Where the
world gathers for metal finishing
Q&As since 1989


-----

Determination of silver concentration in ppm levels

2004

Hello,

I have an aqueous medium in which silver is in ppm levels. How can I determine the silver concentration in the medium using a simple chemical analytic technique. I can evaporate the medium to concentrate the silver content too.

Thanks in advance.

Vikram Daga
Graduate student - Newark, Delaware, USA

Sounds like an application for atomic absorption [on eBay or Amazon] analysis. Doesn't your college have one of these units?

Steve Bizub
- St Louis, Missouri
2004

---

2004

If you have access to a spectrophotometer or to a colorimeter with a 465 nm filter, you may be able to use a simple procedure based on the absorbance of the silver-dithizone complex for determination down to sub-ppm levels. See details in "Colorimetric Analysis of Metal Finishing & Metal Working Solutions and Effluents" by Aubrey Knowles. That method is simple but suffers from many interferences (copper, various precious metals, etc.). A somewhat more selective method, reducing copper interference in particular and based on the same chemistry, is described in "Colorimetric Methods of Analysis" vol. IIA by Snell, Snell & Snell (yes indeed!), Van Nostrand, NY 1959.

Emanuel I. Cooper
- Yorktown Heights, New York