Research article
Vol 6 No 1 (2012): Volume 6, Number 1, 2012
Kinetika pelarutan silika amorf dari lumpur panas bumi Dieng
Jurusan Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika 2 Yogyakarta
Jurusan Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika 2 Yogyakarta
Jurusan Teknik Kimia, Fakultas Teknik, Universitas Gadjah Mada Jl. Grafika 2 Yogyakarta
Abstract
Dieng’s geothermal power plant generates not only energy but also wastes as sludge that contains around 50% silica in an amorphous state. The waste has a great potential to be used as a source of micro-amorphous silica synthesis to fulfill industrial needs. This research aimed to study the dissolution kinetics of amorphous silica. In the present work, the alkali – solubilization process by means of the dissolution of amorphous silica in an agitated flask was studied by varying process temperatures (50 – 90 °C), stirring speed (150 – 450 rpm), Na/Si molar ratio (2 – 3), and silica particle size (0,0069 – 0,01975 cm). Experimental results showed that the rate of geothermal silica dissolution increased with temperature and stirring speed. Meanwhile, Na/Si molar ratios and silica particle sizes showed no significant influence on the dissolution process. Calculation results indicated that the dissolution process involved a solid – liquid reaction that occured at the solid surface.
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