Product Knowledge Article

The qualified ammonium bisulfite products shall comply with the requirements specified in Table 1.

This standard specifies the requirements, test methods and the labeling, packaging and other aspects of industrial ammonium bisulfite.

Marking, Packaging, Transportation, and Storage

Each batch of ammonium sulfite in solid or liquid form leaving the factory shall undergo inspection by the quality supervision and inspection department of the manufacturing enterprise to ensure all product specifications comply with this standard.

Solid ammonium sulfite shall generally be produced in batches corresponding to the same specification of finished product quantity on the same day

Determination of Ammonium Sulfite Mass Fraction

If the sample contains ammonium bicarbonate, the mass fraction of ammonium sulfate [(NH4)2SO4] (expressed as%) shall be calculated using Equation

In solution A (4.2.2.3) after ammonium bisulfite determination, add one drop of methyl red indicator (4.2.5.2.5). The solution turns red. Adjust to red with sodium hydroxide solution

In the test sample, ammonium sulfate reacts with formaldehyde to form hexamethylenetetramine and sulfuric acid in stoichiometric amounts with ammonium sulfate.

Weigh approximately 0.5g of the sample quickly using the difference subtraction method, with precision to 0.0001g. Transfer the sample to a 250ml Erlenmeyer flask containing 15ml hydrogen peroxide solution (4.2.4.2.1) and about 30ml water, and shake well.