I've used an iodine solution called "Lugol" (bought it this way from a pharmacy in Begium) that would remove the silver from the emulsion. I applied it, a few seconds after the paper would turn yellow and a few minutes after I could wash, fix and rewash the paper to remove the yellow stain. What remained was white. Used it on glossy FB quite successfuly.
After a quick search on the net, I found that Lugol consists of 5g iodine, 10g potassium iodide in 100ml of water. It's a disinfectant solution.
Household bleach (chlorine bleach) will remove ALL the emulsion from the paper, leaving it bald (you'll be able to see the actual fiber base we talk so much about). Chlorine is radical (and dangerous to use) for if you get some of it apilled on a part of the print you don't want it, it'll be too late for tears... Use it cautiously.
Otherwise, you can use one of the known photographic bleach solutions.
Here are a couple of images I artificially "aged" using a dilute solution of household chlorine bleach. I sprayed the bleach, then stopped the process by spraying water.