6 research outputs found
Soil pollution in the Hungarian-Romanian border region (Valley of Körös-Cris rivers)
The investigation assessed and evaluated the soil polluting activities in 30 Romanian and Hungarian settlements in the region of the Double, Black and White Körös-Cris Rivers. Pb concentrations are mainly higher than the limit values with maximum values registered in the area of landfill and near the roads. The concentration of Cu and Zn in soils of the region is below the alarming values. In some places Cd levels in soils reached the alert threshold. Plant samples mostly do not contain higher than permitted levels of heavy metals. One of the main goals of the study is to contribute to the future sustainable use of the environment and conservation actions in the region in order to implement regional development policy. We must therefore address the social activities that involve a risk of soil pollution in the region, especially in the Körös-Cris Valley. Science-based assessment of the level of pollution can lead to the development of implementing procedures to reduce the impact of these activities. The most important result of the quality and quantity analysis of polluting activities in the region is territorial definition of soil heavy metal load
Oil wastewater coagulation with industrial waste iron coagulant
The study presents the results obtained during the coagulation of water with high content of oil compounds assessment as total petroleum hydrocarbon (TPH). Coagulation was carried out with a complex coagulation agent based on iron salts obtained from industrial waste. The control parameters of coagulation: turbidity, organic carbon (TOC), TPH, chemical oxygen demand (COD) in treated water samples with the optimal dose of coagulation agent based on iron salts obtained from industrial waste are similar to the residual values of the parameters determined in samples treated with the optimal dose of ferric chloride. The results obtained for the coagulation of oil wastewaters with optimal doses with different coagulation agents are supported also by the UV spectra. The advantage of the complex coagulation agent obtained from industrial waste was that it can be used for some wastewater in lower doses, by 25%, vs. ferric chloride
Fluoride removal from aqueous media by electrogenerated Al(OH)3
The removal of fluoride from aqueous media was carried out by electrocoagulation with aluminium sacrificial anode. The electrogenerated Al(OH)3 has high fluoride adsorption capacity. The applied current density was of 10, 30 and 50 A/m2 , respectively, the initial fluoride concentration was of 5 mg/L and 10 mg/L, respectively and pH of 7. The supporting electrolyte was 0.01 M Na Cl. Concentrations of fluoride in the electrolysed solutions of about 0.20 mg/L were obtained
Soil pollution in the Hungarian-Romanian border region (Valley of Körös-Cris rivers)
The investigation assessed and evaluated the soil polluting activities in 30 Romanian and Hungarian settlements in the region of the Double, Black and White Körös-Cris Rivers. Pb concentrations are mainly higher than the limit values with maximum values registered in the area of landfill and near the roads. The concentration of Cu and Zn in soils of the region is below the alarming values. In some places Cd levels in soils reached the alert threshold. Plant samples mostly do not contain higher than permitted levels of heavy metals. One of the main goals of the study is to contribute to the future sustainable use of the environment and conservation actions in the region in order to implement regional development policy. We must therefore address the social activities that involve a risk of soil pollution in the region, especially in the Körös-Cris Valley. Science-based assessment of the level of pollution can lead to the development of implementing procedures to reduce the impact of these activities. The most important result of the quality and quantity analysis of polluting activities in the region is territorial definition of soil heavy metal load
Copper recovery from spent catalyst used in COSORB processes
Environmentally responsible and sustainable waste management derived from technological processes represents an important priority marked by both national and EU legislation. Therefore, exploitation of chemical waste is considered as an obligation for each member state and, by default, for all the factors involved in the products life cycle and also an important economic opportunity. The main objective of our research project is to reduce the environment pollution with heavy metals and aromatic organic materials by recycling spent catalyst complexes resulted from industrial COSORB processes. In addition, it is economically desirable to recover the metals, which are usually copper and aluminum, from waste materials. Therefore, the present study aimed to develop a process for recovering copper from spent solutions of complexing agents containing cuprous aluminum tetrachloride. The liquid sorbent consisting of bimetallic CuAlCl4 in toluene and impurities has been subjected to several separation and analysis procedures for recovering and purification of metals and toluene. The process comprised of (i) treatment of spent solution with different solutions of sodium hydroxide, calcium hydroxide or water; (ii) separating the organic phase and the aqueous phase; (iii) contacting the aqueous phase containing the dissolved cuprous halide with iron, for precipitating copper metal and (iv) recovering the precipitated copper metal. The separation method employing water showed the best performances in terms of operational simplicity and cost-efficiency. The organic phase after separation contained 84.5 % toluene as major component, 10.0 % toluene oxidation products, 5.4 % xylene, and 0.1 % benzene traces. The inorganic phase contained about 98.5 g/L copper, 40.1 g/L aluminum, 20.0 mg/L zinc, 26.0 mg/L chromium and 18.0 mg/L iron. The yield of copper metal recovered from the spent solution was 91.9 % with 99.35 % purity
Influence of phosphorus and nitrates on the species development of Lemna minor L.
In this paper we wanted to determine the influence of phosphorus and nitrates in the development of Lemna minor L. To achieve this purpose, eight different growth variants were proposed, starting from the Hoagland culture medium, where the concentration of these two compounds varied. The growth rate in the eight experimental variants, ranges between 150% - 325%, with a minimum in the control sample and a maximum at the highest concentration of phosphorus in water