Back to Ganoksin | FAQ | Contact

Cleaning silver with sulphamic acid


#1

Recently I tried a new cleaning solution of Sulphamic Acid on my
silver wire the results are spotty to say the least. The wire has
some
melted old rubber (from rubber bands) on it where I secured it to
the spool now I can’t get it off. Some tarnish has appeared
too…still stubornly not removed by my vibrasonic cleaner. I am
using hot water and ajax cleanser I’m so frustrated with the lack of
results. Oh, some tumbler grit (fine) as well. I can’t think of what
else to try. Some of the wire I tried cleaning with the sulphamic
acid and now, I have a fine copper coloured scall in spots hat will
not rub or polishof with a cloth.

Any ideas are certainly appreciated.
Thanks, I love this site!


#2

Put your wire into a small amount of pickle and add a “slug” of
hydrogen peroxide. This will remove the pink and the tarnish. It is a
strong pickle and can etch solder so the object needs to be closely
watched if it is fabricated. This solution does not last long and can
be poured back in the pickle pot when you are done.

marilyn


#3
Recently I tried a new cleaning solution of Sulphamic Acid on my
silver wire the results are spotty to say the least. The wire has 

Is “sulphamic” acid the same as sulphuric acid? Similar? What is it?

Just curious…


#4
Is "sulphamic" acid the same as sulphuric acid? Similar? What is
it? 

see: http://en.wikipedia.org/wiki/Sulfamic_acid

  Sulfamic acid, also known as amidosulfonic acid, amidosulfuric
  acid, aminosulfonic acid, and sulfamidic acid, is a molecular
  compound with the formula H3NSO3. This colorless,
  water-soluble compound finds many applications. 

  Sulfamic acid (H3NSO3) may be considered an intermediate
  compound between sulfuric acid (H2SO4), and sulfamide
  (H4N2SO2), effectively - though see below - replacing an -OH
  group with an -NH2 group at each step. This pattern can extend
  no further in either direction without breaking down the -SO2
  group. 

jesse


#5

Sulfamic acid is most common to water descaling componds/products as
they are effective at removing the whitish ( lime) scale found on
glassware. It decomposes at the boiling point and evaporates and you
may encounter a mild ammonia scent if you heat it to the boil- in any
case you should not be heating pickle to that point. It is not the
same as sulphuric acid- urea,is more equivalent. In fact sulfamic
acid is closer to hydrochloric acid than sulfuric acid. It is
commonly used in the synthesis of sweeteners like acesulfame
potassium ( or Equal brand name sweetener for instance), and in
things that fizz on contact with H2O (Johnson and Johnson
"Fizz-it’s" toilet bowl cleaning tabs, shower and bath "fizzing"
tabs, etc) as an alternative to an acid/ sodium bicarbonate compound
(for instance mixing vinegar with baking soda produces copious
fizzing). A more effective cleaner for silver is cigarette ash and a
paper towel dampened then dipped into it- the results are instant and
a rinse is all that’s needed to see a brilliant shine return to fine
or sterling silver -even badly blackened or firescaled material.


#6
Is "sulphamic" acid the same as sulphuric acid? Similar? What is 
it? 

No, sulphuric acid has the formla H2SO4, and sulphamic acid has the
formula H3NSO3. Sulphuric acid is a strong acid and sulphamic is a
weak acid. Don’t confuse weak and strong acids with acid dilution/
concentration. Strong acids dissociate completely in aqueous
solution to release all its hydrogen ions. The reaction goes in the
forwards direction only. Weak acids only partially dissociate in
aqueous solution, only releasing some of its hydrogen ions. The
reaction goes in both directions - reversible reaction - but the
forward reaction is favoured.

Helen
UK


#7
Is "sulphamic" acid the same as sulphuric acid? Similar? What is
it? Just curious 

Sulphamic acid is an organic acid long used for cleaning scale from
heat exchanger tubes, as in distilling plants aboard ships at sea.
It is a weak acid, as it doesn’t ionize as completely as sulfuric
acid does. It is more like citric acid in its behavior. It is great
for removing lime buildup; I never saw it used for cleaning metals,
but it can substitute for hydrochloric acid for rust removal.

Dick Davies