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AbstractThis research addresses the growing need for fast and cost-efficient methods for microplastic (MP) analysis. We present a thermo-analytical method that enables the identification and quantification of different polymer types in sediment and sand composite samples based on their phase transition behavior. Differential scanning calorimetry (DSC) was performed, and the results were evaluated by using different regression models. The melting and crystallization enthalpies or the change in heat capacity at the glass transition point were measured as regression analysis data. Ten milligrams of sea sand was spiked with 0.05 to 1.5 mg of microplastic particles (size: 100 to 200 µm) of the semi-crystalline polymers LD-PE, HD-PE, PP, PA6, and PET, and the amorphous polymers PS and PVC. The results showed that a two-factorial regression enabled the unambiguous identification and robust quantification of different polymer types. The limits of quantification were 0.13 to 0.33 mg and 0.40 to 1.84 mg per measurement for semi-crystalline and amorphous polymers, respectively. Moreover, DSC is robust with regard to natural organic matrices and allows the fast and non-destructive analysis of microplastic within the analytical limits. Hence, DSC could expand the range of analytical methods for microplastics and compete with perturbation-prone chemical analyses such as thermal extraction–desorption gas chromatography–mass spectrometry or spectroscopic methods. Further work should focus on potential changes in phase transition behavior in more complex matrices and the application of DSC for MP analysis in environmental samples.

This study presents a methodology to determine the specific heat capacity (Cp) of materials for thermal energy storage (TES) by DSC. These materials have great energy storage capacities, and due to that, important heat flow fluctuations can be observed for each temperature differential, taking more time to reach a desired temperature gradient. Three different DSC methods are considered to be applied in the methodology, and are explained and compared in this study in order to select the most proper one for Cp determination. To perform this study, the Cp of three materials commonly used in sensible TES systems, slate, water, and potassium nitrate (KNO3), is determined. Excellent results with errors lower than 3% are obtained when using the proposed methodology with the areas method. Worse results are obtained with both dynamic and isostep methods, with errors up to 6% and 16% respectively, as a consequence of sensitivity problems during the measurements. ; The work is partially funded by the Spanish government (ENE2015-64117-C5-1-R (MINECO/FEDER)). The authors would like to thank the Catalan Government for the quality accreditation given to their research groups GREA (2014 SGR 123) and research group DIOPMA (2014 SGR 1543). The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement n° PIRSES-GA-2013-610692 (INNOSTORAGE) and from the European Union's Horizon 2020 research and innovation programme under grant agreement No 657466 (INPATH-TES). Dr. Camila Barreneche would like to thank Ministerio de Economia y Competitividad de España for Grant Juan de la Cierva, FJCI-2014-22886.

In general, PCM are classified in organic and inorganic groups or families. First group mainly encloses paraffin, fatty acids, and sugar alcohols. Inorganic are mostly represented by salt hydrates, salt solutions, and metals. Eutectics and mixtures are also being formulated to obtain a desired phase change temperature. One of the most important PCM requirements is being stable after a number of repeated melting/freezing cycles, which is known as cycling stability. A PCM should present the same or almost the same thermal, chemical and physical properties after a repeated number of freezing and melting cycles. Thermal cycling tests results and detailed tests procedures are classified by PCM type in this review. Moreover, the parameters that must be considered in order to perform cycling stability tests are highlighted depending on the importance they have on the following four issues: the choice of the equipment to perform the cycling tests; the selection of the techniques to characterize the PCM before and after thermal cycling test and to follow the PCM thermal degradation; the definition of the number of cycles to perform; and finally, the choice of the heating rate and thermal cycling method (pyramid, or dynamic, or others) to perform the tests. It is mandatory to conclude that, based on the literature reviewed, no common standard for thermal cycling stability tests is available at the moment. ; The research leading to these results has received funding from the European Commission Seventh Framework Programme (FP/ 2007-2013) under grant agreement No. PIRSES-GA-2013-610692 (INNOSTORAGE). Furthermore, the work is partially funded by the Spanish government (ENE2011-28269-C03-02 and ENE2011- 22722). The authors would like to thank the Catalan Government for the quality accreditation given to their research groups GREA (2014 SGR 123) and DIOPMA (2014 SGR 1543). Aran Solé would like to thank the Departament d'Universitats, Recerca i Societat de la Informació de la Generalitat de Catalunya for her research fellowship.

Thermochemical materials (TCM) are proposed for thermal energy storage as one of the future options to achieve lower energy consumption in buildings and other industrial applications, as well as to store energy from solar energy. In this study, the thermophysical properties of two TCM, CaCl2 and zeolite, are determined with TGA and DSC and samples are cycled 4 times with TGA. Results show that the material with the highest energy density is the salt, CaCl2. Moreover, both materials under study present noble cyclability. ; The work is partially funded by the Spanish government (ENE2011-28269-C03-02 and ENE2011-22722). The authors would like to thank the Catalan Government for the quality accreditation given to their research group GREA (2009 SGR 534) and research group DIOPMA (2009 SGR 645). Furthermore, the work was partially funded by European Union (Cost Action TU0802).

At this moment, the global energy consumption in buildings is around 40% of the total energy consumption in developed countries. Thermal energy storage (TES) is presented as one way to address this energyrelated problem proposing an alternative to reduce the gap between energy supply and energy demand. One way to store energy is using thermochemical materials (TCM). These types of materials allow accumulating energy through a chemical process at low temperature, almost without heat losses. In addition, it is a stable way to perform the heat storage and TCM can be implemented for seasonal storage or/and long term storage. This study compares the cyclability, from the thermophysical point of view, CaCl2 which follows a chemical reaction and zeolite which follows a sorption process to be used as TCM for seasonal/long term storage. The main results show that the chemical reaction TCM is more energy-efficient than the sorption TCM. The CaCl2 calculated energy density is 1.47 GJ/m3 , being the best option to be considered to be used as TCM, even though the dehydration process of the zeolite is simpler and it occurs at higher temperatures its calculated energy density is only 0.2 GJ/m3 . ; The research leading to these results has received funding from the European Commission Seventh Framework Programme (FP/ 2007-2013) under grant agreement No ENER/FP7/1295983 (MERITS) and under grant agreement no. PIRSES-GA-2013-610692 (INNOSTORAGE). Furthermore, the work is partially funded by the Spanish government (ENE2011-28269-C03-02 and ENE2011- 22722), and the European Union by Cost Action TU0802. The authors would like to thank the Catalan Government for the quality accreditation given to their research groups GREA (2014 SGR 123) and DIOPMA (2014 SGR 1543).

Apple pomace was studied as a possible raw material for biobutanol production. Five different soft physicochemical pretreatments (autohydrolysis, acids, alkalis, organic solvents and surfactants) were compared. The pretreated biomass was subsequently subjected to a conventional enzymatic treatment to complete the hydrolysis. One of the hydrolysates was readily fermented by Clostridium beijerinckii CECT 508 in 96 h (3.55 g/L acetone, 9.11 g/L butanol, 0.26 g/L ethanol; 0.276 gB/gS yield; 91% sugar consumption). Therefore, it is possible to optimise pretreatment conditions of lignocellulosic apple pomace to reduce inhibitor concentrations in the final hydrolysate and perform successful ABE fermentations without the need of a detoxification stage. ; This document is a pre-print version of the manuscript that was subsequently peer-reviewed and accepted for publication by the journal Applied Microbiology and Biotechnology (Vol. 101, pages 8041-8052, year 2017). The final publication is available at Springer via http://dx.doi.org/10.1007/s00253-017-8522-z. The present work has been performed as part of the H2020-LCE-2015 Waste2Fuels project (Sustainable production of next generation biofuels from waste streams - Waste2Fuels; GA - 654623), funded by the European Union's Horizon 2020 Research and Innovation Programme. MH-V is supported by a postdoctoral contract (DOC-INIA, grant number DOC 2013-010) funded by the Spanish Agricultural and Agrifood Research Institute (INIA) and the European Social Fund. The authors thank Novozymes for kindly providing samples of their enzymes. Authors thank R. Antón del Río, N. del Castillo Ferreras and G. Sarmiento Martínez for their technical help.

The implementation of organic phase change materials (PCMs) in several applications such as heating and cooling or building comfort is an important target in thermal energy storage (TES). However, one of the major drawbacks of organic PCMs implementation is flammability. The addition of flame retardants to PCMs or shape-stabilized PCMs is one of the approaches to address this problem and improve their final deployment in the building material sector. In this study, the most common organic PCM, Paraffin RT-21, and fatty acids mixtures of capric acid (CA), myristic acid (MA), and palmitic acid (PA) in bulk, were tested to improve their fire reaction. Several flame retardants, such as ammonium phosphate, melamine phosphate, hydromagnesite, magnesium hydroxide, and aluminum hydroxide, were tested. The properties of the improved PCM with flame retardants were characterized by thermogravimetric analyses (TGA), the dripping test, and differential scanning calorimetry (DSC). The results for the dripping test show that fire retardancy was considerably enhanced by the addition of hydromagnesite (50 wt %) and magnesium hydroxide (50 wt %) in fatty acids mixtures. This will help the final implementation of these enhanced PCMs in building sector. The influence of the addition of flame retardants on the melting enthalpy and temperatures of PCMs has been evaluated. ; The research leading to these results has received funding from the European Commission Seventh Framework Programme (FP/2007-2013) under grant agreement number PIRSES-GA-2013-610692 (INNOSTORAGE) and from the European Union's Horizon 2020 research and innovation program under grant agreement No. 657466 (INPATH-TES). The authors would like to thank the Catalan Government for the quality accreditation given to their research groups GREA (2014 SGR 123), DIOPMA (2014 SGR 1543) and GICITED (2014 SGR 1298), and also the MINECO for the project BIA2014-52688-R, ENE2015-64117-C5-1-R, ENE2015-64117-C5-2-R, and ENE2015-64117-C5-3-R. Alvaro de Gracia and Camila Barreneche would like to thank Ministerio de Economia y Competitividad de España for Grant Juan de la Cierva, FJCI-2014-19940 and FJCI-2014-22886, respectively.

Plastics have different thermal stability, depending on the structure of the polymer chains. It is therefore very important to know their thermal properties, which influence the temperature regime of processing equipment. This paper presents examples of differential scanning analysis (DSC) and thermogravimetry analysis (TG) of selected plastics in an Ar protective atmosphere and also in an oxidative atmosphere of static air. These analyses can be used for proposing a welding temperature regime.

Abstract The 2,4,6-triamino-1,3,5-trinitrobenzene (TATB) is perhaps the most thermostable and insensitive explosive known. Its low sensibility to shock makes it suitable for military and civil applications. TATB application is done either alone or in combination with another high energetic material. This study aimed at reporting the review about many processes to produce TATB and the problems associated with them, as well as suggest techniques like Fourier Transform Infrared Spectroscopy (FT-IR) and Differential Scanning Calorimetry (DSC), which can be useful in the characterization of this energetic compound.

Ionic liquids (diimidazol-1-ium esters) prepared from wastes, crude glycerol and carboxylic acids are investigated as potential phase change materials (PCM). The ionic liquids (IL) with best thermophysical properties were those with also better production yield (higher than 75%). The chemical composition of those IL was with R1 being (CH3)3CCO, CH3(CH2)14CO or C2H3CO; R2 being BIM+; R3 being BIM+; and X- being 2 Cl‾. Phase change of state (solid-liquid) of this IL was 85 ºC, 264 ºC and 128 ºC, which means potential application in different fields such as domestic hot water, solar cooling and industry, respectively. The measured melting enthalpy 328 kJ/kg, 408 kJ/kg, and 660 kJ/kg is much higher in all cases than the usual found in commercial PCM (100 kJ/kg), therefore, these ILs synthetized in this study are proper candidates to be used as PCM because of the huge amounts of energy that they are able to store and their low cost. Moreover, biobPCM are sustainable materials since its obtaining process is based on oil. ; The work is partially funded by the Spanish government (ENE2015-64117-C5-1-R (MINECO/FEDER) and CTQ2015-70982-C3-1-R (MINECO/FEDER)). The authors would like to thank the Catalan Government for the quality accreditation given to the research groups GREA (2014 SGR 123), Agricultural Biotechnology (2014 SGR 1296) and DIOPMA (2014 SGR 1543). Dr. Camila Barreneche would like to thank Ministerio de Economia y Competitividad de España for Grant Juan de la Cierva, FJCI-2014-22886.The research leading to these results has received funding from the European Union's Seventh Framework Program (FP7/2007–2013) under grant agreement n° PIRSES-GA-2013-610692 (INNOSTORAGE) and from the European Union's Horizon 2020 research and innovation program under grant agreement No 657466 (INPATH-TES).

"Solid-state thymol, liquid carvacrol and eugenol were characterized by using combustion calorimetry and thermal analysis-simultaneous thermogravimetry (TG) coupled with differential scanning calorimetry (DSC) techniques. The enthalpies of formation were calculated using the measured heat of combustion for the studied compounds. Our values were compared with the literature and calculated data. Information about the stability of the samples was reported. From DSC measurements, the temperatures of melting-decomposition and their corresponding enthalpies were calculated. "