<p>These workers are paving an airport runway with a material derived from cashew shells. The sustainable asphalt concrete is being put to the test at Germany's Frankfurt Airport, which is trying to achieve a goal of zero carbon emissions by 2045. Conventional asphalt concrete is made by mixing bitumen, a by-product of crude oil processing, with aggregates. German start-up B2SQUARE has created an eco-friendly version it calls “BioBitumen".</p> <p>The company creates its organic bitumen by mixing naturally occurring hydrocarbon resin with an organic extract from cashew shells, according to the Frankfurt Airport.</p> <p>Frankfurt Airport Services' project manager Axel Konrad says this means the quality is higher than traditional bitumen.:: Axel Konrad, Project manager, Frankfurt Airport Services "So, for us, two points are very important at this stage. Firstly, the quality, which we expect to get a higher, much higher quality from this organic bitumen, because we are no longer subject to these fluctuations in the quality of the bitumen that is produced from crude oil. And the second point is, of course, the CO2 balance. We assume that the road will then be at least CO2 neutral."</p> <p>B2SQUARE says their "BioBitumen" stores around 3,400 pounds of CO2 per 2,200 pounds of bitumen, thanks to the CO2 captured in the cashew shells... and that the material is ten times more durable than conventional bitumen. To see how the two materials hold up, the Frankfurt Airport is paving one side of a 650-foot-long road with bioasphalt and the other side with regular asphalt. If the test is successful, the bioasphalt will contribute to the airport’s green transition.</p>