These fluoroelastomer gaskets are 100% compatible with Biodiesel. Use them to seal the flanges on our 6" diameter dry wash towers. Using these gaskets is essential for biodiesel dry wash applications. If regular rubber were to be used, the gaskets would need to be replaced regularly on each change due to corrosion from the biodiesel. The fluoroelastomer gaskets never corrode and will last the lifetime of the tower.