I do I’m antisocial.

—

Take 2 quickeze and you will be ok.

sarahs mum said:

mollwollfumble said:

Back to original question, the cheapest way to neutralize it would be drain cleaner, some country hardware stores still stock NaOH for cleaning drains, which is even cheaper and more effective.

Use the free pool pH test strips in your hardware store to check that the result is pH neutral.

Ta. Free pool PH test strips you say..

Bunnings has them for free. Not so sure about other hardware stores.

I took some to test the water in a creek in a public park after noticing that all the vegetation was avoiding drinking from the creek, which turned out to have a pH exceeding 10.

mollwollfumble said:

sarahs mum said:

mollwollfumble said:

Back to original question, the cheapest way to neutralize it would be drain cleaner, some country hardware stores still stock NaOH for cleaning drains, which is even cheaper and more effective.

Use the free pool pH test strips in your hardware store to check that the result is pH neutral.

Ta. Free pool PH test strips you say..

Bunnings has them for free. Not so sure about other hardware stores.

I took some to test the water in a creek in a public park after noticing that all the vegetation was avoiding drinking from the creek, which turned out to have a pH exceeding 10.

oooo. :(

Get some ammonium and mix it with the nitric acid

I reckon that would be ammonium nitrate – fertiliser

• Get some ammonium and mix it with the nitric acid

Don’t use acetone though…

wookiemeister said:

Get some ammonium and mix it with the nitric acid

I reckon that would be ammonium nitrate – fertiliser

um, don’t do that, the reaction can be rather ‘unpleasant’ to be near.

furious said:

• Get some ammonium and mix it with the nitric acid

Don’t use acetone though…

Peroxide and acetone ( don’t snort the crystals)

poikilotherm said:

wookiemeister said:

Get some ammonium and mix it with the nitric acid

I reckon that would be ammonium nitrate – fertiliser

um, don’t do that, the reaction can be rather ‘unpleasant’ to be near.

I wasn’t going to…
(but thanks for checking…)

sarahs mum said:

poikilotherm said:

wookiemeister said:

Get some ammonium and mix it with the nitric acid

I reckon that would be ammonium nitrate – fertiliser

um, don’t do that, the reaction can be rather ‘unpleasant’ to be near.

I wasn’t going to…
(but thanks for checking…)

Errrrr

You use plenty of water……..

Anyone would think buffy was making pipebombs, painstakingly making pipebombs, fastidiously filing, cleaning, packing powder; methodically twisting the metal heads on with stained fingers under the gaze one lone swinging lightbulb and a postman that knew too much.