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How to lower desired specific gravity by adding water?

I have a 12000 kg liquid of napthelene sulphonate condensate of 1.258 gravity. And I have to bring the specific gravity to 1.228 by adding tap water. What calculation I have to do? (solution is at 30 deg.temperature.)

Bhupesh Mulik
employee - Mumbai, India
June 10, 2011

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June 10, 2011

Hi, Bhupesh.

You have 12,000 kg of napthalene sulphonate, which weighs 1.258 kg per liter, so you must have 9,538 liters of it (because 12,000/1.258 = 9538).

The specific gravity of water at 30° C is about 0.996.

You are going to add X liters of water at .996 kg per liter to your 12,000 kg of napthalene sulphonate and end up with (9,538 + X) liters at 1.228 kg per liter.

So 0.996X + 12,000 = (9,538+X) * 1.228

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

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Ted, you've hereby been drafted to help my daughter with her math homework next year!

Marc Green
anodizer - Boise, Idaho
June 16, 2011

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I am working as lab chemist and want to know exact volumetric procedure or any other process for determination of napthelene sulphonate formaldehyde condensate (liquid and powder form)? Our product is used in making admixture for concrete. Now we did only pH, viscosity and specific gravity test, moisture test only. I want to know chloride test, sulphated ash test, mineral test, mini slump test, mineral test, bulk density test or any other test which is accepted worldwide and ASTM for napthelene sulphonate formaldehyde condensate also.
I hope I will get good respnse as soon as possible.

Bhupesh Mulik
employee - Mumbai, India
June 19, 2011

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I have a one litre of napthelene sulphonate condensate liquid of 1.258 gravity at 30c temp.I want to lower sp.gravity upto 1.228 at 30c temp by adding water.what calculation I have to do? is it depends on solid present in napthelene sulphonate condensate?
how should I reduced the 1.258 sp.gravity at 45c temp to 1.228 at 30c temp?

Bhupesh Mulik
employee - Mumbai, India
July 5, 2011

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Hi, Bhupesh.

This question was asked, answered, followed up, and clarified. Please explain what the difficulty is, rather than just starting over again. Thanks!

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
July 5, 2011

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July 11, 2011

I have to adjust my company's storage tank to 1.228 or 1.216 sp.gravity at 30° c temp.
storage tank temp.is always above 50° c temp.so its very difficult to adjust required gravity for 30° c temp.sometime it shows lower & sometime it shows higher than expected gravity.so it takes lots of time to circulate whole tank to mix water, sometimes a pH problem is also created.
1)at 30° c temp ,how much water I have to add in one lit solution of 1.258 gravity to bring it 1.228 at 30° c temp (same temp) ?
2)at 52° c temp,how much water I have to add in one lit solution of 1.258 gravity to bring it 1.228 at 30° c temp?

Bhupesh Mulik
- Mumbai, India

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July 12, 2011

Hi All

I must say that I am impressed by the calculations that should get you close but my poor old memory nags me that Specific gravity is a non-colligative property so it may not be that simple!

The foolproof way is surely to take a litre and "titrate" with water to a SG "endpoint".

I am still a little worried about measuring SG to three decimal places. This calls for some pretty accurate calibration and at 30C, evaporation starts to be a consideration and at 52C makes measurement very difficult.

So I must question the need for this accuracy. Why not talk to your customer about what they actually want to achieve? They may actually like it a little more concentrated!

Geoff Smith
Hampshire, England

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Titrating a sample and scaling it up does sound like a very good and practical solution, Geoff. Thanks.

I'm confident that both the volumes and the masses of the two liquids are additive; in which case density/specific gravity can be reliably calculated based on the volumes and masses of the constituents (although I won't challenge your points about evaporation, measurement, and 3 decimal point accuracy).

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
July 12, 2011

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August 7, 2011

hi,
we manufacture napthelene sulphonate formaldehyde condensate in liquid form, our product has different specific gravity such as 1.258,1.228,1.218 at 30° C. when I dried this 3 to 4 gm of liquid solution in petri dish at 110 ° C for 1.5 hrs, and then I weigh those dried solids, I got different weights which are in decreasing order with resp. to specific gravity of our product.
So is there any calculation for measuring dried solids contained in a liquid which are dependent on specific gravity?

Bhupesh Mulik
employee - Mumbai, India