HİDROLİK ASİT ÇÖZELTİLERİ İLE UÇUCU KÜLDEN Ca, Mg VE Fe ÇÖZÜNÜRLÜĞÜ

Bu çalışma, Seyitömer (Kütahya) linyitik kömür yanma yan ürünü uçucu külden Ca, Mg ve Fe iyonlarının, konsantrasyonu 0,1–2N aralığında değişen HCI çözeltilerinde çözünebilirlik miktarının analizini içermektedir. XRD analizlerine göre uçucu kül, belirgin amorf ve kristalin kuvars fazlarının yanında, Fe, Al, Si, Ca, Mg metallerin bireysel ve kompleks oksit bileşiklerine ait fazlar içermektedir. Çözünürlük çalışmaları, uçucu külün ısıl işlenmemiş ve işlenmiş üç farklı örneğinde gerçekleştirilmiştir. Ca2+, Mg2+ ve Fe3+’in CaO, MgO ve Fe2O3 şeklindeki oksitleri cinsinden en yüksek çözünürlük değerleri 650oC’ta 2 saat ısıl işlenmiş kül örneğin 2N HCI çözeltisinde 6 saat liçi ile elde edilmiştir. En yüksek çözünürlük sonucuna göre, uçucu kül kompozisyonundan CaO, MgO ve Fe2O3 sırasıyla ve ağırlıkça yüzde olarak ~ %75, 93 ve 50 miktarında azalmıştır.

Anahtar Kelimeler:

Uçucu Kül, Çözünürlük

SOLUBILITY OF Ca, Mg AND Fe FROM FLY ASH IN HCI SOLUTIONS

A study on the solubility of Ca, Mg, and Fe from fly ash , a by-product of lignitic coal combustion in thermal power station from Seyitömer (Kutahya/Turkey), was performed using HCl acid with its several concentration varied in a range of 0.1 2 N. The X-ray diffraction analysis shows that the ash was found to be essentially amorphous phase and a significant amount of crystalline quartz, the individual and their complex oxides of Si, Al, Fe, Ca and Mg atom are also present low or uncertainity for detection by X-ray difraction. The Solubility studies were performed on three different forms of the ash that HK, KK1 and KK2 forms are as-received (untreated), heat treated at 650oC and 950oC for 2h, respectively. In the case of KK1, the maximum solubility levels were achieved with 2N HCl for 2h. The maximum solubilities in weight % were ~75, 93 and 50 for CaO, MgO and Fe2O3, respectively.

Keywords:

Fly Ash, Solubility,

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