Piritin N2 Atmosferinde Isýl Bozunmasýna Su Buharýnýn Etkisi

Bu çalýþmada pirit mineralinin azot atmosferinde ýsýl bozunmasý üzerine su buharýnýn etkisi yatay bir boru fýrýn içinde incelendi. Deneysel parametreler olarak sýcaklýk, zaman ve su buharý konsantrasyonu kullanýldý. Azot/su buharý ortamýnda elde edilen verilere göre, piritin bozunmasý üzerine su buharýnýn bozunma hýzýný arttýrdýðý gözlemlendi. Bozunma reaksiyonunun, “büzülen çekirdek modeli” ile iyi uyum saðladýðý ve farklý hýz kontrol basamaklý iki bölgeye ayrýldýðý belirlendi. Hýz kontrol basamaklarý, düþük dönüþümlerde akýþkan filminden ýsý transfer kontrollü, yüksek dönüþümlerde ise kül filminden difüzyon kontrollü olduðu tespit edildi. Bu gaz ve kül filmi mekanizmalarýnýn aktivasyon enerjileri sýrasý ile 77 ve 81 kJ/mol-1 olarak bulundu.

The Effect of Water Vapor on the Thermal Decomposition of Pyrite in N2 Atmosphere

In this study, the effect of water vapor on the thermal decomposition of pyrite mineral in nitrogen atmosphere has been investigated in a horizontal tube furnace. Temperature, time and water vapor concentration were used as experimental parameters. According to the data obtained at nitrogen/ water vapor environment, it was observed that the water vapor on the decomposition of pyrite increased the decomposition rate. The decomposition reaction is well represented by the “shrinking core” model and can be divided into two regions with different rate controlling step. The rate controlling steps were determined from the heat transfer through the gas film for the low conversions, while it was determined from the mass transfer through product ash layer for the high conversions. The activation energies of this gas and ash film mechanisms were found to be 77 and 81 kJ/mol-1, respectively.