Oil Shale, 2007, Vol. 24, No. 3, pp. 476–482

 

DESULFURIZATION AND DEMINERALIZATION OF ASPHALTITE BY AQUEOUS CAUSTIC LEACHING

(full text in pdf format)

 

A. SAYDUT , M. Z. DUZ , C. HAMAMCI

 

The method of desulfurization and demineralization by aqueous caustic leaching (ACL) was used for treatment of asphaltite samples from Seguruk collieries of Sirnak asphaltite fields, situated in Southeast Anatolia region of Turkey. The effect of different parameters such as alkali concentration, time and temperature on leaching efficiency was studied, and the experimental results are presented here. The concentration of caustic was varied from 0.1 to 1.0 M, temperature from 100 to 180 °C, and leaching time from 4 to 16 h. Elevation of alkali concentration, leaching temperature and prolongation of time increase the removal of total sulfur and ash. As a result of ACL, ash content of asphaltite was reduced from 40.08 to 22.14%, and 75% of combustible was recovered. Total sulfur and volatile matter content was reduced from 6.74 to 2.49% and from 33.72 to 19.10%, respectively.

 

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