powder productıon and nano materıals - 6th International Powder ...

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6. ULUSLARARASI TOZ METALURJİSİ KONFERANSI ve SERGİSİ
th INTERNATIONAL POWDER METALLURGY CONFERENCE & EXHIBITION
Figure 2. XRD pattern of leached clinoptilolite powder.
table 1. Chemical composition of the as-received and leached clinoptilolite (wt.%).
Oxides SiO 2 Al 2 O 3 K 2 O Fe 2 O 3 CaO Na 2 O MgO TiO 2 MnO P 2 O 5 SO 3
As-received 83.88 8.27 3.67 1.77 1.81 0.26 0.64 0.10 0.04 0.02 0.02
Leached 97.50 1.00 1.10 0.48 0.084 0.02 0.31 0.07 0.01 0.02 0,02
3.4. ınfluence of leaching times on particle size and distribution
The size distributions of the untreated and leached clinoptilolite powders were investigated by zeta sizer (Malvern-
Nano S). Fig. 3 presents the plot of cumulative mass percent finer versus particle size. After leaching the particle
size of the sample became finer due to fracture of the large particles and the sample acquired a monomial and
narrow size distribution.
Figure 3. Size distributions of raw and leached clinoptilolite powders.
3.5. ınfluence of leaching on the specific surface area
The BET surface area values of the raw and leached powders are given in Table 2. As evident from the table, the
surface area of clinoptilolite greatly increased after the leaching. The reason for the increase in the specific surface
area could mainly be due to the breakdown and/or very intensive erosion of the larger particles through the longterm
processing.
table 2. Specific surface area of the clinoptilolite with and without leaching.
Samples Specific surface area, m 2 /g
Raw clinoptilolite 47.87
Leached clinoptilolite 154.30
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