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How To Measure Acidity Of activated Fullers Earth
DATE: 2013/12/10


How To Measure Acidity Of Activated Bleaching Earth

Acidity in activated bleaching earth is sulfuric acid that is still inside the powder.After activating process of fuller's earth,it is washed with water to clean it from sulfuric acid;but there is still a little amount sulfuric acid remaining in the activated fullers earth.

Acid sulfate in activated bleaching earth that is allowed for human safety and oil refinery equipment safety also is maximum =3.9mg KOH/gram.

How to measure acidity in activated fullers earth:


1.Making pp indicator solution :

Dissolved 2 grams Phenolpthalein into liquid alcohol 70% as much as 100 ml.

2.Making KOH solution(0.1Normal)

Dissolved 5.61 grams of pure KOH with aquadest into 1000ml.

3.Making activated fullers earth solvent that is wanted to measure:

Dissolved 5 grams of activated bleaching earth with aquadest 100 ml.

Heat the solvent at a temperature of 30-40 degrees Celsius for 5 minutes.

Filter the solvent with filter paper and take only 25 ml.

Measuring process:

1.Fill buret tube with KOH solution(0.1Normal) into zero point.

2.Drops PP indicator solution as much as 2 drops into the 25 ml of activated bleaching earth solvent and stir it for a while until they mixed up.

3.Put the activated fullers earth solvent under the buret tube.Open the buret tube tap a little, so the buret content drops slowly.ShAKE the glass of activated fullers earth solvent until the color change to pink.

4.Color of activated bleaching earth solution will be still pink,although we shake the glass for a then close the buret tap.

5.See at the buret tube how much(ml) of solution that has been drops into the activated fullers earth solvent.The result is called VP ml.

6.With this formula we got the acidity of activated fullers earth result:(VP X 0.1×56.1×4) / 5 =... mg KOH /gram