Oysters meet increasing demand for sustainability in rubber industry

NUREMBERG, Germany—To help address increasing demand for sustainability in the rubber industry, German distributor Biesterfeld A.G. has started to market a new filler product made from oyster shells.

The bio-based CaCO3 filler, branded Oysterlean, is produced from shells which are a waste material at oyster farms during the harvesting season.

The product can replace carbon black in rubber products by up to 50 percent, offering an 80- to 90-percent lower carbon footprint, said Sascha Hennig, managing director of Biesterfeld Performance Rubber.

CaCO3 is basically calcareous sediment transformed into hard rocks, Hennig said in an interview with European Rubber Journal at the recent DKT expo in Nuremberg.

Oysterlean, he said, is a "proven" bio-renewable material according to ASTM D6866 containing carbon-14 (C14), bio calcium carbonate and chitin.

The material is currently being produced by Swedish Eco SP AroraTek International AB in Taiwan.

"They collect the raw material from official oyster shell dumps where the waters are very pure. That's why the CaCO3 content is 100 percent," the Biesterfeld official added.

AroraTek currently has the capacity to process 40,000-50,000 metric tons of oyster shell per year, an equivalent of 30,000-35,000 metric tons of the refined Oysterlean product.

The company is also planning to build a new production facility in Mexico in the near future.

Biesterfeld foresees its new rubber filler being used in products such as footwear, where consumers are becoming sustainability conscious.

"There was a lot of interest in Oysterlean and quite a few customers asked for more details or even samples," said Henning.

Many companies in the rubber sector, he noted, are opening new lines of research into "green products" as sustainable alternatives to conventional products with a higher carbon footprint.