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Sewage sludge-based porous materials were prepared through an integrated and energy-saving procedure that combines chemical activation with an alkali (NaOH or K2CO3) and physical activation with CO2 in a single step. The study was conducted in a wide temperature range (600–1000 °C), using higher temperatures than those commonly used. From the standpoint of textural properties, the impregnation results in a decrease in the optimum activation temperature: 800 °C for untreated samples, and 600–700 °C for impregnated samples. The impregnation increases the amount of –OH and –NH functional groups, and it also leads to the generation of new oxygen- and/or nitrogen-containing functionalities (above 800 °C for the impregnation with K2CO3 and in the whole temperature range for the impregnation with NaOH). The chemical treatment favors the development of magnetic properties on biochars, which is an advantage for its reuse in wastewater treatment, since it favors the removal of anionic surfactants and heavy metals such as lead, copper, zinc, and manganese. The uptake of phenol and methylene blue (MB) is maximized with the combination of the impregnation (with NaOH for phenol and K2CO3 for MB) and the use of a moderate temperature (600–700 °C). The optimum uptake values represent an increase of 87% and 152% for MB and phenol, respectively, compared to the highest value of non-impregnated samples (activated at 800 °C), with the advantage of the lower temperature required. [ABSTRACT FROM AUTHOR]

The aim of the present study was to analyze differences in the emotional processing (valence, arousal, and dominance) of food-related information in patients with eating disorders (ED), patients with obesity, and healthy women. Moreover, the mediator role of negative affect and the moderating role of the diagnostic group (ED vs. non-ED) were analyzed. Method: The sample consisted of 94 women (39 with eating disorders, 19 with obesity, and 36 healthy participants). Measures: International Affective Picture System (IAPS) food picture exposure task; Self-Assessment Manikin Analog-Visual Scale (SAM) appraising Arousal, Valence, and Dominance; Eating Attitudes Test (EAT-26); Positive and Negative Affect Schedule (PANAS). Results: Patients with purging symptomatology rated food images as more unpleasant than healthy women. Patients with purging and restrictive eating symptomatology showed higher levels of arousal and less dominance over the emotions experienced, compared to patients with obesity and healthy women. The mediation analysis showed that negative affect mediated the relationship between eating symptomatology (EAT-26) and the Valence of food images, as well as the control over the emotions experienced when viewing food images (Dominance). For the moderation analysis participants were regrouped into two groups (ED patients vs. non-ED patients). The direct relationship between eating symptomatology and food image valence was moderated by the diagnostic group. However, the group did not moderate the direct relationship between the EAT-26 and dominance over experienced emotions, or the indirect effect on eating symptomatology through negative affect. These results show the relevance of negative affect in the emotional processing of food-related information, and they support an eating disorder-disordered eating dimensional perspective. [ABSTRACT FROM AUTHOR]

The article presents the discussion on relationship between the emotional state of HCW and environmental variables. Topics include leading to significant concern among HCW precipitating emotional responses of anxiety, depression, and acute stress; and finding significant differences between physicians and other health professionals in all clinical symptoms.

The study has focused on the regenerability of the CuO-ZnO-MnO/SAPO-18 (CZMn/S) bifunctional catalyst used in the direct synthesis of dimethyl ether (STD process) from H + CO + CO feeds. The runs have been conducted in a fixed bed reactor under the following conditions: 250-300 °C; 10-40 bar; 1.25-10.18 g h mol; time on stream, 5-30 h; CO/CO molar ratio, 0-1; feeding H + CO + CO with a H/CO molar ratio of 3. Coke deposition has been determined as the main deactivation cause, and both the measurement of the coke content and the identification of three types of coke have been carried out by means of temperature programmed oxidation analyses. Reaction-regeneration cycle runs have been carried out in a fixed bed isothermal reactor, concluding that it is possible to regenerate the bifunctional catalyst by the combustion of coke with air, at 300 °C (48 h). Under these conditions, the catalyst undergoes a slight Cu sintering in the first reaction-regeneration cycle but recovers completely the remaining activity in the successive cycles. [ABSTRACT FROM AUTHOR]

Carbon-based adsorbents were prepared through the physical activation of sewage sludge with CO2. The effect of the acid treatment was investigated, either before or after the physical activation. The post-washing increases the porosity due to the removal of the inorganic fraction and the improvement in the accessibility of the carbon fraction. The post-washing is essential for high activation temperatures since the high reactivity of CO2leads to a high pore blockage. In fact, the material activated at 900°C has a very low surface area (43 m2/g), while after washing it reaches 654 m2/g. The effect of the acid treatment prior to the physical activation depends on temperature: at 600°C, it results in a huge pore development (mainly macropores), while at 900°C, the microporosity increases. The adsorption capacity is not directly related to the BET surface area. For both adsorbates, the uptake ability depends on the textural properties (it is favoured by mesoporosity for methylene blue (MB) and microporosity for phenol) and surface chemistry (favourable effect of oxygen- and nitrogen-containing functional groups for MB and unfavourable effect for phenol). [ABSTRACT FROM AUTHOR]

This work is aimed at evaluating the performance of several catalysts in the partial hydrogenation of sunflower oil. The catalysts are composed of noble (Pd and Pt) and base metals (Ni, Co and Cu), supported on both silica and alumina. The following order can be proposed for the effect of the metal on the hydrogenation activity: Pd > Pt > Ni > Co > Cu. At a target iodine value of 70 (a typical value for oleomargarine), the production of trans isomers is minimum for supported nickel catalysts (25.7-32.4 %, depending on the operating conditions). Regarding the effect of the support, AlO allows for more active catalysts based on noble metals (Pd and Pt) and Co, the effect being much more pronounced for Pt. Binary mixtures of catalysts have been studied, in order to strike a balance between catalyst activity and product distribution. The results evidence that Pd/AlO-Co/SiO mixture has a good balance between activity and selectivity, and leads to a very low production of trans isomers (11.8 %) and a moderate amount of saturated stearic acid (13.5 %). Consequently, the utilization of cobalt-based catalysts (or the addition of cobalt to other metallic catalysts) could be considered a promising alternative for the hydrogenation of edible oil. [ABSTRACT FROM AUTHOR]

This work focuses on the influence of the support and the preparation method on the activity and selectivity of nickel catalysts in the hydrogenation of sunflower oil. Catalysts were prepared over silica and alumina supports following the incipient wetness impregnation and deposition-precipitation techniques. The activation process was followed by temperature-programmed reduction (TPR). Precipitation-deposition method allowed a stronger metal-support interaction than incipient wetness impregnation. A precipitation-deposition time of 14 h (which allowed a Ni loading of about 20wt%) was deemed as the most adequate from the standpoint of high specific surface area and strong Ni-support interaction. The selectivity to oleic acid was not affected by the preparation method, but it was significantly influenced by the type of support. In this regard, the catalysts prepared on silica are more active and produce less saturated fatty acids. [ABSTRACT FROM AUTHOR]

Microporous biochars, mainly composed by hydroxyapatite (HAp), were prepared from animal waste bones. In this study, a three-step procedure including pre-pyrolysis, chemical treatment with NaOH, KOH and KCO, and pyrolysis was investigated. The effects of the activation agent and its concentration were analysed by N adsorption-desorption, SEM, EDX, FTIR, and XRD techniques. The activation mechanism was investigated by TG-MS. FTIR and XRD data confirm that the obtained biochars were mainly composed of HAp. KCO was the most effective with porosity being increased by 30 % (up to 234 m/g) compared to non-alkali-treated sample. New pores were generated mainly in the microporous range. Analysis of the pyrolysis gases by MS revealed that the main effect of the alkali treatment is the incorporation of OH ions, which then react with bone matrix to generate porosity. Other gas-phase reactions, such as reverse WGS and methanation reactions, promoted by KCO, may be involved in the activation process. In contrast, KOH caused little modification of the HAp structure. Statistical analysis supported the relationship among the release of certain compounds during pyrolysis and the textural properties of the final material. [ABSTRACT FROM AUTHOR]

Bone is an inorganic template containing organic material inside which can be converted into hydroxyapatite-rich material by pyrolysis. Nowadays, there is a growing research interest in the use of hydroxyapatite, the chemical formula of which is Ca10( PO4)6( OH)2. In the present work, pork bone, an abundant biomass source and food waste, has been converted into structured porous hydroxyapatite by a three-step process including precharring under mild conditions, chemical activation, and thermal activation. The investigated activating agents were Na OH, KOH, K2 CO3, H2 SO4, and H3 PO4. A thorough investigation of the influence of different activating protocols on the chemical and textural properties of the produced material was carried out by nitrogen adsorption-desorption at 77 K, potentiometric titrations, Fourier transform infrared, and X-ray diffraction techniques. Chemical activation with Na OH, K2 CO3, and H2 SO4 increased the specific surface area up to 53%. H3 PO4 reduced both surface area and pore volume, and KOH showed little influence on the pore structure. The produced materials were evaluated by methylene blue adsorption tests and showed significant improvement as a result of chemical activation. As a main effect, acid treatment increased methylene blue adsorption kinetics, probably owing to an increase in micropororosity, whereas alkali activation enhanced the adsorption capacity of the resultant biochar. [ABSTRACT FROM AUTHOR]