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Q&As since 1989


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Are sulfuric, nitric and hydrophloric acids available in powder form?

We have stainless steel re-rolling units in Delhi(India). For picking of sheets we use solution of sulfuric+nirtric+HF+water in certain proportion. these chemicals are supplied to us in liquid form. I want to know if these chmicals are available in powder form and can these be used by simply adding to water?

SANTOSH AGGARWAL
STEEL - New Delhi, INDIA
2005

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No, they are all liquids.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK

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First of two simultaneous responses --

Not economically feasible! You can substitute ammonium bi fluoride-a salt or crystal for the fluoride to avoid the extremely hazardous HF. To reduce problems with the nitric and the sulfuric, buy it is lower strength (baumé) and use no or less water. Any acid in full strength and large quantities is a risk. This is offset by stringent enforcement of proper protective equipment and handling procedures.

James Watts
- Navarre, Florida
2005
2005

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Second of two simultaneous responses --

Some mineral acids (i.e. boric) and many organic acids crystallize and can be acquired in powder form. But, no matter how concentrated, all of your mentioned acids are always liquid. You may want to investigate and learn more about acid salts which sometimes may be used instead of them.

Guillermo Marrufo
Monterrey, NL, Mexico
2005

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Sulfuric acid is available as the acid salt sodium bisulphate. When dissolved in water becomes sulfuric acid. It is commonly used for all applications where sulfuric acid is selected. Use from 60 g/L to 120 g/L depending on the strength of sulfuric acid you need.

Don Baudrand
Consultant - Poulsbo, Washington
(Don is co-author of "Plating on Plastics" [on Amazon or AbeBooks affil links]
           and "Plating ABS Plastics" [on Amazon or eBay or AbeBooks affil links])
2005