Sciencemadness Discussion Board

Aluminium Triacetate

Waffles SS - 6-2-2012 at 22:21
Quote:

The triacetate forms when aluminium sulfate is mixed with barium acetate
http://en.wikipedia.org/wiki/Aluminium_acetate


I want to use calcium acetate instead of barium acetate(due to Toxicity of barium acetate,i want to use it in medicine cream)
First i want to find out exactly how many water molecular my aluminium sulfate has?
I did some experience for this purpose but i was unsuccessful.
First i did below reaction:

Al2(SO4)3 + 6 NaHCO3 → 3 Na2SO4 + 2 Al(OH)3 + 6 CO2

I used 100gram Aluminium sulfate and got only 25 gram Aluminium hydroxide!(my aluminium sulfate is big shiny crystall and at last it should be 17-18 hydrate but i got amazing result)
also i did below reaction:

Al2(SO4)3 + 6 NaOH = 2 Al(OH)3 + 3 Na2SO4

I got another amazong result.this reaction happen only in 90-100 c and doesnt happen at room temperature and i think it must react rapidly!
finally i decide to dry my aluminium sulfate by heat but i read some where that it will decompose on 90c!
Now i really have no idea for finding a way to determine water molecule in my aluminium sulfate
Also i didnt find any information about Aluminium triactate?like solubility in water?melting point?..



LanthanumK - 7-2-2012 at 06:31

First, a slight excess of aluminium sulfate will precipitate all of the barium as the harmless barium sulfate. Barium sulfate can be consumed in large quantities without adverse effects.

Aluminium hydroxide dissolves easily in an excess of sodium hydroxide to form sodium aluminate, which is soluble in water.

The decomposition of aluminium sulfate at 90 degrees constitutes the loss of the water molecules. Anhydrous aluminium sulfate melts at 770 degrees Celsius.

I once dissolved freshly precipitated aluminium hydroxide in acetic acid. When evaporated, wet crystals smelling strongly of acetic acid are formed. They are readily soluble in water and are likely hygroscopic. I would assume that they decompose when heated to acetic acid and aluminium hydroxide.

Aluminium acetate.JPG - 138kB

blogfast25 - 7-2-2012 at 06:42

Correct, Lanthanum K, Waffles added too much strong alkali and obtained <i>aluminate</i> (Al(OH)<sub>4</sub><sup>-</sup>;), which then hydrolysed to hydrated alumina on heating.

To avoid this problem, precipitate the aluminium using ammonia solution, which isn't alkaline enough to redissolve the alumina to aluminate...

Waffles SS - 7-2-2012 at 10:20

Quote: Originally posted by LanthanumK  
First, a slight excess of aluminium sulfate will precipitate all of the barium as the harmless barium sulfate. Barium sulfate can be consumed in large quantities without adverse effects.

Aluminium hydroxide dissolves easily in an excess of sodium hydroxide to form sodium aluminate, which is soluble in water.

The decomposition of aluminium sulfate at 90 degrees constitutes the loss of the water molecules. Anhydrous aluminium sulfate melts at 770 degrees Celsius.

I once dissolved freshly precipitated aluminium hydroxide in acetic acid. When evaporated, wet crystals smelling strongly of acetic acid are formed. They are readily soluble in water and are likely hygroscopic. I would assume that they decompose when heated to acetic acid and aluminium hydroxide.


Thanks my friend,
I think combination of aluminium hydroxide with acetic acid make aluminium diacetate not Triacetate.you think your aluminium acetate decomposed during evaporation step?
Do you have any information about aluminium triacetate?
I didnt make strong alkaline solution(i made 1 molar NaOH solution)also i add 50% aluminium sulfate solution to NaOH solution .
I think sodium aluminate produce only in strong alkaline solution not in my experience

AJKOER - 8-2-2012 at 13:50

Per one of my references, Aluminum triacetate can be produced by dissolving Aluminum sulfate in Lead or Barium acetate solution.

Same source, Aluminium diacetate from Sodium aluminate and acetic acid.

[Edited on 9-2-2012 by AJKOER]

blogfast25 - 9-2-2012 at 09:48

Aluminium is probably quite soluble in 20 - 30 % acetic acid, applying mild heat.

Nicodem - 9-2-2012 at 14:37

I will be surprised if someone finds a veritable source that confirms that something like aluminium triacetate can be prepared by aqueous chemistry. Aluminium triacetate, if it exists at all, should be more acidic than acetic acid, so it seems totally counterintuitive that it could be formed from acetic acid or acetates in water and furthermore be stable toward hydrolysis!
Quote: Originally posted by AJKOER  
Per one of my references, Aluminum triacetate can be produced by dissolving Aluminum sulfate in Lead or Barium acetate solution.

Same source, Aluminium diacetate from Sodium aluminate and acetic acid.

Is one of your references, that for some reason you don't cite, perhaps the referenceless wikipedia page http://en.wikipedia.org/wiki/Aluminium_acetate ?

Edit: Again someone started a thread without doing the homework. Five seconds of UTFSE gives the previous thread on the topic:
Quote: Originally posted by bbartlog  
The downside of this is that the triacetate of aluminum is not easily made. The preparation in Brauer *starts* with acetic anhydride. Similarly there is a US patent (2141477) which, while using far smaller quantities, still starts with acetic anhydride to prepare neutral aluminum acetate. Wikipedia suggests barium acetate plus aluminum sulfate, but I can't find whatever primary reference this is based on (if indeed it isn't just pure fabrication).


[Edited on 9/2/2012 by Nicodem]

AJKOER - 9-2-2012 at 17:49

My source on the preparations is "Concise Encyclopedia Chemistry", by Walter de Gruyter, on the topic of Aluminum Acetates, page 51. Now, in defense of my source, in its cited preparation of HIO3 (I2 + H2O + Cl2), it does mention the need for Ag2O to remove the created HCl for the reaction to be successful, unlike Wikipedia.

De Gruyter's book per its name, however, is concise in its preparation details, but, to date, I believe it to be mostly accurate. My recommendation is to consult a more extensive source if more detail is suspected to be necessary for a successful synthesis.

FYI, I have now searched Wikipedia and found precisely the same double recipe quoted in De Gruyter's book. However, I believe the unspoken detail is the slow nature of the reaction. See "Pharmaceutical and pharmacological evaluation of Burow's solution (aluminum acetate solution), hospital preparation, and development of its rapid preparation method]" by Ishibashi Y, Murakami T, Yumoto R, Sakai M, Shintani H, Itaha H, Kanbe M, Masuda S, Yajin K, Kihira K, Takano M.

Abstract
Burow's solution, or aluminum acetate solution, is effective in inhibiting various microorganisms including methicillin-resistant Staphylococcus aureus (MRSA) that are commonly observed in chronic suppurative otitis media. It takes several days to prepare Burow's solution using aluminum sulfate, and the pharmaceutical properties of the solution are not fully understood. In this study, the effect of storage (5 months) of Burow's solution prepared according to the Teine-Keijin Hospital manual on its pharmaceutical properties and antibacterial activities was examined. We also attempted to develop a rapid preparation method of aluminum acetate (or 1.7% aluminum) solution using two commercially available compounds of aluminum acetate basic (Al(2)O(CH(3)CO(2))(4), Al(OH)(CH(3)CO(2))(2)). The properties of Burow's solution, pH, osmolarity and antibacterial activity, were the same among different preparations and its storage for 5 months at 4 degrees C had no effect on these properties. The antibacterial potency of Burow's solution was dependent on aluminum concentration and its antibacterial potency against S. aureus and several MRSA strains was of the same magnitude. In a rapid preparation, aluminum acetate basic was mixed with appropriate amounts of tartaric acid and acetic acid, and the suspension was boiled for 2-2.5 hr until dissolved. The rapidly prepared aluminum acetate solution showed the same pharmaceutical properties and antibacterial activities as those of Burow's solution. The newly developed preparation method for aluminum acetate solution is expected to be convenient and feasible for hospital treatment of chronic suppurative otitis media."

There is also a patent to speed up the reaction and make more stable solutions:
"Method of preparing stable aluminum acetate solutions"
Patent 5233065 Issued on August 3, 1993.

"In Applicant's process, 0.1-1.0 mols of acetic acid is added to 1 mol of the basic aluminum halide with adequate mixing. Best results and process feasibility are obtained when the basic aluminum halide solutions are adequately mixed during the addition of the glacial acetic acid. The addition of the glacial acetic acid causes the formation of white precipitate which is believed to be basic aluminum acetate. The precipitate redissolves soon after its formation. After all the glacial acetic acid has been added, the batch is then mixed for a period of time until a clear solution is obtained (usually 30 minutes, and in some cases with very large batches one hour). Next, while still mixing add alpha hydroxy carboxylic acid salt having a neutral to mildly alkaline (7-10) pH is added in concentrations of 2-20% by weight of alpha hydroxy carboxylic acid salt in the final solution, such as sodium, ammonium, potassium, or triethanolamine lactates, citrates or tartrates, or mixtures thereof, is added and mixing of the solution continues until a uniform clear solution is obtained. The final solution contains aluminum as aluminum trioxide in concentrations of 1-22% by weight with a preferred range of 10-20% by weight"







[Edited on 10-2-2012 by AJKOER]

Waffles SS - 9-2-2012 at 21:28

Quote: Originally posted by Nicodem  
I will be surprised if someone finds a veritable source that confirms that something like aluminium triacetate can be prepared by aqueous chemistry. Aluminium triacetate, if it exists at all, should be more acidic than acetic acid, so it seems totally counterintuitive that it could be formed from acetic acid or acetates in water and furthermore be stable toward hydrolysis!
Quote: Originally posted by AJKOER  
Per one of my references, Aluminum triacetate can be produced by dissolving Aluminum sulfate in Lead or Barium acetate solution.

Same source, Aluminium diacetate from Sodium aluminate and acetic acid.

Is one of your references, that for some reason you don't cite, perhaps the referenceless wikipedia page http://en.wikipedia.org/wiki/Aluminium_acetate ?

Edit: Again someone started a thread without doing the homework. Five seconds of UTFSE gives the previous thread on the topic:
Quote: Originally posted by bbartlog  
The downside of this is that the triacetate of aluminum is not easily made. The preparation in Brauer *starts* with acetic anhydride. Similarly there is a US patent (2141477) which, while using far smaller quantities, still starts with acetic anhydride to prepare neutral aluminum acetate. Wikipedia suggests barium acetate plus aluminum sulfate, but I can't find whatever primary reference this is based on (if indeed it isn't just pure fabrication).



This is not my homework(which university or high school has this home work?)I Graduate 3 years ago.
One of my friend requested this to me and i like to make it(he is Pharmacist)

You want to say Barium Acetate + aluminium sulfate goes different route?
I tested it one time and i am sure i got barium sulfate(when i mix these together lot of Sediment appeared.sure that is barium sulfate)
Unfortunately i didnt have enough time for evaporating solution and testing soluble material

AJKOER - 10-2-2012 at 07:16

A obvious point, but given that the solution is intended for medical use and assuming you use a Barium salt path, please employ an excess of Aluminium sulfate and allow sufficient time to convert all the Barium acetate, as it is a toxic salt.

bbartlog - 10-2-2012 at 08:31

Quote: Originally posted by AJKOER  
Burow's solution, or aluminum acetate solution,


OK, but this is not the same thing as preparing aluminium triacetate. Taking basic aluminium acetate and adding acetic acid in solution may indeed get you a solution that has three times as much acetate as aluminium, ion for ion... and if you then try to isolate the compound mentioned in the thread title you'll end up with that same basic aluminium acetate along with acetic acid. It is more or less the same problem as trying to prepare anhydrous AlCl3 via aqueous solution, i.e. essentially impossible.

AJKOER - 10-2-2012 at 14:38

Per Waffes SS: "One of my friend requested this to me and i like to make it (he is Pharmacist)"

In my opinion, the answer to the Pharmacist's questions relates to one or both of the following :

Source: "The Free Dictionary" by Farlex:

"Aluminum acetate topical solution": a preparation of aluminum subacetate solution, glacial acetic acid, and water; an astringent applied topically to the skin as a wet dressing and used as a gargle or mouthwash.

"Aluminum subacetate topical solution": a solution of aluminum sulfate, acetic acid, precipitated calcium carbonate, and water; applied topically as an astringent, and also as an antiseptic and a wet dressing.

"Burow's solution": a liquid preparation containing aluminum sulfate, acetic acid, precipitated calcium carbonate, and water, used as a topical astringent, antiseptic, and antipyretic for a wide variety of skin disorders. Also called aluminum acetate solution.
(from Mosby's Medical Dictionary, 8th edition. © 2009, Elsevier) . LINK: http://medical-dictionary.thefreedictionary.com/Burow's+solution

Now, based on these definitions, Burow's solution is another name for Aluminum subacetate topical solution.

However, "Aluminum subacetate Topical Solution" is, per another reference, described as:

"Aluminum Subacetate Topical Solution

C4H7AlO5 162.08

Aluminum,bis(acetato-O)hydroxy-.
Bis(acetato)hydroxyaluminum.
Basic aluminum acetate [142-03-0;8000-61-1].
Aluminum Subacetate Topical Solution yields, from each 100mL, not less than 2.30g and not more than 2.60g of aluminum oxide (Al2O3), and not less than 5.43g and not more than 6.13g of acetic acid (C2H4O2). It may be stabilized by the addition of not more than 0.9percent of boric acid.
Aluminum Subacetate Topical Solution may be prepared as follows.

Aluminum Sulfate 145g
Acetic Acid 160mL
Calcium Carbonate 70g
Purified Water,a sufficient quantity,
to make 1000mL

Dissolve the Aluminum Sulfate in 600mLof cold water, filter the solution,and add the Calcium Carbonate gradually, in several portions,with constant stirring.Then slowly add the Acetic Acid,mix,and set the mixture aside for 24hours. Filter the product with the aid of vacuum if necessary, returning the first portion of the filtrate to the funnel. Wash the magma on the filter with small portions of cold water,until the total filtrate measures 1000mL."

LINK: http://www.newdruginfo.com/pharmacopeia/usp28/v28230/usp28nf...

I describe the expected reaction above as the formation of Calcium acetate and CO2 (Acetic acid + CaCO3), and a double replacement reaction with Aluminum sulfate forming insoluble CaSO4 and the basic Aluminium diacetate.

Note also, per Wikipedia, the stated formula above for this topical preparation is for basic Aluminium diacetate, HOAl(C2H3O2)2. The diacetate, per Wikipedia, can also be prepared in a reaction between sodium aluminate (NaAlO2) and acetic acid.

Now, if the Pharmacist is instead interested in ""Aluminum acetate topical solution", then the preparation suggests per Wiki, "bringing together aluminium hydroxide, acetic anhydride and glacial acetic acid in water, forming the basic aluminium monoacetate".

Hence, this thread, in my humble opinion, should be about the basic Aluminum acetates and not Aluminum triactetate as these are the topical solutions of interest to a Pharmacist.







[Edited on 10-2-2012 by AJKOER]

Waffles SS - 10-2-2012 at 22:20

Thanks AJKOER ,You are right.
My friend just told me aluminium acetate(not aluminium triacetate)
I searched in google and foundout reaction between aluminium sulfate and calcium acetate use in medicine also i foundout (in wiki) that aluminium triacetate prepare by this reaction.I thought that aluminium triacetate produce by this method but now i findout basic alumium acetate is final product

Basic alumium acetate is insoluble in water but sodium aluminate is soluble,i think its better to prepare Basic aluminium acetate by sodium aluminate + acetic acid
NaAlO2 +3AcOH = Al(AcO)2OH + AcONa + H2O


[Edited on 11-2-2012 by Waffles SS]

Nicodem - 11-2-2012 at 13:06

Quote: Originally posted by Waffles SS  
I Graduate 3 years ago.

Not from chemical sciences, I guess.
Quote:
One of my friend requested this to me and i like to make it(he is Pharmacist)

It causes shivers in my spine to realize we have members who are so unscrupulous to potentially poison people with barium and who knows what. Did it not occur to you that, if a pharmacist asked you to prepare something, it was because it was intended for use on humans? Pharmacists have pharmacopeias and pharmaceutical specifications exactly for such reasons! Instead, you don't even know which pharmaceutical preparation you are supposed to prepare.
Quote:
You want to say Barium Acetate + aluminium sulfate goes different route?

If you would have taken five minutes to read thread I linked to, you would have realized by now that aqueous solutions of aluminium triacetate don't exist. It is simply thermodynamically improbable that such a compound could exist in aqueous solution. That's what you get by believing some bogus unreferenced wikipedia claims.
Quote:
Basic alumium acetate is insoluble in water but sodium aluminate is soluble,i think its better to prepare Basic aluminium acetate by sodium aluminate + acetic acid
NaAlO2 +3AcOH = Al(AcO)2OH + AcONa + H2O

If you can't get more responsible and give up with this nonsense, at least be decent enough to use the procedure from your local pharmacopoeia before you cause someone to get hurt!

AJKOER - 11-2-2012 at 16:14

Waffles SS:

Thanks for honesty.

You would be surprised how rarely anyone actually admits to a mistake on this forum.

I am glad that my deductions may have aided you and your friend from much more than an mere embarrassment.

Waffles SS - 11-2-2012 at 22:09

Quote: Originally posted by Nicodem  

Not from chemical sciences, I guess.

Organic chemistry & Computer (Software)
I am student of chemistry for ever
Quote: Originally posted by Nicodem  

It causes shivers in my spine to realize we have members who are so unscrupulous to potentially poison people with barium and who knows what. Did it not occur to you that, if a pharmacist asked you to prepare something, it was because it was intended for use on humans? Pharmacists have pharmacopeias and pharmaceutical specifications exactly for such reasons! Instead, you don't even know which pharmaceutical preparation you are supposed to prepare.

I dont know who is Pharmacists in your country but in my country Pharmacists should make:Aspirine,Paracetamole,Peniciline,.. and test these drugs in him/her body
Also i think searching in internet and in book library is first step for making chemicals reagent(like drug) now i am at this level
Quote: Originally posted by Nicodem  

If you would have taken five minutes to read thread I linked to, you would have realized by now that aqueous solutions of aluminium triacetate don't exist. It is simply thermodynamically improbable that such a compound could exist in aqueous solution. That's what you get by believing some bogus unreferenced wikipedia claims.


Where i said i want aluminium triacetate solution?(name of this topic is aluminium triacetate not solution of aluminium triacetate!)
Also i found interesting method for making Aluminium triacetate:
aluminium triacetateAl(O2CMe)3,can be prepared by heating AlCl3 or al powder with a mixture of acetic acid and acetic anhydrid
Chemistry of aluminium, gallium, indium, and thallium

By Anthony John Downs
http://books.google.com/books?id=v-04Kn758yIC&pg=PA158&a...
Quote: Originally posted by Nicodem  

If you can't get more responsible and give up with this nonsense, at least be decent enough to use the procedure from your local pharmacopoeia before you cause someone to get hurt!

Dont worry my friend
He want analysis paper too and they are not hurtable
Thanks Ajoker ;)





[Edited on 12-2-2012 by Waffles SS]

Waffles SS - 20-2-2012 at 10:13

Today i tried to make Basic Aluminium Acetate and i got amazing result

First i dissolved 2 kilogram of Sodium Aluminate hydrate in 4lit of water then i added 3600 gram of acetic acid in three portion.after adding first portion the temp increased and all of my solution suddenly get solid and all of water disappeared after adding second portion all of solid dissolved and solution got milky and finally after adding third portion i tried to filter solution but i was unsuccessful and even with vacuum i couldnt to filter solution(water didnt pass from filter paper.i had to use cloth for filter step)

But amazing step is final product.after drying i just got 500gram white powder.really this is Basic aluminium acetate?

blogfast25 - 21-2-2012 at 10:54

Did you check stoichiometry?

During the first addition you're neutralising the aluminate and Al(OH)3 drops out. On further addition this will redissolve to Al acetate but you get a mixture of Al acetate and Na acetate.

Waffles SS - 21-2-2012 at 11:13

Yes i checked Stoichiometry,

NaAlO2*H2O + 3AcOH = AcONa + Al(AcO)2OH*H2O + H2O

~100gram + 180 = 82 + 180

x20=

2000 +3600 = 1640 + 3600

Also i confused when i added aluminium hydroxide to acetic acid,aluminium hydroxide didnt dissolved in acetic acid !!!
I warmed solution but it seems aluminium hydroxide didnt react with acetic acid
If really Basic aluminium acetate is insoluble in water we can make it from Sodium acetate + aluminium Sulfate and also another possible method.(merck wrote this is insoluble in water)
I really dont know i made Aluminium diacetate or Aluminium monoacetate!(i am really confused)



[Edited on 21-2-2012 by Waffles SS]

blogfast25 - 21-2-2012 at 14:27

We have to assume it is insoluble, otherwise a prescribed synth. from Na aluminate and acetic acid makes NO sense (as it would be impossible to separate the two acetates).

Really you need to determine the Al content of the final product after washing and drying. Digest a weighed sample in conc. H2SO4 and determine Al volumetrically with EDTA titration? If Al content of the dry product corresponds to stoichiometry of basic aluminium acetate, you can be sure the product is basic aluminium acetate.

High(ish) temperature digestion of the dry product with conc. H2SO4 may also allow to determine acetate content (collect the displaced HAc and acid-base titrate it).





[Edited on 21-2-2012 by blogfast25]