University of Huelva posted this:New procedure for the purification of water contaminated by metals and the respective systemsThe invention solves the problems of inefficiency which usually shows the conventional passive treatment systems. The reactive fills developed for the removal of inorganic contaminants historically have focused on removing low concentrations of these (typical features of coal mining), however when these fillers are faced to high concentrations of metals (sulfur mining, uranium, industrial water waste…) quickly clogging and loss of reactivity occurs. The present invention allows the removal of metals without clogging and/or loss of reactivity. This is achieved by the use of a coarse inert material with high surface mixed with a fine-grained reactive material, so that the surface of the inert material is breaded with reactive material. Coarse fragments of inert material act as a frame, providing large pores that reduces clogging by precipitates. The small particle size of the reactive material provides a large surface area that increases its reactivity.
uacoopera posted this:Tungsten carbide based composite material, the appropriate method of production and applicationThe preferential production method of the composite material involves the sputtering for the modification of the particle surface by coating them with a nanocrystalline layer of iron-rich metallic binder with variable thickness. The rest of the processing follows the traditional powder metallurgy routes with pressing and sintering in a vacuum furnace. After processing, the composite contains tungsten carbide phase, eta-phase and iron rich binder.
Centre Technology Transfer CITTRU posted this:Catalysts for low-temperature combustion of methane from low-caloric sources and methods for their preparationDue to the rising emission of methane and its extensive contribution to the greenhouse effect, the reduction of CH4 emissions from low-caloric anthropogenic sources is currently a vital importance. The main sources of the methane emission are: exploitation of oil pools, coal mining, pas power stations, landfills, agriculture and biomass. The most popular method of the reduction of methane is its catalytic combustion. Unfortunately, this method has few limitations associated mainly with hard activation of the C-H bond in CH4 and low concentrations of methane in the emitted gases. The catalytic oxidation of methane is limited also by the very large airflows (of order 105 m3/min), passing through the catalyst bed during the process. There is still a lack on the market of a technological solution based on total catalytic combustion of CH4 in the economically reasonable low-temperature window, i.e. below 400 °C. The most popular method among the methods limiting the emission of methane to the atmosphere is the one based on its catalytic combustion. However, this procedure has disadvantages, mainly due to the high activation energy of methane molecules and also because of the low concentration of methane emitted from anthropogenic sources. There is no technology allowing effectively combusting of methane with the concentration of 1-2 % and in the economically justified temperatures, i.e. lower than 400 °C. The fundamental advantages of offered solutions are: - method for preparing catalysts that ensures the repeatability of the parameters and high efficiency in the reactions of methane combustion, - increased both the activity and the thermal stability of the catalysts in comparison with other systems described in the literature, - possibility of using the catalysts in the total oxidation of methane emitted from the low-caloric sources at temperatures below 400 °C.