https://phys.org/news/2018-05-gas-masks-sports-equipment.html

'At the end of the building or renovating you probably have fibreboard as waste and, at this point, it's not recyclable—it's only burnt or landfilled,' explained Dr. Vanreppelen. 'But we've developed a process to use it to make a product called activated carbon, which is used as a filter in water purifiers or gas masks.'

Waste from the construction industry accounts for around half of the 1.3 billion tonnes of solid waste that cities produce globally every year. This is roughly equivalent to the amount of material inside 4.5 million single-storey homes – enough to house almost the entire population of Belgium.