so I have a friend whose husband is allergic to coconut oil etc. & i've used coconut oil in my silicone mold in the past, is it possible to clean the mold so no trace amounts of coconut oil remain before using the mold to make a lard soap recipe?
Honestly if it is a severe allergy I would not risk it. I'm sure it is possible but if you left even a hint behind and his allergy were severe enough . . . Well I just would use a different mold and avoid all doubt. If you use a wooden mold (or loaf) mold you can easily line it with freezer paper to be sure it is "fresh" for each batch.
I would use a different mold. Some allergies, mine for instance, are severe enough that if a person used a mould that had held shea butter soap in it and I used a non shea butter soap, I would react to it.
You can get a drawer organizer at the dollar store, they make great back up log molds and you could keep it specifically for coconut free soap. They come in all sorts of sizes, I had the blue one until I forgot to grease it with mineral oil and had to cut it off my soap.
I use those blue drawer organizers for molds occasionally. I have never lined or greased them, just pull the sides away from the soap, then turn them upside down and press firmly(think CPR firmness) in the center, while pulling up on one end, then the other. The loaf generally just pops out. I guess I just lucked out on not having to cut one off so far.
But yes, those make good molds that are cheap enough that you can designate one "NO CO" forever. They hold 3 lbs of soap. (so 2 lb oil in the batch)
Is the stick blender plastic or stainless? If its stainless, you might be able to sterilize it some how or maybe you could find a back up blender at a thrift store (or ask friend to purchase a cheap one for you).
It would probably be safe to clean your SB if its a mild allergy but thats something you should discuses with your friend, maybe have them run it by their doctor. If its a severe allergy, I would go with all new equipment.
In high glass of cup pour hot water then a drop of two of dishwashing soap. Keep the SB on low for some time, change the water and do it again , then do it in warm water without soap , then you good to go. I also spray my stick blender (but is the separate for lotion with alcohol) )
cheap SB are not tight nor stainless steel, so very difficult to wash, and the soap goes up when before tracing. It is not good idea, only if she keeps one for no CO then , who knows how it was used for, if it is the one bought in Salvation army....
Better safe than sorry