Recovery of Gold and Other Precious Metals in Waste Ceramic CPUs and Phone Cards

Öz

Due to the increasing world population and the developing technological innovations, the rapidly increasing consumption of raw materials and as a result, the recycling of raw materials from waste products has gained importance. Especially in terms of precious metals, recovery is of great importance. In this study, it is aimed to recover precious metals from ceramic processors (CPU) in computers and mobile phone cards. This study, precious metals found in ceramic CPUs and telephone cards, which are electrical and electronic equipment (EEE) that have reached the end of their life, were obtained by using physical, hydrometallurgical and pyrometallurgical methods. The high value and limited reserves of minerals containing these precious metals make urban mining of precious metals very attractive. During the applied methods, precious metal amounts were measured with ICP-OES. In the study, besides other precious metals, the rate of gold (Au) in ceramic CPU was found to be approximately 1119 mg/kg. On the other hand, approximately 54.40 mg/kg of gold (Au) was detected in waste mobile phone cards.

Anahtar Kelimeler

• E-Waste
• Gold
• Hydrometallurgy
• Precious metal

Atık Seramik CPU ve Telefon Kartlarında Altın ve Diğer Değerli Metallerin Geri Kazanımı

Öz

Artan dünya nüfusu ile gelişen teknolojik yenilikler sonucunda hızla artan hammadde tüketimi ve bunun sonucunda oluşan atık ürünlerinden hammadde geri dönüşümü önem kazanmıştır. Özelliklede değerli metaller açısından geri kazanım çok büyük öneme sahiptir. Bu çalışmada, bilgisayarlarda bulunan seramik işlemci (CPU) ve cep telefonu kartlarından değerli metallerin geri kazanımı amaçlanmıştır. Çalışmada ömürlerinin sonuna gelmiş elektrikli ve elektronik ekipmanlarından (EEE) olan seramik CPU ve telefon kartlarında bulunan değerli metaller fiziksel, hidrometalurji ve pirometalurjik yöntemler kullanılarak elde edilmiştir. Bu değerli metalleri içeren minerallerin yüksek değeri ve sınırlı rezervleri, değerli metallerin kentsel madenciliğini çok çekici kılmaktadır. Uygulanan yöntemler sürecinde değerli metal miktarları ICP-OES ile ölçülmüştür. Çalışmada diğer değerli metallerin yanı sıra seramik CPU’da Altın(Au) oranı yaklaşık olarak 1119 mg/kg olarak bulunmuştur. Atık cep telefon kartlarında ise yaklaşık 54,40 mg/kg Altın(Au) tespit edilmiştir.

Anahtar Kelimeler

• Altın
• Değerli metal
• E-Atık
• Hidrometalürji

Kaynakça

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