Introduction: Antimony is one of the scarcest mineral resources among extractable global resources. According to Henckens et al. the extractable global resources of antimony will be used up before 2050 if the antimony extraction rate continues to increase with the current rate. This does not mean that antimony will have disappeared from the earth’s crust by that year, but the relatively easily extractable ores will. Antimony has consistently been ranked high in European and US Risk Lists concerning criticality of the element indicating the relative risk to the supply of chemical elements or element groups required to maintain the current economy and lifestyle. With most of the antimony imported into Europe and the US coming from China, Chinese production is critical to supply. As China is revising and increasing environmental control standards, antimony production is becoming increasingly restricted. Additionally, Chinese export quotas for antimony have been decreasing in the past years. These two factors increase supply risk for both Europe and US. Purpose: The aim of this study is to extract the antimony from its sulphide and oxide-containing ores of Kütahya-Gediz region by microwave leaching, meanwhile to eliminate the arsenic which is very hazardous for human health and environment, and finally to obtain metallic antimony and antimony oxide, which has potential to be used for further studies such as alloying metal or flame retardant agent. Scope: Using underground reserves of Turkey, extraction of antimony with hydrometallurgical processes, then refining of antimony ore in order to produce value added products of antimony were covered in this study. Limitations: In this research, main limitations are the obligation of hydrometallurgical process’ utilization instead of pyrometallurgical ones due to environmental concerns and also working with antimony ore in lieu of its concentrate. Method: Firstly, antimony was ground and dried, then homogenized for one week. Semi quantitative XRF analysis and XRD analysis were carried out. The antimony ore specimens were subsequently leached using hydrochloric acid in the presence of tartaric acid in a microwave oven. Afterwards, one part of the samples were precipitated as antimony trioxide at about pH 2 using caustic solution about 2 M. The other part of the samples was reduced to metallic antimony by NaBH4, subsequently washed with distilled water and dried with acetone. Following drying for 24 h at 105oC, the XRF, XRD analysis and SEM-EDS analysis were carried out on the pertinent samples. Results: The production of both antimony oxide and metallic antimony of more than 99 % of purity was achieved. The XRD results and EDS analyses proved the mono phase antimony trioxide and antimony peaks, respectively.
Conclusion: As a conclusion of this study, the production of both antimony trioxide and metallic antimony of more than 99 % of purity was achieved using Turkish antimony ore. Considering results of XRF, XRD and SEM + EDS analyses, it is found that the obtained products from Turkish ores can be directly used in various industrial processes.
Anahtar Kelimeler: Antimony, antimony trioxide, hydrometallurgy, flame retardants.
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