Is This Sodium Carbonate?

[ASA1000]

I mix 54-D developer for prints.Its pretty basic: Metol, Sod Sulphite, hydroQ. Sodium Carb and 10% KBI
Doing this for many years. Mixed well etc. Yesterday I mixed a half gallon, made prints all day. Everything was 100% normal.
This morning I go to pour out some developer from the batch I mizxed yesterday and it comes out 'clumpy' with a silver precipitate in suspension.
Only thing I can think of is I'm using a different supplier for the Sodium Carbonate.
I tried stirring, diluting with hot water.. nothing made a difference.
I'll get some fresh Sod Carb. from the Formulary and try again but while I'm waiting, has anyone seen this? or is the some clue that might give away what's happening or how to save it (;-)?
Thx!
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[xkaes]

Is it MONOHYDRATED? You might have deca-, hepta- or anhydrous. What does the container say?

[ASA1000]

It doesn't say. It is a pool supply product. But the latest part is, when I diluted it with COLD water (it was room temp overnight) but when I diluted it with 50-degree Colorado water it dissolved almost completely and I have made a few test prints which seem to be OK.
What's the 'deal' with the mono/anhydrous etc. Is that it?
Thx

[xkaes]

The prefix indicates how much water the chemical has in it. Monohydrated is what's commonly used in photography. I have no idea what a "pool supplier" stocks

Different hydrates of sodium carbonate refer to different forms of sodium carbonate where a varying number of water molecules are chemically bound to the sodium carbonate molecule, with the most common hydrates being sodium carbonate decahydrate (Na2CO3·10H2O), sodium carbonate heptahydrate (Na2CO3·7H2O), and sodium carbonate monohydrate (Na2CO3·H2O); essentially, each hydrate contains a different amount of water molecules attached to the sodium carbonate molecule, impacting its physical properties like solubility.

The type you were using might be more likely to precipitate out.

[teathomas]

The kind of sodium carbonate sold for increasing the pH of swimming pools is not a good choice for photo chemistry. The MSDS lists as low as 60% sodium carbonate and does not list the other chemicals. So who knows what you've got floating in your beaker.

[ASA1000]

The kind of sodium carbonate sold for increasing the pH of swimming pools is not a good choice for photo chemistry. The MSDS lists as low as 60% sodium carbonate and does not list the other chemicals. So who knows what you've got floating in your beaker.


Package says 100% pure sodium carbonate but nothing more.

OK clearly this is the problem. Thanks!

[reddesert]

I don't think the amount of hydrates - anhydrous, mono, deca, etc - is going to take part in the chemical reaction - it's just water that should go into solution when you dissolve the material. What could matter is the measurement. For example 10g of sodium carbonate monohydrate contains more sodium and carbonate ion, versus 10g of sodium carbonate decahydrate, because the decahydrate has a lot of water locked up in it. So even if your material is pure, your recipe may come out different depending on the amount of hydration.

[Jason Greenberg Motamedi]

If you are looking for cheap, try "washing soda" or even "soda ash." This is typically technical grade sodium carbonate decahydrate, and in my experience adequate for some photographic purposes, like paper developer. I have an bucket of Arm & Hammer Washing Soda (20+ years old) which has served me well. Some information here: https://caffenol.blogspot.com/2010/03/soda-myth-and-truth_07.html

[xkaes]

There are various ways to cut down on your chemical costs.

First, mix your own chemicals instead of buying the prepackaged kind. You'll need to buy a level to measure the chemicals, but this will pay for itsself in no time.

Second, but in bulk. Most chemicals will last forever if properly stored. But read the label first; it will tell you if the chemical is subject to oxidation or has special storing requirements. Normally, freezing or refrigerating the chemical will NOT increase its longevity, as with film. I once bought a 50 pound bag of sodium sulfite for $20. A one pound bottle from Kodak was priced at $7. The bottle would have lasted a few months, the bag is still going strong after ten years!

Third, buy used. A lot of people set up a darkroom and, for one reason or another, decide it is not their cup of tea. They then sell their equipment and chemicals in the newspaper or to the local used camera shop. You can get these chemicals for a song. I regularly pick up half-filled bottles of Kodak Indicator Stop Bath for a quarter at the local used camera shop. To get it new would cost eight times as much! I once picked up a five pound bottle of Kodak metol -- enough for a lifetime -- for $10. To get a new bottle would cost well over $100. Just be cautious will used chemicals. If they are past their expiration date, don't buy them. But it's hard to go wrong if the price is right.

Fourth, buy the lowest grade that you can. Chemicals come in a variety of purity levels -- from extra pure (for scientific tests) to technical grade (perfect for most photographic use). The lower grades have slightly more impurities, but these are not enough to affect photographic outcomes -- and they are a LOT cheaper. You might need to shop around to find certain chemicals in the technical grade, but the search will pay off bigtime.

Fifth, go to the grocery store and pharmacy. A wide variety of chemicals are available at grocery store, home improvement stores and drug stores. Keep your eyes open and read the labels. Often you can find the same chemical that you buy at the chemical supplier, but in a more dilute form.

Ammonia. You can get this at a 28% variety for the chemical supply house or in the 9% variety at the supermarket. It's a LOT cheaper. Make sure you don't get any variety that "suds". Get the one that is just ammonia and water. You'll have to change your formula slightly if it calls for 28% ammonia. For example, if you need 10ml of 28%, use 30ml of 9%.

Borax. You can get this in the soap aisle at the grocery store -- Twenty Mule Team Borax. It's the same stuff you pay ten times as much for at the chemical store. It's best to take it out of the box and put it in an air tight container. A clean one-gallon plastic milk jug should work fine.

Sodium Carbonate. The monohydrated version is used in many formulas, but a cheaper decahyrated version is available in the supermarket, called Arm and Hammer Super Washing Soda. If the formula calls for 1 gr of monohydrate use 2.33gr of decahydrate instead. It's best to take it out of the box and put it in an air tight container. A clean one-gallon plastic milk jug should work fine.

Sodium Hydroxide. Red Devil Lye, available at any grocery store, is the same thing -- and a LOT cheaper.

Aluminum Sulfate. Available as "cake alum" in many stores.

Denatured or Isopropyl Alcohol. Get it at the local drug store in a 70% variety. If your formula calls for 10ml of the 91% type, add 13ml of the 70% solution.

Ethyl Alcohol. Get it at the local liquor store. Buy a bottle of Everclear.

Hydrogen Peroxide. You can get this at the pharmacy in a 3% solution for about fifty cents.

Citric Acid. Available at many drug stores.

Magnesium Sulfate. Same as Epsom Salts available at all drug stores.

Sodium Chloride. Same as table salt. Just make sure you get the kind without iodine added.

Sodium Bicarbonate. Same as Baking Soda.

Cupric (copper) sulfate. Check out the drain cleaners at your local home improvement store.

[jnantz]

great list!
be advised sometimes getting washing soda from a pharmacy is insanely expensive
years ago I was in France visiting family and I searched everywhere for cheep chemistry
pool / spa store was supposed to sodium thiosulfate but didn't ( luckily in Montbeliard there was ilford chemistry for sale at a corner photo store )
grocery stores had sodium bicarbonate but no sodium carbonate so I went to local pharmacy,
a slug of washing soda cost me $30 or more, it would have been more cost effective if
I bought ramen hammer baking soda and just cooked off the water to convert it from bi carbonate to carbonate ...
I still have the slug it came in and keep it just to remind myself not to do that again ...
grocery store had "old gringo" instant coffee, probably the bestest instant coffee I have ever used for caffenol.
it was cheep too ...

[Doremus Scudder]

Package says 100% pure sodium carbonate but nothing more.

OK clearly this is the problem. Thanks!

Don't jump to conclusions too quickly...

Any form of sodium carbonate will work fine for photo chemistry as long as you adjust the amounts depending on the level of hydration. Even if you use the monohydrate amount for decahydrate, you'll just be using a bit less carbonate than the formula requires. This is nothing that would cause a precipitate. Frankly, I don't see a reason for carbonate that has been successfully dissolved to precipitate out at all unless there were a significant temperature drop or if you used way too much carbonate in your formula inadvertently.

The issue of possible contaminates is different; you may have something that isn't really carbonate in your pool chemical, since purity is not such a bit issue in that application. That said, I've used pool carbonate before with no problems.

So test a bit. Mix up a bit of the carbonate separately and see if there are particulates or a precipitate later. (Keep track of volumes and you can use the test solution later if all is well.) Try filtering your developer and see if that helps. Make a few prints with the "clumpy" stuff and see what the results are.

Best,

Doremus

[ASA1000]

Great list. Thanks.

[ASA1000]

Thanks everyone for the help!~

[ASA1000]

Don't jump to conclusions too quickly...

Any form of sodium carbonate will work fine for photo chemistry as long as you adjust the amounts depending on the level of hydration. Even if you use the monohydrate amount for decahydrate, you'll just be using a bit less carbonate than the formula requires. This is nothing that would cause a precipitate. Frankly, I don't see a reason for carbonate that has been successfully dissolved to precipitate out at all unless there were a significant temperature drop or if you used way too much carbonate in your formula inadvertently.

The issue of possible contaminates is different; you may have something that isn't really carbonate in your pool chemical, since purity is not such a bit issue in that application. That said, I've used pool carbonate before with no problems.

So test a bit. Mix up a bit of the carbonate separately and see if there are particulates or a precipitate later. (Keep track of volumes and you can use the test solution later if all is well.) Try filtering your developer and see if that helps. Make a few prints with the "clumpy" stuff and see what the results are.

Best,

Doremus

You touched on temperature. Let me add this: I mixed it up in as hot water as the tap provided. Definitely over 125, then it cooled overnight in a glass bottle on the concrete basement floor - probably a little below 68 degrees. Then there is the fact that wen I diluted it the following morning first with 125-degrees 1 to 1 and then afterwards another 40mm but this time 50-degree tap cold IT DISOLVED and I used the batch and it worked fine. So I think you're on to something with the temperature. Thanks for that! Now I gotta get the meat thermometer to see how hot the hot water gets.

[jnantz]

the caffenol blog Jason linked you to on a deeper dig has info in the dissolving of washing soda. some of the folks in the caffenol-mafia used to mix the washing soda and let it sit overnight and because mixed warm or cold, it sometimes doesn't completely dissolve.

[ASA1000]

the caffenol blog Jason linked you to on a deeper dig has info in the dissolving of washing soda. some of the folks in the caffenol-mafia used to mix the washing soda and let it sit overnight and because mixed warm or cold, it sometimes doesn't completely dissolve.

Thanks! I read that twice and now I have to cook some up to see what I've got. I ordered some anhydrous and I'll be curious to see a side by side development test. I suspect, as long as it's all dissolved, it will be the same.... but I have suspected in error in the past!