Investigation of Fractal Dimension Change in Synthesized CaSO4 Using PSSS

Year 2018, Volume: 1 Issue: 1, 72 - 79, 06.08.2018

Mücahit Uğur

Abstract

Generally, commercial product of
calcium sulfate anhydrous (CaSO₄) is synthesized burning gypsum in
kiln, in the process that the water is removed from gypsum crystallized by
mixing CaCl₂ and Na₂SO₄ in aqueous medium. It
is possible to change gypsum properties by changing the parameters during
crystallization. Also, the differentiation in the structures of the synthesized
product can be possible with using additives during the crystallization. The
changes in properties of these synthetically produced materials may be
investigated instrumentally.

This study examines change of
surface fractal dimensions (D_f) of synthesized CaSO₄ anhydrate
instrumentally. CaSO₄.2H₂O was synthesized by chemical
precipitation method in the presence Poly(Sodium 4-Styrene Sulphonate) and
measured N₂-physisorption measurements after burning. Fractal
dimensions were determined using single N₂-adsorption/desorption
isotherms method. For Fractal dimension calculations, the Frenkel–Halsey–Hill
(FHH) and the Neimark–Kiselev (NK) methods were used. Taguchi method has been
used in evaluation of experimental design for optimization of D_f
values.

Keywords

Crystallization, Df value

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