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This work describes the composition of the products from solvolysis of thermoset polyester in an acetone/water mixture. A qualitative and quantitative evaluation of the compositions of the aqueous and oil phases was achieved by the combination of liquid chromatography with electrospray ionization mass spectrometry (LC-ESI-MS/MS), gel permeation chromatography (GPC), and total organic carbon (TOC). Close to 100% of the organic carbon in the aqueous phase was explained by the monomers phthalic acid and dipropylene glycol, co-solvent acetone, and a secondary reaction product, isophorone. In the oil, the most abundant compounds were isophorone, 3,3,6,8-tetramethyl-1-tetralone, and dihydroisophorone. While the first two compounds were intermediates in the self-condensation of acetone, dihydroisophorone has not been reported previously as the by-product of the conventional acetone self-condensation reaction pathway. The quantification results have shown that solvolysis can be successfully used to close the loop in the polymer life cycle while producing a broad spectrum of high-value products that could be recycled for production of polymers, used as a building blocks, or as fine chemicals. [ABSTRACT FROM AUTHOR]

In this study, spectroscopy and image analysis have been employed to characterize the difference between pure strains of Clostridium tyrobutyricum and the strains adapted to salinity and temperature for microbial enhanced oil recovery purposes. The pure strain and adapted bacteria strains have been metabolically characterized by gas production, pH and morphologically by FT-IR spectroscopy and image analysis. The result of FT-IR analysis was able to distinguish the adapted strains from the pure strain based on cell content. Further results from multivariate data analysis using PCA method showed that the morphological and physiological changes were induced with increasing salt concentration that correlates with gas production and change in pH. It was found that the adaptation probably occurred due to the formation of bacterial clusters at extremely high salinity. High density of bacteria cells occurring as single cells and rod like shape were found in low to medium salinity in contrast to high salinity where the proportion of bacteria cells were found in clusters, round shaped but with decreasing cell density. The shifts in the morphological as well as the physiological composition of the bacterial assemblage in the media allow for a clear subdivision into different salinity groups. [ABSTRACT FROM AUTHOR]

In recent years, geothermal energy use from low-temperature sandstone reservoirs has sharply increased. Nonetheless, the injection of heat-depleted geothermal fluids has not been an easy task because of well/formation damage and operational/economic issues. Sønderborg geothermal plant is a case example of heat-mining from a low-temperature reservoir. It is in the northeast of Sønderborg towards Augustenborg Fjord. The present work takes into consideration the regional and local geology of the Sønderborg area, construction of the wells, field experience and water chemistry. The main issues of the geothermal plant appear to be related to the construction of the wells and reinjection of the heat-depleted brine. Our water chemistry analysis and PHREEQC simulations indicate that geothermal brine was saturated with respect to carbonate and barite minerals. The excess of Ca2+ and SO42− ions could have led to the formation and precipitation of carbonate and sulfate scales. Moreover, the increment of iron concentration over time could suggest the ingress of oxygen and pitting corrosion due to the presence of halide ions. [ABSTRACT FROM AUTHOR]

Abstract: In the present work the influence of the OH groups on the photocatalytic activity and the photoinduced hydrophilicity of microwave assisted sol–gel TiO2 films was investigated. The prepared TiO2 films were characterized using XRD and AFM. Furthermore, the surface of the TiO2 films was examined by help of XPS in order to determine the amount of OH groups before and after UV irradiation at different humidities. The activity of the TiO2 films was determined using stearic acid as a model compound and the photoinduced superhydrophilicity was investigated through contact angle measurements. The results of this investigation showed that the microwave assisted sol–gel technique produces highly homogeneous and efficient TiO2 films without the need for heat treatment for crystallization. Based on the conducted experiments it is suggested that the amount of OH groups on the TiO2 surface highly influence the photocatalytic activity and the photoinduced superhydrophilicity and that the two mechanisms may be closely related. It is suggested that the superhydrophilicity is obtained through a combination of photocatalytic degradation of organic contaminants and surface structural changes in form of an increased amount of OH-groups. [Copyright &y& Elsevier]