what is difference between acetone and dry acetone?
- Thread starter ifeelsorry
- Start date
It's all about water content. Dry is a colloquial term meaning anhydrous = containing no water. You want your acetone to be as pure as possible with as little water content as possible. Don't blindly purchase that "dry acetone". Instead, check the detailed specs or safety sheets and get the finest acetone you can find that you can afford. For the purposes of making 4-MMC acetone >99.5 % is completely fine and does not break the bank.
Generally any Acetone which comes in a metal can is anhydrous enough for your purposes.
As those cans rust like mad in the presence of water and for this reason only solvents which are essentially free of water are sold in tin cans.
This is more reliable then what a seller claims. I not so long ago bought some IPA off Amazon which was labeled and sold as 99.98% IPA. Came out it was not only not dry but more like 30% water, and there were even more adulterants present. It was very cheap. Well it would have been cheap if it had not been useless. So sellers can and do mislabel solvents, but they cannot cheat a can - this rusts with water and thats it.
As those cans rust like mad in the presence of water and for this reason only solvents which are essentially free of water are sold in tin cans.
This is more reliable then what a seller claims. I not so long ago bought some IPA off Amazon which was labeled and sold as 99.98% IPA. Came out it was not only not dry but more like 30% water, and there were even more adulterants present. It was very cheap. Well it would have been cheap if it had not been useless. So sellers can and do mislabel solvents, but they cannot cheat a can - this rusts with water and thats it.
It would be better even to distill any acetone (even dry) before synthesis over P2O5 B2O3 or CaCl2 to remove any water and impurities.
Drying of Acetone. Acetone has been dried with a wide
spectrum of desiccants.8 Thus, alumina, calcium chloride,
phosphorus pentoxide, and 4A molecular sieves,16 as well as
calcium and (anhydrous) cupric sulfate, have all been used.
Since acetone has the lowest dielectric constant of the sol-
vents investigated here, it might be predicted that its drying
should be relatively easy. In fact, in many respects the drying
of acetone proved to be the most difficult case. As with Me2SO,
the root of the difficulty is the acidic a protons, which in this
case compounds the drying problem not only by inflating
apparent water content by exchange process but also by
providing a pathway to self-condensation through enol in-
termediates. This facet of acetone chemistry makes the choice
of a successful desiccant a delicate process. As Table IV shows,
mild siccatives such as calcium sulfate are inept; more potent
desiccants such as molecular sieves exhibit a short initial
drying action but thereafter actually cause disastrous in-
creases in water content by displacement of the condensation
equilibrium. This interpretation was confirmed for molecular
sieves and other basic desiccants such as barium oxide by gas
chromatographic analysis which demonstrated the presence
of mesityl oxide in the dried solvent (see Table IV).
In summary, while both cupric sulfate and 3A molecular
sieves are clearly at least useful preliminary desiccants, the
agent par excellence for acetone is powdered boric anhydride.
Using stirring and sequential drying conditions, this siccation
gave a solvent containing only 18 ppm of water and caused no
detectable condensation. In fact, the true water content is
likely to be lower as even with the premise that drying occurs
considerably faster than other processes, some labeling via the
enol surely occurs on preparation of the standard wet solu-
tion.
In view of the remarkable efficiency of this desiccant for
acetone and acetonitrile,1 it is puzzling that boric anhydride
is not particularly outstanding for other members of this series
(Tables I—III). This finding emphasizes once more the danger
in assuming the existence of any kind of absolute scale in the
efficiency of desiccants for solvent drying.
Source: https://doi.org/10.1021/jo00414a038
Drying of Acetone. Acetone has been dried with a wide
spectrum of desiccants.8 Thus, alumina, calcium chloride,
phosphorus pentoxide, and 4A molecular sieves,16 as well as
calcium and (anhydrous) cupric sulfate, have all been used.
Since acetone has the lowest dielectric constant of the sol-
vents investigated here, it might be predicted that its drying
should be relatively easy. In fact, in many respects the drying
of acetone proved to be the most difficult case. As with Me2SO,
the root of the difficulty is the acidic a protons, which in this
case compounds the drying problem not only by inflating
apparent water content by exchange process but also by
providing a pathway to self-condensation through enol in-
termediates. This facet of acetone chemistry makes the choice
of a successful desiccant a delicate process. As Table IV shows,
mild siccatives such as calcium sulfate are inept; more potent
desiccants such as molecular sieves exhibit a short initial
drying action but thereafter actually cause disastrous in-
creases in water content by displacement of the condensation
equilibrium. This interpretation was confirmed for molecular
sieves and other basic desiccants such as barium oxide by gas
chromatographic analysis which demonstrated the presence
of mesityl oxide in the dried solvent (see Table IV).
In summary, while both cupric sulfate and 3A molecular
sieves are clearly at least useful preliminary desiccants, the
agent par excellence for acetone is powdered boric anhydride.
Using stirring and sequential drying conditions, this siccation
gave a solvent containing only 18 ppm of water and caused no
detectable condensation. In fact, the true water content is
likely to be lower as even with the premise that drying occurs
considerably faster than other processes, some labeling via the
enol surely occurs on preparation of the standard wet solu-
tion.
In view of the remarkable efficiency of this desiccant for
acetone and acetonitrile,1 it is puzzling that boric anhydride
is not particularly outstanding for other members of this series
(Tables I—III). This finding emphasizes once more the danger
in assuming the existence of any kind of absolute scale in the
efficiency of desiccants for solvent drying.
Source: https://doi.org/10.1021/jo00414a038
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- By Anarchy Labz
I heard that most commercial acetone is made through the cumene process which requires dry conditions and therefore you get dry acetone, if this is true why do people dry their acetone? I am not saying all acetone is dry, I am just asking where does the water come from, is it from the packaging process or something like that?
I have certainly bought solvents at the very beginning of my career that were off the shelf, in cans, only to later realize that there was water present... because the fucking caps were not airtight.. so even though great advice, it is best to just make friends with any kind of business that orders chemicals and ask if you can order some solvents for construction purposes (just an example) along with them. They could leverage the price by doing you a favor, some people definitely do agree to such propositions. If they are a legit business owner, most likely they can request paper certificates for the products, no chemical company is gonna sell hundreds dollars worth of acetone and risk it, no serious company that is. They are very aware there are companies buying with special purposes (ex. production lines) and if they misled and were found at fault, the monetary consequences could ruin them.
As for buying the IPA off Amazon.. yeah, I bought Acetone off Amazon once and it came already colored yellow with sediments, was supposed to be ACS grade, so I feel you on that. I came to the conclusion it was not the optimal place to buy my supplies.
As for buying the IPA off Amazon.. yeah, I bought Acetone off Amazon once and it came already colored yellow with sediments, was supposed to be ACS grade, so I feel you on that. I came to the conclusion it was not the optimal place to buy my supplies.