[jmarjorie]

Dear All,

I was given a formulation of a biocide which did not
seem correct and wanted your kind opinion on it.
The ingredients are given below and I have mentioned points that contradict the formulation.
Please give me your views on it. Thanks.

                                               % VOL
1) LABSA                                      15
2) SLES                                          7
3) Perfumes                                   0.01
4) Water                                       60.78
5) Benzalkonium Hydrochloride         0.21
6) Caustic (sodium hydroxide)          5
7) Sodium hypochlorite                    2.5
Sodium gluconate                       4.5
9) Paracetic acid                             5
                                                ------
                                                100
                                                ------

   pH                                3.91
   Electrical conductivity      11.17 uSi
   Active Detergent Index     8.3%

                   C O M M E N T S

A) CAUSTIC (sodium hydroxide) :
   i) Cannot exist as free NaOH as this would  
   react with LABSA, to give the sodium salt of LABSA.
   ii) Will react with the Hydrochloride moiety of  
   Benzalkonium hydrochloride
   iii) Will react with the Paracetic acid, to give
   the sodium salt
   iv) Should be alkaline(pH 7.5 - 14) whereas the pH
   of the solution is given as 3.91 (acidic)

B) SODIUM HYPOCHLORITE :
    i) Will react vigorously with the paracetic acid
    ii) Is not stable in acidic environments

C) BENZALKONIUM HYDROCHLORIDE :
   The concentration is TOO small for it to exert any

   biocidal activity.

D) PARACETIC ACID :
   Addition of external sod.hypochlorite to a solution

   containing Paracetic acid should give rise to a
   vigorous effervescence. There was none, with the
   inference that no 'Paracetic acid' is present

E) INTERACTIONS OF INGREDIENTS
   LABSA & SLES are anionic surfactants, whereas the
   Benzalkonium hcl is a cationic surfactant.
   The two would react together and precipitate.

   jmarjorie
   chemicals555@yahoo.com