Murat ERDEMOĞLU

Direct conversion of celestite ($SrSO_4$) to strontium carbonate by dry mechanochemical processing

Bu çalışmada, selestitin ($SrSO_4$) kuru mekanokimyasal süreçlerle doğrudan stronsiyum karbonata dönüşümü kinetik olarak incelenmiştir. Elde edilen dönüşüm-süre eğrileri katı haldeki ürün fazından difüzyon temeline dayalı farklı kinetik modeller kullanılarak değerlendirilmiştir. Kuru olarak selestitin tamamıyla stronsiyum karbonata dönüşümü 10 saatlik öğütmeyle bile sağlanamamıştır. %50 fazla sodyum karbonat kullanıldığı durumda görünür hız sabiti 0.00025 dak.-1'dır. Dönüşüm derecesi $Na_2CO_3/SrSO_4$ oranının 1,22. kuvvetiyle $([Na_2CO_3/SrSO_4]^122)$ orantılıdır.

Kuru mekanokimyasal olarak selestitin ($SrSO_4$) stronsiyum karbonata doğrudan dönüşümü

ABSTRACT: In this ,study, direct conversion of celestite ($SrSO_4$) to strontium carbonate by dry mechançchemical processing was kinetically studied. The resulting conversion-time curves were evaluated using different kinetic models based on the diffusion through the product phases in the solid-state. Complete conversion of celestite to strontium carbonate was never achieved by dry processing even in 10 h of milling. When 50% excess sodium carbonate was used, apparent rate constant is 0.00025 min~l. The order of conversion is proportional to 1.22 power of $Na_2CO_3/SrSO_4$ ratio $([Na_2CO_3/SrSO_4]^122)$.

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