Cl2 gazı ile doyurulmuş HCI çözeltilerinde altın hurdalarından altının liçing kinetiği

Öz

Altın içeren hurdalardan altının liçingi üzerine kinetiği ortaya koyan modeli açıklamak için, reaksiyon sıcaklığı, asit konsantrasyonu, katı-sıvı oranı, karıştırma hızı ve partikül boyutunun etkileri araştırılmıştır. Cl2 ile doyurulmuş HCI çözeltilerindeki altın liç kinetiğinin incelenmesinde, ortamda meydana gelen Cl atomları, altın hurdaları ile Cl2 moleküllerine göre daha hızlı reaksiyon vermektedir. Bu reaksiyon, çözünme reaksiyonu ile eşzamanlı olarak gerçekleşir ve yerinde oluşturulan klor olarak isim alır. Yöntemin, üretilen klorun depolanması gibi bazı dezavantajları da yoktur. Liçing hızının, artan reaksiyon sıcaklığı, karıştırma hızı ve asit konsantrasyonunu ile artarken; katı-sıvı oranı ve partikül boyutunun artmasıyla azaldığı belirlenmiştir. Katı-sıvı sistemleri için büzülen nüve modellerini kullanan deneysel veriler analiz edilerek, altın içeren hurdalardaki altının liçinginin kimyasal kontrollü olduğu gözlenmiştir. Keza; çözünmenin kimyasal reaksiyon ile kontrol edilen liçing hızı, hız sabiti ve partikül boyutu arasındaki ilişki ile de desteklenmiştir. Liçing prosesinin aktivasyon enerjisi Statistica Paket Programı kullanılarak 34.40 kJ/mol olarak tespit edilmiştir.

Anahtar Kelimeler

• Altın içeren hurdalar,Klor gazı,Liçing kinetiği

The leaching kinetics of gold from gold scraps in Cl2-saturated HCl solutions

Abstract

In order to explain the model of kinetics control on the leaching of gold in gold-bearing scraps, the effects of the reaction temperature, solid/ liquid ratio, particle size and stirring speed and acid concentration are investigated. In the examination of the leaching kinetics of gold in Cl2-saturated HCI solutions, Cl atoms occurring in the medium react more rapidly than Cl2 molecules with gold scraps. This reaction takes place simultaneously with the reaction of dissolution and in situ-generated chlorine is called. Also, the method doesn’t have some disadvantages such as the storage of generated chlorine. It is determined that the leaching rate decreases with increasing particle size and solid to liquid ratio while it increases with increasing reaction temperature, acid concentration and stirring speed. For fluid/solid systems, shrinking core models are analysed by using of experimental results. It is observed that the leaching of gold from gold-bearing scraps is chemically controlled. Also, the leaching rate controlled by the chemical reaction is supported by the relationship between the particle diameter and rate constant. The activation energy of leaching process by using Statistica Package Program is determined as 34.40 kJ/mol.

Keywords

• Gold-bearing scraps,Chlorine,Leaching kinetics

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