X-rays should not be put in your recycling bin at home. They can only be recycled through specialised recycling services.
Some organisations have recycling collection points for x-rays. If you cannot find an organisation that collects x-rays in your area, check with your council to see if there are other options. Otherwise, they can be put in your garbage bin.
X-ray films contain silver in the form of halides, which can be extracted and converted into pure silver.