Block saving item

So if you know the pillars from mystical agriculture, they let you place items on them and it renders them above it which can then be used to craft something. I am looking for a way to do the same thing but with 1 block, where I would have a recharge station and I can place an item on it which will render in a certain place and get recharged. I know how to do the recharging part but I do not know how to:

A) render the item

B) restrict it to a certain selection on items

C) detect the item

Any help would be appreciated