LABORATORY STUDY ON BIOXY S

Surviving germs: Green (0.5 g/L BIOXY S) - Orange (0.3 g/L Sodium percarbonate) - without additive; after 15 minutes at 25°C

Biocidal efficiency of the BIOXY S
The antimicrobial action of peracetic acid and of hydrogen peroxide has long been known. While peracetic acid displays effective bactericidal, viricidal and fungicidal properties, hydrogen peroxide has a particularly antiseptic and bacteriostatic action. Its sporicidal properties are also to be emphasized. Both supplement each other ideally.

Both perborates and percarbonate are suitable as a source for hydrogen peroxide. 95% of the microorganisms are destroyed by the persalt, but destruction rates of >99.99% are achieved only by the addition of BIOXY S. Even at temperatures below 40°C, where the activity of hydrogen peroxide - in particular is not very good, the efficiency can be improved by using BIOXY S and the spectrum of activity can be broadened considerably.

BIOXY S displays excellent effectiveness towards a wide spectrum of pathologically active germs. This is true especially with low application temperatures and short reaction times. At room temperature no significant effect is established with percarbonate alone.

BIOXY S results in effective destruction (> 99.99%) even with contact times of less than 15 minutes. This is particularly of interest in countries with cold wash conditions or for the use in disinfectants.

Also effective against yeast fungi
The yeast fungus candida albicans proves to be particularly stubborn when treated with oxygen releasing disinfectants. Its growth is hardly impaired by detergents without any bleaching system. Even at 40°C the addition of perborate alone does not lead to the desired effect. A significant reduction in germs even at 40°C can be achieved BIOXY S.

Effective sterilization
The antimicrobial activity of the BIOXY S system starts even under cold wash conditions. Under these conditions perborates or hydrogen peroxide alone only display inadequate action.

BIOXY S in the environment
BIOXY S is especially environmentally friendly when combined with percarbonate. In the process it is decomposed into diacetylethylenediamine (DAED) and peracetic acid (PAA), which is reduced to acetic acid. If excess peracetic acid gets into the effluent, it is decomposed catalytically by metal traces instantaneously. DAED is mineralized within a short time. Environmentally friendly percarbonate is decomposed in the washing process into sodium carbonate and hydrogen peroxide, out of which water is formed following the transfer of oxygen.

Biological degradability of BIOXY S
The biodegradability of BIOXY S was investigated in numerous different tests. Degradation values >95% within 28 days' test duration prove their rapid degradation free of metabolites. BIOXY S is therefore to be classified as easily biodegradable according to the OECD. The occurrence of acetylethylenediamine or free ethylenediamine as an interim stage of the degradation was ruled out by analytical methods.

Ecotoxicological data of BIOXY S
BIOXY S must be considered for an ecological assessment. The LC50 values towards water organisms which were observed prove that they are uncomplicated compounds with regard to acute toxicity. BIOXY S is classified in water hazard class 0. Sequestration, heavy metal remobilization or metal fixation are not observed with BIOXY S nor with DAED.

Mechanism of the perhydrolysis
On dissolving the persalts in water, hydrogen peroxide is released, which rapidly dissociates under the alkaline conditions of the washing liquor. The formation of perhydroxyl anions necessary for the perhydrolysis stage is promoted by a high pH value (pKa H2O2 : 11.3).

Two molecules of peracetic acid are released by nucleophilic attack of the OOH- ions on the instable imide bonds of the TAED molecule in BIOXY S. Since the perhydrolysis takes place much more quickly than a hydrolysis reaction, this side reaction can be largely excluded, providing the pH value is below 11. The formation of diacyl peroxide is not observed when using BIOXY S.