Is there a Chemist in the house?

RobertP

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I just received a 1 liter bottle of formaldehyde 37%. There is a sediment that is settled in the bottom. Is this normal? Should I just use the clear liquid that is on top or should I shake and mix the sediment into the solution? Apparently the sediment is not going completely into solution. Does this mean that the solution is already to saturated and won't allow all the particles to dissolve? I'm using this as a hardner for Gum. Any help would be appreciated
 

John_Brewer

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No, you shouldn't have anything at the bottom. Formaldehyde is actually a gas at 20 deg C, you have 37% formaldehyde solution, sometimes called Formalin (a trade name). The fumes are dangerous as well as unpleasant so don't try and filter it, certainly not outside of lab conditions. I'm guessing from you posting in the alt process forum you're using it to harden gelatine sizing. I would pipette off what you need as and when just leaving the sediment.
 
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Robert,

Go to the nearest tool rental place (United Rentals, or whatever you have near you) and get a good half face respirator and also the cartridges that are suitable for formaldyhide if you don't have one already. The cartridges are good for about 3 hours. I write on the cartridge the total time I have it on so I know when to replace.

As John says, formaldehyde is a gas, so the sediment is not what you want, and it is probably nothing to worry about as long as there isn't too much of it. Pour off the top or pipette from the top and you'll be fine. I poured a bit into a bottle with a dropper and use it that way.

One time using that stuff with a mask will convince you to get one...

---Michael
 
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RobertP

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John, Yes very unpleasant indeed. I'm using a respiratory and I'm gloved when handling it. The darkroom is very well ventilated with a good filtered fresh air supply. So I'm pretty comfortable working with it. You are also correct as to hardening the sizing. My question is.. what is the sediment? If it not suppose to be there then should I even consider using it? Thanks
 
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RobertP

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Michael, I'm using a double cannister half face respirator. But I didn't realize that there are special cartridges for formaldehyde and that they last only 3 hours.The cartridges that are in mine are: R51A chemical cartridge for organic vapors. The paper work that came with the cartridges is long gone so I'm not sure if they are rated for formaldehyde gas so I'll replace them. Thanks, Robert
 
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vanspaendonck

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RobertP

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I think the proper cartridge is the R60A cartridge for formaldehyde. I'll replace the R51A. I'm all for good lab practices.
 
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RobertP

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vanspaendonck, I imagine some of those old timers working with embalming fluid, worked in it up to their elbows without proper protection. I'll be careful and get the right cartridges for the respirator. Plus I'll stop using it when I need glasses. Thanks for the heads up. Robert
 

Gerald Koch

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After a period of time the formaldehyde in solution polymerizes to a substance known as paraformaldehyde which is insoluble in water. This is the sediment that you have noticed.

When I was in high school most everyone had to take biology and dissect a dead frog. The classroom reeked of formaldehyde, bo one died. Unfortunately, today, everyone is afraid of chemicals (stage director, please insert creepy music here). Nothing is kept in perspective.

The last MSDS that I read said that formaldehyde was a possible carcinogen. While it is irritating in higher concentrations, it should be safe for occassional use for photographic purposes such as hardening baths.

I wonder if the EPA ever did a followup study on morticians to see if there was any increase in cancer with members of that profession.
 
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RobertP

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Gerald, I just spoke with a scientist at Fisher Scientific and he said the exact same thing, that formaldehyde polymerizes to a substance known as paraformaldehyde which will never go back into solution. He said that this is usually accelerated by improper storage. A warehouse where the temp has dropped below 20C (I think that was the temp he cited) will cause this almost immediately. I asked what he would recommend and he said "dump it, it is no longer a 37% solution because of the polymerization" I called Science Lab Chemicals and Laboratory Equipment Co. in Houston, Texas and they refuse to make good on the purchase. They also didn't ship it Hazmat like they should. And some of the formaldehyde leaked around a cap that wasn't properly sealed.(no inner seal inside the cap). It is scary to think these people are handling these types of chemicals so unprofessionally. I guess I'm out the price of a liter of formaldehyde. But just a warning to others not to buy from these people. Fortunately here in the small town where I live the local pharmacist said he will order the formaldehyde for me.
 

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Robert,

If you want to push it with Science Lab Chemicals, you could let them know you expect a full refund otherwise you will report them to the shipper for improperly shipping hazardous materials. If they're smart, they'll avoid the hassle and return the money you are owed.
 

Photo Engineer

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The original E1 stabilizer for Ektachrome was a packet of paraformaldehyde and a bottle of liquid containing Photo Flo.

Mixing the two in hot water caused depolymerization of the paraformaldehyde. It is also know in the literature as trioxymethylene and polyoxymethylene.

The solid is a relatively safe way to store formalin. I then place it in hot water to regenerate the formaldehyde. I keep a large bottle of Fischer Trioxymethylene on my darkroom shelf. It has served me for over 30 years.

IMHO, your formalin is not bad, it just needs a thorough mix and then gentle heat.

PE
 
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RobertP

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Kerik, That may be a good idea. I went and dug out the box and paper work to make sure I didn't miss anything. The formaldehyde was shipped without a hazardous materials shipping paper. It was shipped UPS ground and the only other identifying label is a small blue sticker that says "consumer commodity ORM-D"
 
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Robert,

Unless there is a lot of sediment, the reduction in solution percentage is probably of no importance for hardening gelatin. Rather than fight with the supplier, I would try it, and if it works fine, then don't bother.

There's too many things in the world to get worked up over, and this one doesn't sound like a problem worthy of the hassle.


---Michael
 

Gerald Koch

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They also didn't ship it Hazmat like they should.
Whether something must have hazmat shipment depends on the substance and the amount. For example, one pound of sodium hydroxide (lye) does not required a permit while two pounds does. However, you can order as many pounds as you wish provided each pound is in its own package.
 
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RobertP

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Michael, You are probably right. It is not worth the hassle although I would like my money back. There is about an 1 1/2" of sediment in the bottom of a 1 liter bottle. Is this a lot? I don't know. I have nothing to compare it to because I've never seen this before and all the formaldehyde I have seen has been water clear. It is nice to get a lesson in polymerization but not at 60.00 a lesson. With that much sediment I'll just have my pharmacist order me some. I'll feel more comfortable using formaldehyde that I know is good. No sense in introducing any future problems into the process by using a chemical I'm not sure about. So I'll just chalk it up to experience. PE, I'm sure what you're saying is true. But I'm using such small amounts that a liter will last a very very long time. If I was using larger quanities then I may consider trying mixing and reheating. But even though I have a pretty good ventilated darkroom I wouldn't feel comfortable reheating formaldehyde with the family upstairs. The risk outweighs the costs. Thanks guys, Robert
 
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Robert,

Oh man, that does sound like an awful lot to me. At $60 a pop, it is a harsh lesson. If you paid with credit card, you could tell them you will dispute the charge if they don't refund your money since they sent defective product.

I'll send you a PM with some info I found on formalin...


--Michael
 

Jeremy

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I'll send you a PM with some info I found on formalin...

Michael, can you post it here? I plan on using glyoxal for hardening because I print my first coat in a day or 2, but I will be using formalin when I don't have that luxery.
 

Photo Engineer

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I use glyoxal. It works very well and does not evaporate a lot into the air so you can work with it without having a lot of heavy fumes in the lab.

PE
 
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I'll never use glyoxol again. Works fine if it is very fresh, but as the bottle ages, it causes the gelatin to yellow unacceptably, regardless of the time delay between sizing and printing the first layer.

Jeremy, unless you can't adequately handle it, I would dispense with the glyoxol and go straight to the formalin. There are some sources out there for it, but I am not going to publicly point people to them as it is a chemical used in the grug trade (at least I've been told) and is a SOB to boot, so I don't want people to casually get their hands on it.


---Michael
 

Photo Engineer

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I refrigerate my glyoxal. And, I make sure it is fresh.

I have never had a problem. Also, I don't get involved in GRUGS. LoL.

PE
 

donbga

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A 2.5% solution of gluteralhyde works great, never yellows, and leaves the paper smooth as a babies butt.
 

donbga

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And, it smells up the DR as bad or worse than formalin. There is a law suit in Australia over glutaraldehyde.

PE
That's not been my experience with it. I use very small amounts and keep containes closed.
 
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