German airport tests cashew-based asphalt in green push

A sustainable asphalt mix made from cashew shells is being tested at Frankfurt Airport in Germany, which aims to achieve zero carbon emissions by 2045. Conventional asphalt paving is made by mixing bitumen, a byproduct of crude oil processing, with aggregates. German startup B2Square has created an eco-friendly version it calls BioBitumen. The company creates its organic bitumen by mixing naturally occurring hydrocarbon resin with an organic extract from cashew shells.

Class discussion: Do we need to find materials with lower carbon emissions to construct our buildings, infrastructure, and consumer goods? Does it make sense to make asphalt from the waste of food production instead of a byproduct of oil production? The most common building material is concrete, made of aggregates mixed with cement produced in kilns that release 8 percent of the world’s carbon dioxide emissions. Are there any substitutes for this favorite building material?