How To Separate Colors into Layers

I have several icons that I would like to recolor. My thought was to figure out how to normalize and image colors (based around your basic colors, black, white, red, green, orange, blue, yellow, purple, brown). Then I want to separate those colors into their own layer.

By normalize, I mean to make all shades of green actually be green, all blues be one blue, etc...

So I looked at a few ways to accomplish this, but I want to automate the process into an action or filter. In short, I want to create an action that takes all shades of a color and combines them into 1 shade of that main color. Then copies that into its very own layer. Does anyone have an action/filter they want to share or a tool they could suggest. In the end I want a layer for each color:

Transparent
Red
Green
Blue
Yellow
Orange
Purple
Black
White

I have been trying various strategies with channels and got pretty close. I also tried to turn the image to index using a custom Color Table with the colors from above. That got close as well, but the if you had shades of blue and white mixed, it didn't work. Maybe someone else has a good idea?