Porous mullite honeycomb by hydrothermal treatment of fired kaolin bodies in NaOH

Hiroaki Katsuki, Sachiko Furuta, Atsunori Shiraishi, Sridhar Komarneni

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

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 5 N-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 5 N-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 2 N-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 5 N-NaOH solution at 190°C led to a decrease in specific surface area and therefore, these crystals should be avoided.

Original languageEnglish (US)
Pages (from-to)299-305
Number of pages7
JournalJournal of Porous Materials
Volume2
Issue number4
DOIs
StatePublished - Dec 1 1996

Fingerprint

Kaolin
Mullite
dissolving
Dissolution
Glass
glass
Crystals
crystals
Crystal whiskers
porosity
New Zealand
Crystal symmetry
silica glass
Fused silica
Specific surface area
Porosity
Crystallization
aluminosilicate
ceramics
Crystalline materials

All Science Journal Classification (ASJC) codes

  • Materials Science(all)
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Katsuki, Hiroaki ; Furuta, Sachiko ; Shiraishi, Atsunori ; Komarneni, Sridhar. / Porous mullite honeycomb by hydrothermal treatment of fired kaolin bodies in NaOH. In: Journal of Porous Materials. 1996 ; Vol. 2, No. 4. pp. 299-305.
@article{8639b3aa109f4230a1c560921731537f,
title = "Porous mullite honeycomb by hydrothermal treatment of fired kaolin bodies in NaOH",
abstract = "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 5 N-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 5 N-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 2 N-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 5 N-NaOH solution at 190°C led to a decrease in specific surface area and therefore, these crystals should be avoided.",
author = "Hiroaki Katsuki and Sachiko Furuta and Atsunori Shiraishi and Sridhar Komarneni",
year = "1996",
month = "12",
day = "1",
doi = "10.1007/BF00489811",
language = "English (US)",
volume = "2",
pages = "299--305",
journal = "Journal of Porous Materials",
issn = "1380-2224",
publisher = "Springer Netherlands",
number = "4",

}

Porous mullite honeycomb by hydrothermal treatment of fired kaolin bodies in NaOH. / Katsuki, Hiroaki; Furuta, Sachiko; Shiraishi, Atsunori; Komarneni, Sridhar.

In: Journal of Porous Materials, Vol. 2, No. 4, 01.12.1996, p. 299-305.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Porous mullite honeycomb by hydrothermal treatment of fired kaolin bodies in NaOH

AU - Katsuki, Hiroaki

AU - Furuta, Sachiko

AU - Shiraishi, Atsunori

AU - Komarneni, Sridhar

PY - 1996/12/1

Y1 - 1996/12/1

N2 - 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 5 N-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 5 N-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 2 N-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 5 N-NaOH solution at 190°C led to a decrease in specific surface area and therefore, these crystals should be avoided.

AB - 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 5 N-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 5 N-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 2 N-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 5 N-NaOH solution at 190°C led to a decrease in specific surface area and therefore, these crystals should be avoided.

UR - http://www.scopus.com/inward/record.url?scp=0029697738&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0029697738&partnerID=8YFLogxK

U2 - 10.1007/BF00489811

DO - 10.1007/BF00489811

M3 - Article

VL - 2

SP - 299

EP - 305

JO - Journal of Porous Materials

JF - Journal of Porous Materials

SN - 1380-2224

IS - 4

ER -