ÇEŞİTLİ AKTİVASYON YÖNTEMLERİNİN SEPİYOLİTİN YÜZEY ÖZELLİKLERİNE ETKİSİ

Abstract

In this study, it was aimed to improve the surface properties of β-sepiolite used as adsorbent material by grinding and chemical activation methods. In the first stageof the study, sepiolite samples were ground in dry, wet and cryogenic grinding media and different grinding times (1, 5, 10, 15 min). In the second stageof the study, chemical activation of β-sepiolite was carried out at two different acids (H3PO4(phosphoric acid) and HCl (hydrochloric acid) and three different acid concentrations (0.5M, 1M and 2M). In the thermal activation process, sepiolite samples were activated for 30 min at 100°C after impregnation with H3PO4(phosphoric acid) and HCl (hydrochloric acid) acid at three different acid concentrations. Surface area, micro and meso pore volumes and mean pore diameters of all obtained powders were determined by BET analysis and chemical content of sepiolite was examined by XRD analysis and Rietveld analysis. According to the comparisons, the highest surface area was obtained (268.20 m2/g) in dry grinding environment andthe highest surface area in chemical activation method was obtained (462.60 m2/g) in 1M H3PO4acid activation. In the thermal activation method the highest surface area (382.82 m2/g)was obtainedin 0.5M HCl pretreatedsample. Acid activation was found tobe more efficient in improving the surface properties of sepiolite.

Keywords

• sepiolite
• surface properties
• activation