Utilization of Extraction Procedures for Evaluating Environmental Risk from Waste Materials.

Several procedures for extracting content from different waste materials types were investigated, with the aim of evaluating their environmental impact. The waste materials consisted of wastes from bauxite ore processing by means of the Bayer process (red mud, Ajka, Hungary), bauxite ore using the sintering process followed by the Bayer process (brown-red mud, Žiar nad Hronom, Banská Bystrica region, Slovakia) and sulphide ores (metal-rich post-flotation tailing, Lintich, Slovakia). The extraction procedures were carried out with the aim of isolating "mobilizable" fractions using 0.

Removal of Impurities from EAFD Ammonium Carbonate Leachate and Upgrading the Purity of Prepared ZnO.

The paper describes cementation as a suitable method applied in the refining of EAFD leachates in order to obtain required purity of ZnO for specific industrial application. For study of cementation conditions, the leachate from alkaline leaching with (NH)CO was used. The leachates contained a high amount of zinc (8000-12,000 µg/mL) and a low content of impurities such as iron, lead, copper, chromium and manganese in the range of 1-21 µg/mL.

A Comprehensive View of the Optimization of Chromium (VI) Processing through the Application of Electrocoagulation Using a Pair of Steel Electrodes.

In the presented article, an electrocoagulation method using a steel cathode and a steel anode was used to obtain chromium from laboratory-prepared model solutions with known compositions. The study aimed to analyze the effect of solution conductivity, pH, and 100% efficiency of chromium removal from the solution, as well as the highest possible Cr/Fe ratio in the final solid product throughout the process of electrocoagulation. Different concentrations of chromium (VI) (100, 1000, and 2500 mg/L) and different pH values (4.

Optimization of simultaneous electrochemical determination of Cd(II), Pb(II), Cu(II) and Hg(II) at carbon nanotube-modified graphite electrodes.

The health of the environment is worsening every day. Monitoring of potentially toxic elements and remediation of environmental pollution are necessary. Therefore, the research and development of simple, inexpensive, portable and effective sensors is important.