Determination of Total Free Alkalinity

Developed by the International Standards Organization (ISO) The ISO 684 standard provides a test method for determining the total free alkaline content of commercial soaps, excluding compounded products. If the soap contains additives that can be decomposed by sulfuric acid (for example, alkali silicates and the like), the method described in this standard is not applicable. This method cannot be applied to some colored soaps.

In the application of the mentioned standard, the total free alkali content is the sum of the free caustic alkali and free carbonate alkali contents. Results are usually expressed as mass percent of sodium hydroxide for sodium soaps or potassium hydroxide for potassium soaps. It can also be expressed as milli equivalents per gram.

In this test method, the sample is dissolved in alcohol and titrated against standard acid. In another test method, the sample is refluxed in alcohol and titrated with standard acid. In both cases, if the product contains mixtures of sodium and potassium hydroxide, the free alkali content It should not exceed 2.5 percent by mass.

Essentially, the pH value is the amount of hydrogen in the product. The higher the hydrogen content, the higher the pH value. A high pH value means that the product is basic, that is, alkaline.

In the tests and analyzes carried out in our organization, which has a wide range of technological equipment, trained and experienced staff and applies the most modern methods, national and international standards and legal regulations in force are complied with. Among the numerous tests performed in this context, there are also services for the determination of total free alkalinity.