Determination of Available Chlorine Content in Trichloroisocyanuric Acid by Titration

Required materials and tools

1. Soluble starch

2. Concentrated sulfuric acid

3. 2000ml Beaker

4. 350ml beaker

5. Weighing paper and electronic scales

6. Purified water

7. Sodium thiosulfate analytical reagent

Preparing stock solution of sodium thiosulfate

Measure 1000ml purified water by using 500ml measuring cups twice and pour it into a 2000ml breaker.

Then pour a whole bottle of sodium thiosulfate analytical reagent into the beaker directly, Put the beaker on the induction cooker until the solution boils for ten minutes.

After that, Keep it cool, and still for two weeks, then filter it to get the stock solution of sodium thiosulfate.

Preparing 1+5 sulfuric acid

Measure 750ml purified water by using 500ml measuring cup twice and pour it into 1000ml wild-mouth bottle.

Then measure 150ml concentrated sulfuric acid, Pour the acid into purified water slowly, Stir it all the time when pouring.

Prepare 10g/L starch solution

Measure 100ml purified water by using 100ml measuring cup, And pour it into 300ml beaker.

Measure 1g soluble starch in electronic scale, And put it into 50ml beaker. Take the 300ml beaker on induction cooker to make the water boil.

Pour little purified water to dissolve the starch, Then pour dissolved starch into boiling purified water, Keep it cool for use.

Steps for measuring content of Trichloroisocyanuric acid

Take 100ml purified water Into 250ml iodine flask.

Measure 0.1g TCCA sample in precision scale, Make it accurate to 0.001g, Put the sample directly into 250ml iodine flask.

Measure 2g potassium iodide into iodine flask, And also put into 20ml of 20% sulfuric acid, Then seal the flask by water after cleaning the flask neck by cleaning bottle.

Make it into ultrasonic wave Which dissolve it totally, After that, clean the bottle neck using purified water again.

The last step is to titrate with standard titration solution of Sodium thiosulfate, until the solution are in light yellow color put 2ml starch tracer agent. And keep titrating until the blue color just disappear Then we can finish it.

Record the volume of consumed sodium thiosulfate

Make a black experiment at the same time

Calculating process of assay results