Can carbon nanomaterials help avoiding resource scarcity?
Poster (konferens), 2015
The pressure on resource extraction is increasing due to a continued growth of world population and affluence. In particular, scarcity may become a pressing problem for several metals in the coming decades (Ljunggren Söderman et al. 2014). Carbon nanomaterials, such as fullerenes, carbon nanotubes, graphene and nanocellulose, have been suggested as a potential remedy for this. They have gained high interest in recent years, owing to their unique properties, which potentially could make them viable substitutes for a range of scarce and critical metals. However, carbon nanomaterials also require raw materials in order to be produced. Having carbon as main constituent, carbon nanomaterials require carbon feedstock of either renewable or fossil origin. Although carbon is an abundant element, not all chemical forms of carbon can be used directly for carbon nanomaterial production. The first aim of this study is to list potential raw materials for the carbon nanomaterials fullerenes, carbon nanotubes, graphene and nanocellulose. Second, raw material reserves available for future potential production rates of carbon nanomaterials are assessed. This analysis is done using prospective material flow analysis (MFA), which is a forward-looking type of MFA in contrast to the more traditional MFA that typically considers current material flows. Third, we outline which scarce materials that may be replaced by carbon nanomaterials in these applications. With this method, resource benefits from substitution and resource constraints of carbon nanomaterials can be assessed, both in the short and long term. Preliminary results show that the carbon nanomaterials investigated have the potential to replace a number of scarce materials. For example, graphene could replace indium and tin in transparent screens (Segal 2009). There may also be short term resource constraints for carbon nanomaterials. For example, graphene is currently suggested to be produced from graphite for some applications, and graphite has been listed as a critical material. We also discuss risks of competition over carbon feedstock (fossil and biomass) between current uses of carbon feedstock (e.g. plastics and wood) and carbon nanomaterials.