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The preparation of high-value biochar as a supercapacitor is a promising way for biomass utilization. In this work, a self-activation method was proposed to prepare nitrogen and sulfur co-doping hierarchical porous biochar by using mantis shrimp shell as carbon, nitrogen, and sulfur precursors. The porosity and surface chemical properties of biochar were adjusted upon different temperatures. It was found that the obtained biochar had a dendritic and uniform morphology, in which micro-, meso-, and macropores were interconnected regularly in the structure, and the nitrogen and sulfur heteroatoms were successfully homogeneously introduced into the carbon frameworks. On the basis of electrochemical tests, novel shell biochar with an activation temperature of 750 °C demonstrated the highest specific capacitance, which was 201 F g −1 at a current density of 1 A g −1 in a 6 M KOH electrolyte, due to the large BET surface area of 401 m 2 g −1 , and high nitrogen (8.2 wt %) and sulfur content (1.16 wt %). The in situ template approach from natural biomass provided tremendous potential for the active electrode materials of supercapacitors.

Carbon fiber laminate composites have been utilized in the aerospace industry by replacing lightweight aluminum alloy components in the design of aircraft. By replacing low flammability aluminum components by carbon fiber laminates, the potential fuel load for aircraft fires may be increased significantly. A pyrolysis model has been developed for a Toray Co. carbon fiber laminate composite. Development of this model is intended to improve the understanding of the fire response and flammability characteristics of the composite, which complies with Boeing Material Specification 8–276. The work presented here details a methodology used to characterize the composite. The mean error between the predicted curves and the mean experimental mass loss rate curves collected in bench-scale gasification tests was calculated as approximately 17% on average for heat fluxes ranging from 40 to 80 kW m−2. During construction of the model, additional complicating phenomena were investigated. It was shown that the thermal conductivity in the plane of the composite was approximately 15 times larger than the in-depth thermal conductivity, the mass transport was inhibited due to the high density of the laminae in the composite, and oxidation did not appear to significantly affect pyrolysis at heat fluxes up to 60 kW m−2.

A methodology for parameterization of kinetics and thermodynamics of decomposition of polymeric materials has been extended to blends of a polymer with condensed-phase active flame retardants. This methodology is based on Thermogravimetric Analysis, Differential Scanning Calorimetry, Microscale Combustion Calorimetry and inverse numerical modeling of these experiments. Material systems consisting of poly(lactic acid), melamine and ammonium polyphosphate were used to demonstrate this parameterization process. The resulting model consists of a set of first and second order (two component) reactions that define the rate of gaseous pyrolyzate production, heats of these reactions, heat capacities of the condensed-phase reactants and products and heats of combustion of the components of the gaseous pyrolyzate. This model is shown to reproduce results of all aforementioned experiments with a high degree of detail and predict relation between the outcome of these experiments and material composition. It is expected that a combination of this model with thermal transport parameters, which determination will be a subject of separate study, will yield a complete pyrolysis model capable of predicting the dynamics of burning and flame spread on these materials and dependence of this dynamics on the flame retardant content.

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