Investigation of the Solubilities of Sulfated and Ground Phosphate Rock after Sulfation in H2SO4 Solution

Abstract

In this study, the effects of temperature and acid concentration on the dissolution of the sulfated and ground after sulfation phosphate samples in sulfuric acid solution obtained after flue gas desulfurization were investigated and the results were compared for both samples. It was observed that the dissolution rate increased as the temperature and acid concentration increased during the dissolution of sulfated and ground after sulfation phosphate samples. It was shown that the dissolution reaction can be divided into two regions, with different rate controlling steps for both samples. The controlling step was determined as pseudo-first order reaction at low conversions and diffusion through the product (ash) layer at high conversions.

Keywords

• Flue gas desulfurization, Sulfated phosphate rock, Dissolution kinetics

Sülfatlanan ve Sülfatlanma Sonrası Öğütülen Fosfat Kayasının H2SO4 Çözeltisinde Çözünürlüklerinin İncelenmesi

Öz

Bu çalışmada, baca gazı desülfürizasyonundan elde edilen sülfatlanmış ve sülfatlanma sonrası öğütülen fosfat örneklerinin H2SO4 çözeltisinde çözünürlükleri üzerine sıcaklık ve asit konsantrasyonunun etkileri incelendi ve her iki örnek için elde edilen sonuçlar karşılaştırıldı. Sülfatlanan ve sülfatlanma sonrası öğütülen fosfat örneklerinin çözünmesi esnasında sıcaklık ve asit konsantrasyonu arttıkça çözünme hızının arttığı gözlendi. Çözünme reaksiyonunun her iki örnek için farklı hız kontrol basamaklarına sahip iki bölgeye ayrılabileceği görüldü. Kontrol basamağının düşük dönüşümlerde yalancı birinci mertebe reaksiyon, yüksek dönüşümlerde ürün (kül) filminden difüzyon kontrollü olduğu belirlendi.

Anahtar Kelimeler

• Baca gazı desülfürizasyonu, Sülfatlanmış fosfat cevheri, Çözünme kinetiği

References

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