Analysis of Acid in Pickling Acid tanks using the dropper bottle method
1.0 Purpose
1.1 To provide quick, reliable in house test results.
2.0 Reagents
2.1 ACID TITRANT : Sodium Carbonate (Na2CO3) M.W. 105.99. This solution is used dropwise to determine the amount of acid in the sample. Do not shake vigorously. Store at temperatures above 70 degrees F. Make sure to flush with water when it comes in contact with skin. Read MSDS sheet before using.
2.2 ACID INDICATOR: Bromophenol Blue ( C19H9Br4Na2O5S) M.W. 692.0 g.
3.0 Procedure
3.1 Use 1.0 ml (cc) acid sample or 2.0 ml (cc) rinse water sample. Using the syringe provided add the appropriate size sample to about 20 ml distilled water in the 50 ml flask. Swirl the solution to mix.
3.2 Add 1 -2 drops of Acid indicator.
3.3 Add Acid titrant dropwise, mixing after each drop until solution turns blue..
4.0 Calculations ( Specific Gravity assumed 1.0 g/ml )
4.1 For a 1.0 ml sample each drop is equal to 1.0 % Sulfuric acid or 10,000 ppm.
4.2 For a 2.0 ml sample each drop is equal to 0.5 % Sulfuric acid or 5,000 ppm.
4.3 If testing for HCl ( Hydrochloric Acid) multiply results by 0.74.
4.4 If specific gravity or baume of solution is known determine true %weight acid by the following formula.
Specific gravity g/ml = 145/ ( 145- baume)
True % wt. acid = ( % acid in dropper bottle test X ( 1/specific gravity in grams/ml))
