The best way to help the environment when your ink cartridges have expired is to recycle them by sending them away to be re-manufactured. This involves returning the toner or ink-jet unit to its original state and ready to be reused.
However, if your recycling company will not accept your cartridge then there is an alternative to putting them into the bin. Companies like Innovative Recycling of El-Paso are able to recycle the parts. They strip the unit down and separate the raw materials (plastic, metal etc.) and process them, ready to be used again.
So, don’t give up if you have a refilled cartridge that can’t be accepted for remanufacturing into a new cartridge, you may still be able to recycle the materials from the cartridges.