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Iron oxide nanoproducts include magnetic and non-magnetic crystals. The magnetic crystals could be incorporated into plastic drink bottles and other consumer packaging to enable separation of co-mingled recyclables using magnets, similar to steel cans.

The lightweight plastic grocery bags that are so difficult to keep in the working face at solid waste disposal facilities during windy days could be produced with iron oxide nanomaterials to better capture these plastic grocery bags using electro-magnets located adjacent to the working face (similar to litter fences).

Using iron oxide to treat landfill gas containing elevated levels of hydrogen sulfide (i.e. the iron sponge) is not a new idea. However, the availability of nanoproducts and their incredibly large surface area (about 320 square meters covered by 1 gram), which is a valuable characteristic of such materials, allows for new methods of application for landfill gas treatment, such as down-well or in-waste rather than the traditional filter media.

Similar to how geosynthetic clay liners incorporate a low permeability clay product sandwiched between two geotextiles sewn together, carbon nanotubes, called “fulerenes,” could be attached to the geosynthetic layers of a landfill bottom liner system to provide pre-treatment of leachate collected at the bottom of the landfill.

In anaerobic environments, the potential for elevated ammonia concentrations to build up in the leachate may require bioreactor landfills to treat leachate to be recirculated. Rather than operating a nitrification pretreatment plant, nanomaterials may be able to provide a forum for chemoautotrophic bacteria to yield high nitrate-containing leachate for distribution into the wastes. These same nanoproducts may provide extensive surface areas to support the facultative heterotrophic bacteria within the wastes to perform denitrification.

Incorporating the use of nanomaterials as alternate daily covers at landfills may prove difficult because of challenges with application onto the working face; however, the ability for such nanoproducts to enhance the distribution of beneficial microbial populations in order to accelerate landfill waste stability and enhance the biochemical methane potential will likely encourage the waste industry to pursue such activities.