The Geological Occurrence, Mineralogy, and Processing by Flotation of Platinum Group Minerals (PGMs) in South Africa and Russia

Russia and South Africa are the world’s leading producers of platinum group elements (PGEs). This places them in a unique position regarding the supply of these two key industrial commodities. The purpose of this paper is to provide a comparative high-level overview of aspects of the geological occurrence, mineralogy, and processing by flotation of the platinum group minerals (PGMs) found in each country. A summary of some of the major challenges faced in each country in terms of the concentration of the ores by flotation is presented alongside the opportunities that exist to increase the production of the respective metals. These include the more efficient recovery of minerals such as arsenides and tellurides, the management of siliceous gangue and chromite in the processing of these ores, and, especially in Russia, the development of novel processing routes to recover PGEs from relatively low grade ores occurring in dunites, black shale ores and in vanadium-iron-titanium-sulphide oxide formations.

Curcumin - Properties, Applications and Modification of Structure

In recent years, the interest in biologically active compounds of natural origin has increased significantly. Researchers' research focuses on increasing the activity of curcumin by forming complexes with metals such as vanadium, iron, copper or gallium. Introduction of metal compounds to curcumin increases the scope of application in pharmacology. The main direction of research development is the treatment of tumors, among others stomach cancer or leukemia. Curcuminoids are the main components of turmeric (Curcuma longa L.), a plant from India and South-East Asia. Due to its intense yellow-orange color and pleasant aroma, the powdered rootstalk is widely used in the food industry, as natural dye and spice. The chemical compound responsible for the characteristic color of rhizomes of curcuma is 1,6-heptadien-3,5-dione-1,7-bis(4-hydroxy-3-methoxyphenyl) - (1E, 6E) called curcumin. This work aims to characterize curcumin in terms of its structure, therapeutic properties and also as a substrate for the synthesis of valuable derivatives like tetrahydrocurcumin. Knowledge about this relationship based on literature analysis will enable a better understanding of the factors responsible for its biological activity.

PENGGUNAAN ANALISIS DISKRIMINAN UNTUK KLASIFIKASI SUBPOPULASI BATU PASIR BERDASARKAN KANDUNGAN MINYAK MENTAH

The application of discriminant analysis of crude oil content in two populations of sand stone is todetermine the independent variables that could significantly differiantiate between a rock that contains fivevariables, namely crude oil Vanadium, Iron, Beryllium, Hydrocarbon, and Aromatic Hydrocarbon Saturade. Theanalys of data from five independent variables, the variables that can distuingish between the two populations isvariable Saturade sand stone Hydrocarbon, Iron, and Vanadium. Therefore, these three variables used informingthe discriminant function and classification process. The classification result using the SPSS program showed thatthe discriminant function is significant and validation of the discriminant function obtained test classificationaccuracy of 93,9 %.

Recycling of Oil Fly Ash in the Adsorption of Dyes From Industrial Wastewater

The use of oil fly ash after the recovery of heavy valuable metals was investigated. More specifically, its use, as an adsorbent of dyes from industrial wastewater, was evaluated. Methylene blue was used as a model compound to study the adsorption capacity of the proposed carbonaceous residue from metal recovery treatments. The effects of contact time, initial dye concentration, and absorbent dose were investigated. The maximum amount of dye was adsorbed after one hour. Moreover, 1-3 g of residues were necessary for the removal of 200-1000 mg dm–3 from 0.050 dm3 of contacted solution. The Langmuir isotherm model was in good agreement with the adsorption equilibrium data, indicating a maximum monolayer saturation capacity of approximately 40 mg/g at 25 °C. High abatement efficiencies (up to 99 %) were obtained, and the adsorbed dye was released almost immediately by re-contacting with water. The adsorption capacity was at least four times lower than that of commercially available active carbon. The double treatment of oil fly ash with deionised water and hydrochloric acid allows for the extraction of over 85 % of the vanadium, iron, and nickel content in the ash. However, the negligible or zero cost of solid residues, otherwise disposed in landfills, indicates their potential as a valid alternative. The use of oil fly ash for both recovery of heavy valuable metals and the subsequent removal of dyes from wastewater suggest a zero-waste process.