aluminum sulfate question

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Facundo V
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aluminum sulfate question

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I need to know, how to dilute aluminum sulfate in grains to liquid, and correction of pH and amber color for drinking water.
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ChenBeier
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Re: aluminum sulfate question

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Aluminiumsulfate is a white power and should be dissolved in water without any colour. Depending of the pH aluminiumhydroxide can precipitate. Addition of some sulfurc acid helps. Where does the ambor colour comes from.
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Re: aluminum sulfate question

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I need to make a solution of Aluminum Sulfate with 8% of total useful Oxides being

TOTAL USEFUL OXIDE = Al2 03 + 0.638 Fe2 03 Expressed as Al2 03


I have aluminum sulfate in flakes, which according to the supplier's file contains the following ...

Total Useful Oxides (OUT)% 17.2
Aluminum Oxide (AI2 O3)% 17.2
Insoluble residue% 0.16
Ferrous Oxide (FeO)% 0.001
Manganese (Mn)% n / c
Free alkalinity% 0.08
Free acidity% n / a
Ferric Oxide (Fe2O3)% 0.01
Facundo V
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Re: aluminum sulfate question

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I want to know what it means... Al2 03 + 0.638 Fe2 0 ??? Aluminum sulfate + added 0.638 of Ferric Oxide? ... is this why the Amber color may be due?
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ChenBeier
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Re: aluminum sulfate question

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I think you have raw product, which contains also iron, thats why the solution gets amber colour.

1 g Al2O3 is equal to 3.35 g Al2(SO4)3 = 6,53 g Al2(SO4)3 × 18 H2O

Its not clear what useful oxids mean. If it contain only 17% Al2O3, what is the 83% ? Sulfur and oxygen, water, iron, anything else?
If you have 100% Al2(SO4)3 then it contains 29,8% Al2O3, in case of the hydrated salt it is only 15,3 %. What is close to your number 17%.

So you have to make a solution lets say 1 kg made of 522 g hydrated salt and 477,12 g water.

Or 1kg made of 268,45 g anhydrated salt and 731,54 g water.

With your product it will be 470,6 g salt and 529,4 g water.

For calculation of volume you need specific gravity of the solution.
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Re: aluminum sulfate question

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Thank you very much, what if I would like to communicate in some other way if possible, so that the conversation is more direct and to be able to explain myself better, since you know a lot, I know that it is a forum but it is an interesting topic and if you can teach I would be very grateful as a human being. Good day
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Re: aluminum sulfate question

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I can teach here. Other people also can watch and participate in the conversation.
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Re: aluminum sulfate question

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Perfect, the issue is like this, I have to prepare a solution of Aluminum Sulfate in water and they ask me the following:

TOTAL USEFUL OXIDES: Expressed as Al2O3: it must contain 8% as a base, and with a minimum tolerance of 7.5% of useful oxides, understood as the sum of oxide of aluminum and ferric oxide (expressed in its equivalent as aluminum oxide) contained in the product.

TOTAL USEFUL OXIDES = Al2 03 + 0.638 Fe2 03 Expressed as Al2 03



What is meant by that? and how would you prepare it? I have dry base aluminum sulfate that according to the product's technical sheet has 17.02% of Al2O3 ... :?:
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Re: aluminum sulfate question

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then they ask me ..

FERROUS OXID: Expressed as FeO: It should not contain ferrous oxide (Feo) in an amount greater than 0.1% of the useful oxides. Maximum without tolerance.

MANGANESE: Expressed as Mn: It should not contain manganese Mn) in an amount greater than 0.3% of the useful oxides. Maximum without tolerance.


INSOLUBLE WASTE: It must not contain insoluble residue in an amount greater than 1.3%
the weight of the product. Maximum without tolerance.

ARSENIC: Expressed as (As): It must not contain arsenic in an amount greater than 0.05
% of useful oxides. Maximum without tolerance.

FREE ACIDITY: Expressed as (S04H2). It must not contain free acidity in an amount greater than 0.5% of the weight of the product. Maximum without tolerance.

DETERGENTS and INTERFERENCES: It should not contain detergents and interferences in
a concentration greater than 0.007% of the useful oxides. Maximum without tolerance
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Re: aluminum sulfate question

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How do I make a solution that meets all these requirements? .. I know that there are two types of aluminum sulfate, type A and B

Aluminum sulfate is a salt with the formula Al2 (SO4) 3, it is solid and white (in the case of type A aluminum sulfate, with an iron content of less than 0.5%) and brown in the case of type B aluminum sulfate. (iron content less than 1.5%).


I think that the amber color that I have in a sample is due to iron oxidation, which I don't know, is if you have to add iron or does that come all in the same raw material and is it just diluting it?
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Re: aluminum sulfate question

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TOTAL USEFUL OXIDES = Al2 03 + 0.638 Fe2 03 Expressed as Al2 03

With the given salt it is not possible to get the high iron concentration, because it contain only 0.01 Fe2O3.
What I understood is to make a 1.638 mol solution of Al2O3 used as Al2( SO4)3 equal 560,42 g. This correspond to 167,01 g Al2O3
Divide bei 2 will get 83,5 g. So if you dissolve 280,21 g of the sulfate to make 1 kg solution you get 8.3%. All other numbers are driven of the purity of the given rsw product.
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Re: aluminum sulfate question

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perfect, you say then that by diluting 280.21g in 719.79g of water, I get an 8% solution?
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Re: aluminum sulfate question

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It gives me an acid product, that solution can be added something to raise the pH? ...


something is missing, because if the iron gives the color amber, then I would have to add iron, right? If so, how would the process be?
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Re: aluminum sulfate question

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Aluminiumsulfate is acidic from nature. Which pH you need? Be aware if you add sodiumhydroxide you would get precipitation of aluminiumhydroxide. The technical aluminiumsulfate contain as impurities iron compounds. Why you will add additional iron? If you need iron additionally then you have to add ironsulfate.
By the way , what is the purpose of this solution?
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Re: aluminum sulfate question

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We are a group of students from Argentina and we are behind this project for drinking water flocculation.

It is a pleasure to be able to speak with you, thank you.
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