Water filters are generally made of plastics and activated carbon. So this means it is a composite material.
This should be placed in the general waste bin.
Water filters cannot be recycled as part of your recycling collection scheme nor at Civic Amenity Sites. However, if you use a BRITA branded water filter you can recycle the used filters at most Argos and Homebase stores where boxes are provided for the collection of used cartridges.
TerraCycle® and Aqua Optima® have partnered to create a free recycling programme for all your Aqua Optima® water filters. The programme also offers participants the opportunity to fundraise for their favourite school or charity. Check HERE