Analytical Test Methods Revisited
In my March 2005 column, I answered a question regarding analytical test methods. I realized after answering the question that my response to the question was too narrow in scope. There are a few additional comments that should be made: In particular the usefulness of instrumentation methods for maintaining clean plating baths. To refresh your memory here is the original question and my response.
We are setting up a new analytical laboratory. Where can I find written procedures for the various tests that are required for maintaining the plating line? M. M.
There are a number of sources and information that are readily available. The first place for you to go is the companies that sell you your plating chemicals. Almost all of these companies will have available standard analytical procedures for testing of the various components in plating baths.
There are two reference books available that contain the information that you are looking for. They are Volumetric Analysis of Metal Finishing Solutions by Andrew McFadyen and Colorimetric Analysis of Metal Finishing & Metal Working Solutions and Effluents by Aubry Knowles. Both books are available from ASM International, www.asm-intl.org.
There is nothing wrong with using classic "wet chemistry" methods for monitoring various components in a bath. Many metal finishing operations use such methods but if there are many plating baths the wet chemistry methods become rather tedious.
Instrumentation methods of various types can come to the rescue and are used in many larger laboratories. If you look in the Products Finishing 2005 Directory and Technology Guide under Analytical Equipment, you will find a number of different categories of instruments. You can do the same by accessing www.pfonline.com and searching the supplier database. Yes, instrumentation can be a bit pricey but there are instrumentation methods available that will not break the bank.
Automatic titration equipment is one such method. Other instrumentation methods such as atomic absorption and ion chromatography are more expensive to set up but will be cost effective in many applications.