Extracting metallic magnesium from cholorphyll My understanding is that when chlorophyll is exposed to an increased concentration of hydrogen ions (or rather the pH is lowered), the magnesium is displaced by a hydrogen ion and chlorophyll is converted to pheophytin.



My question relates to the Mg2+ ion that is released in this process. Is it possible, naturally depending on the acid used to convert the chlorophyll to pheophytin, to isolate the Mg released?

Note my background in chemistry is rather limited. My guess is that the Mg will react to whatever acid (say sulfuric acid) to create a compound like magnesium sulfate which in turn can be processed to extract Mg in metallic form (electrolysis?). 

Any clarity would be much appreciated as this has tickled my curiosity for a while now.
You can make the magnesium salt, but electrolysis of an aqueous solution of this salt will reduce the water, evolving hydrogen, not reduce the magnesium.  You can get metallic magnesium via electrolysis of the molten chloride or high temperature reduction of the oxide with carbon,  neither of these cheap or easy.  See here.