A Study of Carbonized Lignin as an Alternative to Carbon Black

The production of biobased carbonaceous powder from bioethanol coproduct lignin for use as a substitute for fossil fuel-derived conductive carbon black filler is examined. The synthesis procedure used for the formation of biobased carbon black is studied in order to obtain properties similar to conventional carbon black. Characterization of the carbon material after varying carbonization temperatures and ball milling times was investigated to optimize carbon size, surface area, and thermal and electrical conductivity. The optimized carbonized ball milled lignin had a carbon content greater than 90% with the majority of the carbon atoms in the sp(2) hybridized state. The carbonized ball milled lignin exhibited a surface area 882% larger and a thermal conductivity 36% greater in comparison to the conductive carbon black tested, while the electrical conductivity was 9.5 S m(-1) lower for the carbonized ball milled lignin. This research has demonstrated the possibility of producing biobased carbon black as a potential substitute for commercial carbon black by using lignin as a precursor material.