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Resumen del póster presentado en Symposium on Renewable Energy and Products from Biomass and Waste, CIUDEN (Cubillos de Sil, León, Spain), 12-13 May 2015 Electronic waste is one of the fastest growing waste streams in the world due to the rapid pace of technology enhancement and development. The exponential growth of electronic waste contributes to a rapid increase in the rate of contaminants and waste entering landfills. This fact implies the need for an appropriate management of waste electrical and electronic equipment (WEEE). Printed circuit boards (PCB) are one of the most complex constituents of WEEE, with a mixture of both valuable and/or hazardous elements. Thermal treatments represent an interesting alternative to recycle this kind of waste, but particular attention has to be paid to the potential emissions of toxic by-products. In this study, the emissions from thermal degradation of printed circuit boards (with and without metals) have been studied using a laboratory scale reactor, under oxidizing and inert atmosphere at 600 and 850 oC. The study comprises the analysis of gases, halogens and hydrogen halides, carbon oxides, light hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), chlorinated phenol, chlorinated benzenes and brominated phenols, among other semivolatile compounds, as well as polybromo- and polychloro- dibenzo-p-dioxins and furans and dioxin-like polychlorobiphenyls. The maximum formation of PAHs was found in pyrolysis at 850 oC, naphthalene being the most abundant. High levels of 2-, 4-, 2,4-, 2,6- and 2,4,6-bromophenols were found, especially at 600 oC. Emissions of PCDD/Fs and dioxin-like PCBs were very slow and much lower than that of PBDD/Fs, due to the higher bromine content of the samples. Combustion at 600 oC was the run with the highest PBDD/F formation: the total content of eleven 2,3,7,8-substituted congeners (tetra- through heptaBDD/Fs) was 7240 and 3250 ng WHO2005-TEQ/kg sample, corresponding to the sample with and without metals, respectively. Ministry of Economy and Competitiveness (Spain): CTQ2013-41006-R. Valencian Community Government (Spain): PROMETEOII/2014/007

The permanent expansion of the market of electrical and electronic equipment (EEE) and the shorter innovation cycles, lead to a faster replacement of these appliances, making EEE a fast-growing source of waste (WEEE). As stated in Directive 2012/19/EU1 on waste electrical and electronic equipment, the content of hazardous components in EEE is a major concern during the waste management phase, and recycling of WEEE is not currently undertaken to a sufficient extent, resulting in a loss of valuable resources. Support for this work was provided by: Ministry of Education and Science (Spain) (CTQ2008-05520 project); Valencian Community Government (Spain) (PROMETEO/2009/043/FEDER project).

Paper submitted to the 7th International Symposium on Feedstock Recycling of Polymeric Materials (7th ISFR 2013), New Delhi, India, 23-26 October 2013. A comparison between different emission rates of various pollutants obtained from various wastes is presented. The studied wastes were the following: polyethylene, tyres, sewage sludge, polyvinyl chloride, cotton textiles, polyester textiles, meat and bone meals, varnish wastes, olive oil solid waste (pomace), waste lube oils, paper waste, tomato plant, pine needles and cones, mobile phones and automotive shredder residue. The decomposition of these wastes was studied in a horizontal laboratory scale reactor at 850 ºC in an inert and an oxidizing atmosphere, and the analysis of the pollutants evolved comprised several compounds such as light hydrocarbons, PAHs and PCDD/Fs. Ministry of Education and Science (Spain) (CTQ2008-05520 project) and Valencian Community Government (Spain) (PROMETEO/2009/043/FEDER project).

Paper submitted to the 7th International Symposium on Feedstock Recycling of Polymeric Materials (7th ISFR 2013), New Delhi, India, 23-26 October 2013. In this contribution we present the results of the research done at the University of Alicante in the last four years [1-7] about the thermal decomposition of waste electrical and electronic equipment (WEEE). Several materials have been studied, including PVC and halogen-free wires, printed circuit boards and casing from mobile phones, as well as brominated flame reatardants used in the EEE preparation such as TBBPA (tetra-bromo-bisphenol-A). Several experiments were performed in a nitrogen atmosphere (pyrolysis runs) and also in an oxidative atmosphere with different oxygen concentrations. Thermogravimetric runs were used to characterize samples, and a horizontal laboratory reactor was used to study the formation and destruction of pollutants during the thermal decomposition of these samples. More than 150 compounds, including carbon oxides, light hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), chlorophenols (ClPhs), chlorobenzenes (ClBzs) and bromophenols (BrPhs) have been identified and quantified. Furthermore, polychlorodibenzo-p-dioxin and polychlorodibenzofurans (PCDD/Fs), polybromodibenzo-p-dioxin and polybromodibenzofurans (PBDD/Fs), and dioxin-like PCBs produced were analyzed. Generalitat Valenciana: PROMETEO/2009/043/FEDER. Ministerio de Educación y Ciencia: CTQ2008-05520.

Paper submitted to the 7th International Symposium on Feedstock Recycling of Polymeric Materials (7th ISFR 2013), New Delhi, India, 23-26 October 2013. A kinetic study has been carried out by thermogravimetry in order to compare the thermal behavior of printed circuit boards of mobile phones before and after the removal of the metallic fraction. Experiments were performed in nitrogen atmosphere (pyrolysis runs) as well as in an oxidative atmosphere (10% and 20% oxygen in nitrogen). Several dynamic and dynamic + isothermal runs have been carried out at different heating rates (5, 10 and 20 K min−1), from room temperature to more than 900 K. Moreover, TG–MS experiments were performed (in inert and oxidizing atmosphere) in order to better understand the thermal decomposition of these wastes. Different reaction models are proposed, one for pyrolysis and one for combustion of the two kinds of wastes studied, which proved to simulate appropriately the experimental results at all the heating rates simultaneously. Regarding the analysis of pollutants evolved, pyrolysis and combustion runs have been carried out at 600 ºC and 850 ºC in a horizontal laboratory furnace in order to analyze a wide range of gases, hydrogen halides, carbon oxides, light hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), chlorinated phenols (ClPhs), chlorinated benzenes (ClBzs) and brominated phenols (BrPhs), among others. Furthermore, polybromo- and polychloro-dibenzo-p-dioxins and furans (PBDD/Fs and PCDD/Fs) and dioxin-like polychlorobiphenyls (PCBs) are being analyzed. Ministry of Education and Science (Spain) (CTQ2008-05520 project) and Valencian Community Government (Spain) (PROMETEO/2009/043/FEDER project).

Paper submitted to the 31st International Symposium on Halogenated Persistent Organic Compounds (Dioxin 2011), Brussels, Belgium, 21-25 August 2011. Brominated compounds are widely used as flame retardants in industrial operations. Due to their high efficiency, compatibility and small influence on mechanical properties, brominated flame retardants (BFRs) have a broad application area, mainly in the field of polymeric materials. Tetrabromobisphenol A (TBBPA) is the most important BFR, representing around 60 % of BFR total production. The estimated global consumption of TBBPA was around 170000 metric tons for 2004. The authors thank the research project CTQ2008-05520 from the Spanish Ministry of Education and Science and research projects ACOMP2011/224 and PROMETEO/2009/043/FEDER from the Valencian Community Government (Spain) for the support provided.