Sorry if this is a repeat- but read the handbook and see no real mention about recipes- can you trade them, sell them, give them to friends in your shared trunk some how? What to do with the extras- just ignore them- but i sure would like the gold! ;}
The trade of items other than non-enchanted Treasure Cards is not and will not be a part of Wizard101.
Once you have learned a recipe, it stays on that character. Recipes cannot be sold, deleted or placed in the bank. Think of it like a real recipe, once you know how to make Mac & Cheese, you never forget!