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Liver cirrhosis is a major cause of mortality worldwide. Adequate diagnosis and treatment of decompensating events requires of both medical skills and updated technical resources. The objectives of this study were to search the demographic profile of hospitalized cirrhotic patients in a group of Latin American hospitals and the availability of expertise/facilities for the diagnosis and therapy of decompensation episodes.

The potential of natural apatite derived from pork bones to be used as a support of Ni catalysts for the Water-Gas Shift (WGS) reaction was investigated. Samples of bone char were chemically treated with either K2CO3or H2SO4and subsequently heated in inert or oxidizing atmosphere at various temperatures. Catalysts were characterized by ICP-AES, N2physisorption, XRD, FTIR, TG-DTG, H2-TPR, XPS, H2chemisorption and NH3-TPD, and tested in the WGS reaction, using both ideal and realistic (mixture of H2O, CO2and H2) feed streams. Nickel was partly exchanged with Ca2+ions in the support. Regarding the effect of the atmosphere, an inert atmosphere had a negative effect due to the collapse of the porous structure. On the contrary, the combination of an oxidizing atmosphere and treatment with K2CO3allowed a superior WGS performance under real reformer conditions, with a substantial decrease in the methane formation (six-fold decrease, compared to the non-activated reference catalyst). The catalytic activity could be related to the apatitic phase growing geometry, which can be tailored by the activation method.

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 H2+ CO + CO2feeds. The runs have been conducted in a fixed bed reactor under the following conditions: 250–300 °C; 10–40 bar; 1.25–10.18 gcath molC−1; time on stream, 5–30 h; CO2/CO molar ratio, 0–1; feeding H2+ CO + CO2with a H2/COxmolar 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.

AbstractCarbon-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).

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).