Biomass fuels represent a renewable energy source, they are CO 2 neutral fuels, and their use reduces the consumption of fossil fuels and limits the emissions of SO x , NO x , and heavy metals. They are used in pyrolysis, gasification, combustion, and co-combustion. The devolatilization is a fundamental mechanism in all these processes, especially for high volatile matter fuels. In this work, the devolatilization of biomass fuels (of different origin, properties, and composition) and biomass components is studied coupling thermogravimetric (TG) analysis with infrared spectroscopy. The characteristic temperatures are determined for the main devolatilization steps and compared for all fuels. A bituminous coal and a paper sludge are also studied for comparison. Light gases released (CO, CO 2 , H 2 O, CH 4 , CH 3 OH, HCOOH) are detected, whereas more complex organic (hydrocarbon and oxygenated) compounds are grouped because of the large variety of volatile species released in a narrow range of temperature. The weight loss of biomass fuels is related to their chemical composition (i.e., considering the devolatilization behavior of cellulose, hemicellulose (xylan), and lignin in the same operating conditions). The aim of the work is to apply a summative law for the TG results (validated in previous experimental and literature works) to obtain the chemical composition of biomass fuels and to validate and extend a summative law for the FTIR profiles of volatile species released. Calculated values obtained using this method are in good agreement with the experimental results. Therefore, the validation of this correlation allows the prediction of the devolatilization of biomass fuels considering the initial chemical composition. This is useful for practical applications, plant designing, handling, and modeling.

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The thermal stability and decomposition products of hexabromocyclododecane (HBCD), a widely used aliphatic brominated flame retardant, were investigated. HBCD thermal degradation was carried out in nitrogen and in air at moderate heating rates (10 °C/min) using thermogravimetric analyzers and a laboratory-scale fixed-bed reactor. The identification of decomposition products was based mainly on FTIR and gas-chromatographic/mass-spectrometric techniques. Quantitative data on hydrogen bromide formation and on the bromine distribution among the different product fractions were obtained. For the experimental conditions used in this study, about 75 wt % of the bromine is released as HBr, and 25 wt % is involved in the formation of high-molecular-weight bromo-organic compounds. The main pathways of HBCD thermal degradation were assessed, and a global mechanism for HBCD decomposition was proposed.

This study focused on the investigation of the thermal degradation process of tetrabromobisphenol A (TBBA). The use of combined experimental techniques allowed the quantitative characterization of TBBA decomposition products and the analysis of the thermal degradation rates. The distribution of bromine among the different decomposition product fractions was investigated. In the open configuration used for the experiments, hydrogen bromide, brominated bisphenol A species, and brominated phenols resulted in the main decomposition products. Bromine was mainly evolved as hydrogen bromide, although a relevant quantity resulted present in the primary high molecular weight condensable product fraction, in agreement with the decomposition pathways proposed. The results evidenced that accidents involving TBBA thermal degradation, such as fire or process runaways, may pose relevant safety problems because of the possible release of considerable quantities of hazardous decomposition products.