caa a22 4500 47709175X CHVBK 20180405111517.0 cr unu---uuuuu 170330e19961201xx s 000 0 eng 10.1007/BF00489811 doi (NATIONALLICENCE)springer-10.1007/BF00489811 Porous mullite honeycomb by hydrothermal treatment of fired kaolin bodies in NaOH [Elektronische Daten] [Hiroaki Katsuki, Sachiko Furuta, Atsunori Shiraishi, Sridhar Komarneni] A conventional hydrothermal treatment with various concentrations of NaOH was used at 150° and 190°C to dissolve excess silica glass and thus make porous mullite ceramics from a fired New Zealand kaolin body. The effect of hydrothermal treatment time on the dissolution of the glass was examined. At 150°C, the dissolution of glass was almost complete after treatment for 8 hrs in 5N-NaOH solution and about 40-43 wt% of the glass was removed from the fired kaolin body leading to porous mullite. However, when the fired kaolin body was treated for more than 5 hrs in 5N-NaOH at 190°C, a composite of mullite and a nonporous crystalline phase of unknown symmetry resulted. These crystals formed from the dissolution and recrystallization of the glass. After the dissolution of glass in 2N-NaOH solution at 190°C for 5 hrs, a porous mullite body of 52.8% porosity with an average pore diameter of 0.57 μm could be obtained, and this was only composed of mullite whiskers. Growth of unidentified nonporous crystals in the body which was treated in 5N-NaOH solution at 190°C led to a decrease in specific surface area and therefore, these crystals should be avoided. Kluwer Academic Publishers, 1996 mullite honeycomb nationallicence hydrothermal treatment nationallicence fired kaolin body nationallicence porous mullite nationallicence Katsuki Hiroaki Saga Ceramics Research Laboratory, 3037-7, Arita-machi, 844, Saga, Japan aut Furuta Sachiko Saga Ceramics Research Laboratory, 3037-7, Arita-machi, 844, Saga, Japan aut Shiraishi Atsunori Saga Ceramics Research Laboratory, 3037-7, Arita-machi, 844, Saga, Japan aut Komarneni Sridhar Intercollege Materials Research Laboratory, and Department of Agronomy, The Pennsylvania State University, 16802-4801, University Park, PA, USA aut Journal of Porous Materials Springer Netherlands 2/4(1996-12-01), 299-305 1380-2224 2:4<299 1996 2 10934 https://doi.org/10.1007/BF00489811 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00489811 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Katsuki Hiroaki Saga Ceramics Research Laboratory, 3037-7, Arita-machi, 844, Saga, Japan aut NATIONALLICENCE 700 1- Furuta Sachiko Saga Ceramics Research Laboratory, 3037-7, Arita-machi, 844, Saga, Japan aut NATIONALLICENCE 700 1- Shiraishi Atsunori Saga Ceramics Research Laboratory, 3037-7, Arita-machi, 844, Saga, Japan aut NATIONALLICENCE 700 1- Komarneni Sridhar Intercollege Materials Research Laboratory, and Department of Agronomy, The Pennsylvania State University, 16802-4801, University Park, PA, USA aut NATIONALLICENCE 773 0- Journal of Porous Materials Springer Netherlands 2/4(1996-12-01), 299-305 1380-2224 2:4<299 1996 2 10934 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer