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Abstract In this research have been achieved the optimized experimental conditions to obtain the partial transesterification of sunflower oil with methanol, using CaO as an alkaline heterogeneous catalyst, to produce one mole of monoglicride (MG) and two moles of fatty acids methyl esters (FAME). This blend constitutes a new type of biofuel (Ecodiesel), applicable to diesel engines, which integrates the glycerine as monoglyceride (MG). Thus, similar results to those previously described by enzymatic partial alcoholysis of triglycerides are obtained through the kinetic control of the chemical reaction, so that the same type of biodiesel is obtained by using CaO, instead of the more expensive lipases. In order to obtain an improvement in conversion and kinematic viscosity, the influence on catalytic performance of several kinetic parameters was separately evaluated. It was obtained that a 6:1 molar ratio of methanol to oil, 7 wt% CaO catalyst, 65 °C reaction temperature, 60 min time reaction and 0.3% water content respect to oil, gave the best results. Besides, CaO catalyst maintained sustained activity after being repeatedly used for 20 cycles.

9 páginas, 6 tablas, 2 figuras. Effects of supplementing swine diets with phytase on manure composition and greenhouse gas (GHG) emissions from soil after manure application were investigated. The experiment was laid out in a completely randomised 3 × 2 × 2 factorial design, with three manure treatments (no manure, manure from unsupplemented diet and manure from phytase supplemented), two soils (Carman and Gunton sandy loam soils from Southern Manitoba, Canada) and two moisture levels (low and high moisture with 0.50 and 0.80 water-filled pore space, respectively). Gas emissions were greater (P < 0.05) from high than from low moisture soils. Manure addition increased CO and NO emissions. When applied to high moisture soils, CO emission was increased and that of NO decreased when phytase manure was applied compared with non-phytase manure. Methane emission was not affected by manure addition or by type of manure applied. Inorganic N remaining in soil at the end of the experiment was greater with phytase than with non-phytase manure application. Plant extractable P concentrations in soil were reduced with phytase manure, probably due to lower total P added with the manure. For a successful dietary strategy to reduce GHG from manure, a good understanding of the soil properties that influence emissions becomes necessary. Supplementation of swine diets with phytase contributes to reduce disposal of P and N in manure, but has a limited effect on GHG emissions from manure amended soils. Emission of NO may be reduced using manure from piglets fed phytase supplemented diets to fertilise high moisture soils. We are grateful to Trevor Fraser and Mervin Bilous for their help with laboratory work and we wish to thank Manitoba Pork Council and Manitoba Agriculture, Food and Rural Initiatives (MAFRI) for funding the study. The study was also, in part, supported by the Canada Research Chairs Program (grant 045867). Peer Reviewed

Abstract The process of spontaneous combustion of coal and coal waste gobs including emitted gases, condensation of inorganic and organic species in vents, and leachable potential are examined in this study which encompasses a literature review and new experimental data. Furthermore, the potential environmental benefits of cover soil reclamation for reduction of atmospheric and water leachable pollutant emissions are also considered. The Datong district (Shanxi province) is one of the most important coal production areas in China. The resulting large accumulations of mining waste are susceptible to spontaneous combustion. Three coal gangue dumps in the Datong region subjected to a range of reclamation conditions were investigated to assess the influence on coal fires. Coal, coal gangue, and condensates from gaseous emissions were characterized in terms of chemical composition, particle morphology, mineralogy, and leaching potential. The condensates include tar-like deposits, elemental sulfur, gypsum/anhydrite, ammonium and Hg salts, and a broad array of Al–K–Fe sulfates. The latter may give rise to strongly acidic leachates with high metal loads, which may pose a serious threat to the environment. These findings led to the development of a proposed condensation sequence model for coal gangue fires. The presence and distribution of organic compounds in the condensates deposited at vents were used as geothermometers in support of the proposed condensation model. Additionally, the present study has also explored some feasible remediation measures. It was found that covering these coal waste dumps with a layer of compacted soils appears to be an excellent cost-effective method to reduce spontaneous combustion, scavenge pollutants from gaseous emissions, and minimize risks associated with the leaching of readily soluble salts condensed on the surface.

The present paper evaluates the efficiency of sustainable activated carbons obtained from the valorization of lignocellulosic waste in removing siloxanes and volatile organic compounds for the purification of anaerobic digester biogas. Pyrolized and non-pyrolized lignocellulosic residues generated in food and wood industries were used as precursor materials to obtain experimental adsorbents by a chemical activation process using several activating agents. The highest porosity was obtained by non-pyrolized residue activated by K2CO3 at 900 °C. The performance of the experimental materials was compared with that of commercial activated carbons in gas adsorption tests of siloxanes (octamethylcyclotetrasiloxane and hexamethyldisiloxane) and volatile organic compounds (toluene and limonene). The waste-based activated carbons developed in this work proved to be more efficient for the removal of both siloxanes and VOCs than the commercial samples in most of the conditions tested. Adsorption capacities correlated with porosity, while the more relevant pore size depends on the adsorbate.

AbstractCorrosion is a crucial worldwide problem that strongly affects the oil and gas industry. Natural gas (NG) is a source of energy used in industrial, residential, commercial, and electric applications. The abundance of NG in many countries augurs a profitable situation for the vast energy industry. NG is considered friendlier to the environment and has lesser greenhouse gas emissions compared with other fossil fuels. In the last years, shale gas is increasingly exploited in the USA and in Europe, using a hydraulic fracturing (fracking) technique for releasing gas from the bedrock by injection of saline water, acidic chemicals, and sand to the wells. Various critical sectors of the NG industry infrastructure suffer from several types of corrosion: steel casings of production wells and their drilling equipment, gas-conveying pipelines including pumps and valves, plants for regasification of liquefied NG, and municipal networks of NG distribution to the consumers. Practical technologies that minimize or prevent corrosion include selection of corrosion-resistant engineering materials, cathodic protection, use of corrosion inhibitors, and application of external and internal paints, coatings, and linings. Typical cases of corrosion management in the NG industry are presented based on the authors’ experience and knowledge.

A relevant objective of the sulphuric acid (H2SO4) production industry today is to obtain sulphur dioxide (SO2) gas streams with the highest possible SO2 concentration after the elemental sulphur combustion stage in order to reduce both capital and operating costs. A new technology, Chemical Looping Combustion (CLC), is able to generate gaseous streams that are highly concentrated in combustion products by means of oxygen transfer from air to the fuel using a solid oxygen carrier. This work proposes a new process for H2SO4 production via CLC and using elemental sulphur as fuel. An oxygen carrier with high sulphur resistance should be used for this purpose. The analysis of this process has brought promising results, such as the easy integration of the CLC system into the entire H2SO4 production plant and the confirmation that this is a process in which the energy potential of sulphur is exploited to a very high degree. Furthermore, the proof of concept was carried out by burning elemental sulphur in a 500 Wth CLC unit with a high sulphur-resistant oxygen carrier based on iron oxide, Fe20γAl. This work presents the first ever results of elemental sulphur combustion by an oxygen carrier. Complete combustion of sulphur to SO2 was achieved, and no deactivation of the oxygen carrier was observed. Considering all the results obtained in this work, it can be concluded that the production of H2SO4 via CLC is a feasible technology which can provide a series of relevant techno-economic benefits in comparison with current industrial production process. This work has been financed by Shell Global Solutions International B.V. within the framework of the PT22648 agreement signed between Shell Global Solutions International B.V. and Instituto de Carboquímica – Consejo Superior de Investigaciones Científicas (ICB –CSIC). Peer reviewed

4 figures, 2 tables.-- Work presented at the GHGT-11,11th International Conference on Greenhouse Gas Control Technologies, 18-22 November 2012, Kyoto, Japan. Because of its low cost and environmental compatibility, Fe-based oxygen carriers are now being considered as an attractive option for chemical-looping combustion (CLC) applications. In this work, a synthetic Fe-based oxygen carrier made by impregnation using Al2O3 as support was evaluated with respect to gas combustion in a 500 Wth CLC continuous unit using CH4 as fuel during long-term operation. Furthermore, a study on the fate of sulfur during CH4 combustion was carried out with this oxygen carrier. During the experimental tests, it was observed that an increase in the oxygen carrier-to-fuel ratio (φ) produces an increase in the combustion efficiency, reaching full gas combustion at φ values 2 1.5. In addition, the presence of sulfur in the fuel gas did not affect to the combustion efficiency, independently of the amount of sulfur in the gas stream in the range of 700 to 2000 vppm H2S. However, the attrition of this oxygen carrier was higher than other materials used in CLC. Therefore, it can be concluded that the synthetic Fe-based oxygen carrier developed in this work was highly reactive and sulfur resistant and it can be considered as a suitable oxygen carrier for CLC with gaseous fuels that contain sulfur when the attrition behavior was improved. This paper is based on the work performed in the frame of the INNOCUOUS (Innovative Oxygen Carriers Uplifting Chemical Looping Combustion) Project, funded by the European Commission under the seventh Framework Programme (Contract No. 241401).