• journal_title：Clay Minerals
• Contributor：Junping Zhang ; Qin Wang ; Hao Chen ; Aiqin Wang
• Publisher：Mineralogical Society of Great Britain and Ireland
• Date：2010-
• Format：text/html
• Language：en
• Identifier：10.1180/claymin.2010.045.2.145
• journal_abbrev：Clay Minerals
• issn：0009-8558
• volume：45
• issue：2
• firstpage：145
• section：Articles

The effects of acid activation on the chemical composition, surface area and pore structure of palygorskite from Xuyi (Jiangsu, P.R. China) were investigated systematically using X-ray fluorescence (XRF) and BET techniques. The palygorskite samples were activated with HCl, H₂SO₄ and H₃PO₄ of various concentrations at 80°C for 4 h. The influences of acid concentration and acid type on the chemical composition, adsorption-desorption isotherms at 77 K, pore-size distribution, surface area and pore volume were studied in detail. The contents of most components of palygorskite decrease with increasing acid concentration except for Si and Ti. HCl shows a greater activation activity and its effect on the dissolution of components of palygorskite is greater than that of H₂SO₄ and H₃PO₄. It was found that 3 mol l^–1 H₃PO₄ is a more efficient activator for increasing the number of micropores in palygorskite, whereas 12 mol l^–1 HCl is more suitable for use in enhancing the number of meso- and macropores. The acid concentration and acid type have a great influence on the surface area and pore volume. HCl is the most effective at enhancing the external surface area and mesopore volume of palygorskite, whereas, H₃PO₄ is more suitable for use in improving the micropore surface and volume.