Waste

Hydrogen sulfide famously stinks like rotten eggs. It's also toxic, corrosive, flammable and produced in large amounts as an expensive by-product at petroleum refineries. Now, researchers have found an easy, profitable way to turn it into hydrogen.

As compared to traditional agriculture, hydroponic farming uses less space and less water, plus it requires no soil. It still does require a growth medium, though – and scientists have recently created a better such medium, derived from human hair.

Discarded electronics can be a gold mine – literally. Researchers have developed an efficient new way to use graphene to recover gold from electronic waste, without needing any other chemicals or energy.

The production of cement is a major source of carbon emissions, so the less of it that's used, the better. A new study could help, as it shows that cement can be made much stronger with the addition of material derived from waste shrimp shells.

Construction is one of the largest sources of greenhouse gas emissions. Flinders University researchers have now developed a polymer made out of industrial waste that can be formed into building bricks that bond together without needing any mortar.

Nanoracks, in conjunction with NASA's Johnson Space Center, has successfully expelled 172 lb (78 kg) of trash from the ISS in a high-tech bin liner that was ejected from the station's Bishop Airlock on June 2 to then burn up in the atmosphere.

In a typical poultry processing facility, much of the waste is simply dumped in a landfill or burned. Two new processes, however, make use of the feathers, blood and bones – plus one of them may ironically reduce the number of chickens slaughtered.

We need to get creative with recycling. In a new study, researchers at Rice University and Ford’s Research and Innovation Center have demonstrated how waste plastic from old cars could be used to make graphene foam that can then be used in new cars.

Changing up the recipe could help roads last longer. Researchers in Australia have now shown another advantage of adding rubber from old tires to asphalt – extra Sun protection that could help roads last up to twice as long before cracking.

The production of traditional Portland cement is a major source of greenhouse gas emissions, as the ingredients have to be heated to very high temperatures. Such is not the case with a new biocement, however, which also incorporates waste materials.

As important as face masks are in our current pandemic-riddled world, they have a major environmental impact. Now scientists have demonstrated a novel method for disposing of old masks by using them to make low-cost, flexible and efficient batteries.

Composed of calcium sulfate dihydrate, gypsum is a naturally occurring mineral used in building materials. Scientists have now devised a method of creating synthetic gypsum, which should be more energy efficient than processing the genuine article.