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The article focuses on the evaluation of PM2.5 and PM10, pollutants resulting from the metallurgical industry in Romania. The analysed period is 2008-2018 and the dataset was provided by the National Institute of Statistics. The purpose of this paper is to examine the impact of final energy consumption in the metallurgical industry on PM10 and PM2.5 emissions. We included in the study three fundamental factors: the final energy consumption in the metallurgical industry and the particulate matter (PM10 and PM2.5). The average of PM10 for reference period is 4026 Tone (Mg) while for the PM2.5 the average is 3645 Tone (Mg). The trend of final energy consumption in the metallurgical industry is identical to the trend of PM2.5 and PM10, which indicates that this factor has a major influence on the amount of PM2.5 and PM10 emissions. PM2.5 and PM10 emission factors represent primary emissions from the metallurgical industry activities and do not consider the formation of secondary aerosol from chemical reaction in the environment afterwards the discharge.

The raw materials of the metallurgical industry have an important chemical reactivity and when they come in contact with the environment, they can generate effects that in most cases are harmful. Chemical reactions from the solid / liquid interface showed a chemically active environment which caused the formation of reaction products with a certain degree of environmental damage.The paper aimed to address the interaction between some coarse (0.8 mm) and fine (0.04 mm) ferro-alloys (FeSi with 45% Si) with a physical simulation medium -distilled water for the possible determination of a change of pH. For this purpose, chemical composition determinations were made by the EDX method and the morphological characterization of the surfaces by the SEM electron scanning method. Also, pH measurements were made on different granulations and quantities of FeSi45.

Industrial wastewater can be properly treated using nanotechnologies and nanomaterials. This paper presents the synthesis and characterization of three series of magnetic nanoparticles (MNPs) and corresponding thin films, used for the degradation of organic compounds and removal of heavy metals from industrial wastewater. The samples were obtained by co-precipitation from a ferric (Fe3+) and ferrous (Fe2+) ions solution in a molar ratio of 2:1, at temperatures between 80-95 °C. The characterization of the samples was performed by scanning electron microscopy (SEM), and X-ray diffraction (XRD) methods. The magnetic nanoparticles were deposited on glass substrates by the centrifugal coating technique and the optical and magneto-optical activity was investigated by UV-Vis spectroscopy and magnetic circular dichroism technique (MCD). The effect of the investigated samples on the decomposition under UV irradiation of organic dyes was monitored by UV-Vis spectroscopy. Our preliminary results have shown that the magnetite and maghemite MNPs can be effective in UV degradation of methylene blue (MB) dye.

1050 Aluminum alloy samples polished electrochemically in solution of 15% Na2CO3 and 5% Na3PO4 were subjected to the anodic oxidation process in an acid electrolyte, of 1 M H2SO4 to which 1 g / L Al2(SO4)3 × 18 H2O was added for the formation on their active surfaces of aluminum oxide nanoporous layers by top-down nanotechnology method. The applied parameters during the anodic oxidation processes were varied in order to obtain the most uniform aluminum oxide nanoporous layers. Thus the potential was varied between 1 V and 25 V, the duration of the oxidation processes was between 10 minutes and 48 minutes and the stirring rate of the electrolyte was between 0 and 700 rotations per minute. The formation of nanoporous layers of aluminum oxide was observed when the applied potential was between 15 V and 21 V, the duration of the anodic oxidation process was varied between 25 and 45 minutes and the stirring rate of the electrolyte was between 0 and 500 rpm. Too low duration and / or too low potential caused an electrochemical polishing phenomenon to occur and the imposition of too high potential caused dissolution of the alloy substrate. Also, the use of a dynamic electrolyte regime produced a homogenization of the electrolyte temperature during the anodic oxidation processes and the growth of the aluminum oxide nanoporous film is slowed down. XRD diffractogram analysis reveals an enhancement in peak intensity correspondent to aluminum oxide concomitantly with a reduction in peak intensity of metallic aluminum for aluminum nanoporous oxide layers in comparison to the surface of polished Al1050 electrochemically.