Mineralogy and thermal analysis of natural pozzolana opal shale with nano-pores

Abstract

Thermodynamic stability, microvoid distribution and phases transformation of natural pozzolana opal shale (POS) were studied systematically in this work. XRD analysis showed that opal-CT, including microcrystal cristobalite and tridymite, is a major component of POS. DTA and FT-IR indicated that there were many hydroxyl groups and acid sites on the surface of amorphous SiO₂ materials. FE-SEM analysis exhibited amorphous SiO₂ particles (opal-A) covering over stacking sequences microcrystal cristobalite and tridymite. Meanwhile, MIP analysis demonstrated that porosity and pore size distribution of POS remained uniform below 600 °C. Because stable porous microstructure is a key factor in improving photocatalyst activity, POS is suited to preparing highly active supported.

Keywords

pozzolana opal shale / cyclic utilization / thermal analysis / mineralogy analysis / nano-pore

References

[1] Sun ZM, Bai CH, Zheng SL, et al. A Comparative Study of Different Porous Amorphous Silica Minerals Supported TiO₂ Catalysts [J]. Applied Catalysis A, 2013, 458: 103-110.

[2] Zheng SL, Bai CH, Gao RQ. Preparation and Photocatalytic Property of TiO₂/Diatomite Based Porous Ceramics Composite Materials[J]. International Journal of Photoenergy, 2012, 10: 1-4.

[3] Sun ZM, Kong WA, Zheng SL, et al. Study on Preparation and Thermal Energy Storage Properties of Binary Paraffin Blends/Opal Shape-Stabilized Phase Change Materials[J]. Solar Energy Materials & Solar Cells, 2013, 117: 400-407.

[4] Li QS, Wang XW, Wu LN. Study on the Anion Additive Application in Rubber [J]. Journal of Functional Materials, 2004, 35: 2098-2105.

[5] Gu XH, Xi P, Li QS. Study of ABS/Nano-opal Composite[J]. China Plastics, 2006, 20: 27-30.

[6] Li QS, Chen J, Gao J. Nenjiang Opal Light Shale and Its Application in Polymer Materials[J]. China Non-metallic Minerals Industry, 2003, 36: 21-23.

[7] Wen M, Zheng SL, Liu Y. Study on Preparation and Application of Nano-TiO₂/Opal Composite Material[J]. Non-Metallic Mines, 2008, 31: 41-43.

[8] Liu C, Zheng SL, Song B. Preparation and Characterization of Nano-TiO₂/Opal Composite Materials[J]. Journal of Synthetic Crystals, 2013, 42: 695-700.

[9] Ren LF. The Discovery and Research of Light Shale Compose of Cristobalite and Tridymite[J]. Bulletin of the Chinese Ceramic Society, 1982, 2: 13-17.

[10] Bensted J, Barnes P. Structure and Performance of Cements, 2001 New York: Taylor & Francis.

[11] Wang BM, Zhang Y, Liu S. Influence of Carbon Nanofibers on the Mechanical Performance and Microstucture of Cement-based Materials [J]. Nanoscience and Nanotechnology, 2013, 5: 1112-1118.

[12] Brown LD, Ray AS, Thomas PS. 29Si and 27Al NMR Study of Amorphous and Paracrystalline Opals from Australia[J]. Journal of Non-Crystalline Solids, 2003, 332: 242-248.

[13] Jones JB, Segnit ER. The Nature of Opal I. Nomenclature and Constituent Chases[J]. Journal of the Geological Society Society of Australia, 1971, 18: 57-68.

[14] Graetsch H, Gies H Topalovi. NMR, XRD and IR Study on Microcrystalline Opals[J]. Phys. Chem. Minerals, 1994, 2: 166-175.

[15] Langer K, Flörke OW. Near Infrared Absorption Spectra (4000–9000 cm^-1) of Opals and the Role of “Water” in these SiO₂·nH₂O Mineral[J]. Fortschrift der Miner, 1974, 52: 17-51.

[16] Jessica ME, Stephen BR. TEM and X-ray Diffraction Evidence for Cristobalite and Tridymite Stacking Sequences in Opal[J]. Clays and Clay Minerals, 1996, 4: 492-500.

[17] Jones JB, Sanders JV, Segnit ER. Structure of Opal[J]. Nature, 1964, 4962: 990-991.

[18] Seriwat S, Frederick LS. Silica Phase-Transformations during Diagenesis within Petrified Woods Found in Fluvial Deposits from Thailand-Myanmar[J]. Sedimentary Geology, 2013, 290: 15-26.

[19] Ellis RL, Alvin VV, Charles EW, et al. Infrared Studies on Polymorphs of Silicon Dioxide and Germanium Dioxide[J]. Journal of Research of the National Bureau of Standards, 1958, 61: 61-70.

[20] Gates WP, Anderson JS, Raven MD, et al. Mineralogy of a Bentonite from Miles, Queenland, Australia and Characterization of Its Acid Activation Products[J]. Applied Clay Science, 2002, 20: 189-197.

[21] Hale B, Hamza Y, Yksel S. Thermal Analysis of a White Calcium Bentonite[J]. Therm Anal Calorim, 2010, 101: 873-879.

[22] George EC, Peter WS, Theodor M. Origin of the Bentonite Deposits of Eastern Milos, Aegean, Greece: Geological, Mineralogical and Geochemical Evidence[J]. Clays and Clay Minerals, 1995, 43: 63-77.