Title:
【発明の名称】リン酸亜鉛分子ふるい並びにその吸着および触媒反応における利用
Document Type and Number:
Japanese Patent JPH0818821
Kind Code:
B2
Abstract:
Substantially crack-free ceramic articles having less than 5% porosity are prepared in a two-step process starting with a potassium- or cesium- or rubidium-exchanged zeolite or mixtures thereof, the zeolite being characterized in that it has an SiO2/Al2O3 ratio of 3.5:1 to 7.5:1, and calcining it in a first step at a temperature of 900 DEG to 1100 DEG C for a time sufficient to collapse the zeolite framework and provide an amorphous powder. Next, the amorphous powder is formed into a shaped article and the article is sintered in a second step at a temperature of 1150 DEG to 1400 DEG C for a time of 0.5 to 12 hours to give a ceramic article. The principal crystalline phase of the ceramic article is tetragonal leucite when potassium-exchanged zeolite is used. When the zeolite is exchanged with cesium a ceramic article whose principal crystalline phase is pollucite is obtained. When a rubidium-exchanged zeolite is used a ceramic article whose principal crystalline phase is rubidium leucite is obtained. When a potassium/cesium-exchanged zeolite is used a ceramic article having as its principal crystalline phase a leucite/pollucite solid solution is obtained. The addition of pollucite to the leucite article provides a ceramic article whose thermal expansion coefficient can be varied from 2 x 10<-><6> to 27 x 10<-><6> DEG C<-><1> as measured over the range 50 DEG to 700 DEG C.
Inventors:
Robert El. Vaderd
Application Number:
JP19476792A
Publication Date:
February 28, 1996
Filing Date:
June 29, 1992
Export Citation:
Assignee:
UOP
International Classes:
B01J20/02; B01J29/04; C01B25/45; C01B37/00; C01B39/06; C01B39/46; C01B39/52; C01B39/54; C04B35/19; C07B61/00; C10G45/12; C10G47/16; C10G47/20; C10G49/08; (IPC1-7): C01B39/54; B01J20/02; B01J29/04; C01B25/45; C10G45/12; C10G47/20; C10G49/08
Attorney, Agent or Firm:
Morio Sada
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