MEHMET KAYRA TANAYDIN, NİZAMETTİN DEMİRKIRAN

Malahit Cevherinin Perklorik Asit Çözeltilerindeki Çözünürlüğünün İncelenmesi

Hidrometalurji sulu çözeltilerde kimyasal reaksiyonlar vasıtasıyla metal, metal tuzları ve bileşiklerinin üretimini kapsar. Oksitli bakır cevherlerindeki bakır, hidrometalurjik yöntemler yardımıyla kazanılabilir. Sözü edilen metodun ilk aşaması katı-sıvı kütle transferini içeren liç prosesidir. Bu proseste katı cevher uygun bir çözücü ile çözündürülür ve metal değerler çözelti ortamına transfer edilir. Mevcut çalışmada, oksitli bir bakır cevheri olan malahitin sulu perklorik asit çözeltilerindeki çözünürlüğü incelenmiştir. Malahit cevherindeki bakır, çinko ve demirin çözünme davranışı belirlenmiştir. Cevherdeki bakırın çözünürlüğü üzerine asit derişimi, reaksiyon sıcaklığı, ortalama katı tanecik boyutu, katı/sıvı oranı ve karıştırma hızının etkileri araştırılmıştır. Bütün deneysel parametrelerin bakırın çözünmesi üzerinde önemli bir etkiye sahip oldukları gözlenmiştir. Asit derişimi, reaksiyon sıcaklığı ve karıştırma hızının artmasıyla, katı/sıvı oranı ve katı tanecik boyutunun ise azalmasıyla cevherdeki bakır liçinin arttığı tespit edilmiştir. Cevherdeki demirin çözünürlüğünün asit derişiminden oldukça etkilendiği gözlenmiştir. Reaksiyon koşullarının kontrol edilmesiyle çözelti ortamına geçen bakır miktarının yüksek, demir miktarının ise düşük seviyelerde tutulabileceği belirlenmiştir. Liç prosesi ile ilgili kinetik analiz yapılmış ve reaksiyon hızının karışık kinetik kontrollü modele uyduğu belirlenmiştir. Liç prosesinin aktivasyon enerjisi 30,94 kJ/mol olarak hesaplanmıştır

Investigation of Dissolution of Malachite Ore in Perchloric Acid Solutions

Hydrometallurgy contains the production of metal, metal salts, and their compounds by means of chemical reactions in aqueous solutions. Copper in the oxidized copper ores can be recovered by hydrometallurgical methods. First step of the mentioned method is the leaching process involving a solid to liquid mass transfer. In this process, solid ore is dissolved by an appropriate solvent, and metal values are transferred into solution medium. In the present study, it was examined dissolution of malachite, which is an oxidized copper ore, in aqueous perchloric acid solutions. The dissolution behavior of copper, zinc, and iron in the malachite ore was determined. The effects of acid concentration, reaction temperature, average particle size of solid, solid-to-liquid ratio, and stirring speed on dissolution of copper in the ore were investigated. It was observed that all experimental parameters have a significant effect on the leaching of copper. It was determined that the leaching of copper in the ore increased with an increase in acid concentration, reaction temperature and stirring speed, and with a decrease solid-toliquid ratio and in solid particle size. It was observed that the dissolution of iron in the ore was substantially affected from acid concentration. By controlling of the reaction conditions, it was found that the amount of copper passing to the solution medium can be high and the amount of iron can be kept at low levels. The kinetic analysis relating to the leaching process was made, and it was determined that the reaction rate followed the mixed kinetic controlled model. The activation energy of the leaching process was estimated to be 30.94 kJ/mol

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