Sodium Perborate (Mono & Tetra)
Sodium perborate is a white, free-flowing crystalline compounds soluble in water. Sodium Perborate is a stable, solid source of active oxygen.
Sodium perborate exists in the anhydrous , mono, tri and tetrahydrate forms (mono and tetrahydrate forms are important commercially). Sodium perborate tetrahydrate is prepared by reaction of sodium borate with hydrogen peroxide. Sodium perborate releases back hydrogen peroxide, if dissolved in water. Its properties in aqueous solution are practically similar to them of a solution of hydrogen peroxide. Accordingly, sodium perborate is considered as a solid form of hydrogen peroxide used as a strong oxidizing agent in various industry including in detergent.
In comparison with solution of hydrogen peroxide, Solid form of sodium perborate compounds provide better conditions of stability and convenient handling. Sodium perborate monohydrate provides a high available oxygen content equivalent to 32% hydrogen peroxide – 50% more active oxygen than the same weight of sodium perborate tetrahydrate. Its oxidative power improves the cleaning, bleaching, stain removal and deodorizing performance. TAED (Tetraacetyl Ethylenediamine) can be added to lower down working temperature.
The principal sources of boron for the production of sodium perborates are the minerals Kernite, Na2B4O7.4H2O, and Tincal, Na2B4O7.10H2O. Both the mono and tetrahydrate of sodium perborate are used as oxidising and bleaching agents in cleaning, cosmetic and pharmaceutical preparations but their main application is in detergents. Typically a detergent will contain up to 15 wt% of the tetrahydrate and/or up to 10% of the monohydrate. The monohydrate is preferred if rapid solution is required.