Piranha safe use protocol

[Beinn Muir]

Dear SpecMat Committee,

In our lab in Chemical Engineering we are in the process of putting  
together a safety protocol for the use of sulfuric acid : hydrogen  
peroxide solution in organic contamination removal.

We would be very interested if you could email us details of the  
protocols in place at the SNF for H2SO4:H2O2 preparation, including  
the concentration of reagents, and the addition order. As far as I  
understand, the standard procedure is to add the peroxide to the acid,  
something which goes against the usual "always add acid procedure",  
and we would like to know specific reasons for this. In particular,  
whether the addition of peroxide to acid is also applicable to  use of  
small volumes of the cleaning solution (ca. 100 mL).

Thanks in advance for your assistance.

Best regards,
Beinn...


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Dr Beinn Muir
Department of Chemical Engineering
Stauffer III, Rm113
Stanford University
Stanford, CA 94305, USA
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