Estimation of life cycle greenhouse gas emissions of asphaltene-based carbon fibers derived from oil sands bitumen

Abstract

Bitumen-derived asphaltenes have emerged as a potential precursor for carbon fiber production. The technology to make it possible is in the early stages of research and development and so there are no studies on the GHG emissions from the process, which are critical to compare its carbon footprint with that of polyacrylonitrile (PAN), the standard precursor for carbon fiber production. The asphaltene-based carbon fiber (ACF) life cycle stages are bitumen production, asphaltene separation, precursor manufacturing, and carbon fiber production. In this study, we developed data-intensive models to estimate the life cycle GHG emissions of ACF. Sensitivity and uncertainty analyses were also performed to determine the inputs that have the largest effect on the GHG emissions of ACF. The results show that the life cycle GHG emissions of ACF are 16.2 kg CO2eq/kg CF. This value represents a reduction of 68.7% compared to PAN-based carbon fiber. The carbon fiber production stage is the most emission-intensive, mainly because of the high consumption of electricity. When uncertainty is considered, the life cycle GHG emissions of ACF range from 10.4 to 21.8 kg CO2eq/kg CF. The outcome of this study confirms the potential of asphaltenes as a low-carbon intense raw material for carbon fiber production.