What kind of metal in a food strainer?
 

I had a bunch of crud in my muriatic de-rust bucket & I strained it
through a (old) kitchen strainer. You know, the woven-wire basket with
a handle kind.

I thought it was made with SS wire, but I got a very vigorous reaction
with the acid. WTF! I know the wire isn't aluminum, it couldn't be
zinc (food contact), what is it? Tin? Does tin react with HCl? Would
they make strainers with pure tin, not tin coated steel? If so,
wouldn't SS be cheaper (I found tin ingots on the web for $12/lb)?

Puzzled,
Bob

What kind of metal in a food strainer?
 

On Jan 20, 8:20*am, Bob Engelhardt wrote:
I had a bunch of crud in my muriatic de-rust bucket & I strained it
through a (old) kitchen strainer. *You know, the woven-wire basket with
a handle kind.

I thought it was made with SS wire, but I got a very vigorous reaction
with the acid. *WTF! *I know the wire isn't aluminum, it couldn't be
zinc (food contact), what is it? *Tin? *Does tin react with HCl? *Would
they make strainers with pure tin, not tin coated steel? *If so,
wouldn't SS be cheaper (I found tin ingots on the web for $12/lb)?

Puzzled,
Bob

Yup, makes stannous choride. See if a magnet sticks. Most food-grade
stainless items are the non-magetic sort. And the iron underneath the
tin will react with the hydrochloric acid pretty quickly, too. Sounds
like you'll need a new strainer. The tin coating was in the
fractional mil range, if the item isn't too old, can make a whole lot
of coated wire per pound at that sort of thickness.

Stan

What kind of metal in a food strainer?
 

What kind of metal in a food strainer?
 

On Jan 20, 11:37*am, Bob Engelhardt wrote:
wrote:
... *See if a magnet sticks. * Most food-grade
stainless items are the non-magetic sort. *

A magnet doesn't stick, but it's definitely not SS. *SS doesn't react
like this with HCl.

And the iron underneath the

tin will react with the hydrochloric acid pretty quickly, too. *...

Iron doesn't react as vigorously as this does. *It was "boiling" away to
the end, not just while a coating was being reacted.

Bob

In a lab I worked the two most common types of sieves that we used
were stainless steel and brass. The brass ones were less expensive.
I'll bet that the strainer was a tinned or plated brass.

What kind of metal in a food strainer?
 

On Jan 20, 2:53*pm, "Denis G." wrote:
On Jan 20, 11:37*am, Bob Engelhardt wrote:

wrote:
... *See if a magnet sticks. * Most food-grade
stainless items are the non-magetic sort. *

A magnet doesn't stick, but it's definitely not SS. *SS doesn't react
like this with HCl.

And the iron underneath the

tin will react with the hydrochloric acid pretty quickly, too. *...

Iron doesn't react as vigorously as this does. *It was "boiling" away to
the end, not just while a coating was being reacted.

Bob

In a lab I worked the two most common types of sieves that we used
were stainless steel and brass. *The brass ones were less expensive.
I'll bet that the strainer was a tinned or plated brass.

Hadn't thought about brass, if the acid coming off was blue or green
you're probably right. Guess my strainers are cheaper than that,
even. Have a few inherited ones that are getting rusty, but good
enough for cleaning small parts, not for kitchen duty.

Stan

What kind of metal in a food strainer?
 

On Wed, 20 Jan 2010 10:20:14 -0500, Bob Engelhardt
wrote:

I had a bunch of crud in my muriatic de-rust bucket & I strained it
through a (old) kitchen strainer. You know, the woven-wire basket with
a handle kind.

I thought it was made with SS wire, but I got a very vigorous reaction
with the acid. WTF! I know the wire isn't aluminum, it couldn't be
zinc (food contact), what is it? Tin? Does tin react with HCl? Would
they make strainers with pure tin, not tin coated steel? If so,
wouldn't SS be cheaper (I found tin ingots on the web for $12/lb)?

Puzzled,
Bob

Puzzled too. How do you know that the wire isn't aluminum?

Iron/steel usually requires elevated temperatures to react with HCl at
any reasonable rate.

When the wire reacts with clean muriatic acid, is the solution
colored?

Terry

What kind of metal in a food strainer?
 

On Jan 20, 6:12*pm, Terry wrote:
On Wed, 20 Jan 2010 10:20:14 -0500, Bob Engelhardt
...
Puzzled too. *How do you know that the wire isn't aluminum?

Terry

If it is aluminum, lye (sodium hydroxide) will make it fizz.

jsw

What kind of metal in a food strainer?
 

On Wed, 20 Jan 2010 15:18:03 -0800 (PST), Jim Wilkins
wrote:

On Jan 20, 6:12*pm, Terry wrote:
On Wed, 20 Jan 2010 10:20:14 -0500, Bob Engelhardt
...
Puzzled too. *How do you know that the wire isn't aluminum?

Terry

If it is aluminum, lye (sodium hydroxide) will make it fizz.

jsw

A reasonable test. Something else just came to mind: does the wire
fizz with new, clean HCl? If so then I'm stumped (for the moment at
least). If not, it may be that the crud in the old HCl has gunk** in
it that makes it capable of dissolving stainless steel. Nitrates or
possibly sulfates.

Terry
**A technical term used often in chemistry. :-)

What kind of metal in a food strainer?
 

"Bob Engelhardt" wrote in message
...
I had a bunch of crud in my muriatic de-rust bucket & I strained it through
a (old) kitchen strainer. You know, the woven-wire basket with a handle
kind.

I thought it was made with SS wire, but I got a very vigorous reaction
with the acid. WTF! I know the wire isn't aluminum, it couldn't be zinc
(food contact), what is it? Tin? Does tin react with HCl? Would they
make strainers with pure tin, not tin coated steel? If so, wouldn't SS be
cheaper (I found tin ingots on the web for $12/lb)?

Puzzled,
Bob

Older, or cheaper food strainers are made of tin-plated steel wire. Newer
and/or better ones are made of stainless.

Tin reacts with HCl, but not vigorously. The dilution usually called
"muriatic" will strip the tin off of old tin cans but it actually attacks
the steel more aggressively, so you get a mottled result. The tin will
disappear before the steel can is perforated. Or the old ones behaved that
way.

I learned that by trying to strip the tin off of some tin-can metal, several
decades ago. I used hardware-store muriatic acid.

--
Ed Huntress

What kind of metal in a food strainer?
 

On Jan 21, 1:12*pm, Terry wrote:
On Wed, 20 Jan 2010 15:18:03 -0800 (PST), Jim Wilkins
...
A reasonable test. *Something else just came to mind: *does the wire
fizz with new, clean HCl? *If so then I'm stumped (for the moment at
least). *If not, it may be that the crud in the old HCl has gunk** in
it that makes it capable of dissolving stainless steel. *Nitrates or
possibly sulfates.

Terry
**A technical term used often in chemistry. *:-)

Gunk isn't the same as crud:
http://en.wikipedia.org/wiki/Chalk_r...ified_deposits

jsw