Calorimetric Study of Graphene Oxide Thermal Stability
Pritishma Lakhe (1), Devon Kulhanek (2), Wanmei Sun (2), Bin Zhang (1), Micah J. Green (2) and M. Sam Mannan (1)
1. Mary Kay O’Connor Process Safety Center, Artie McFerrin Department of Chemical Engineering, Texas A&M University System, College Station, TX 77843, USA
2. Artie McFerrin Department of Chemical Engineering, Texas A&M Engineering Experiment Station, College Station, TX 77843, USA
Large-scale production of graphene is of increasing commercial and academic interest because graphene has shown immense potential in energy storage and composite filler applications. Synthesis routes that involve graphene oxide (GO) are predominantly used because this method has shown potential for bulk production at high yield. This method involves the oxidation of graphite to GO and its subsequent reduction to reduced graphene oxide (rGO). However, prior studies have shown that GO can undergo explosive decomposition under certain conditions. There is no documented process safety incident related to GO so far, but GO is an energetic material that can undergo explosive thermal reduction. The motivation of this research is to investigate potential process safety issues with bulk GO storage and handling because the industry is ramping up large-scale manufacturing of GO. Our data shows increasing GO mass decreases the temperature at which material decomposes. We quantified the pressure release rate and pressure generation during decomposition. We also discussed the underlying causes of the explosive behavior of bulk GO and proposed safer storage and handling conditions. Studies were conducted in Advanced Reactive System Screen Tool (ARSST). We compared the GO decomposition made in lab using modified Hummers method to the commercially available GO. Finally, we used the Frank Kamenetskii model to obtain the critical density and mass necessary for GO decomposition. This research will be beneficial in assessing the hazards of GO and enhancing the safety of rGO production processes over their life cycles.
Keywords: Bulk graphene oxide, Calorimetric, Energetic material, Thermal hazard, Nanomaterials