Porous glass-ceramic bodies for catalyst supports

Claim 1

A GLASS-CERAMIC ARTICLES HAVING A USE TEMPERATURE OF AT LEAST 1,200*C., A COEFFICIENT OF THERMAL EXPANSION (25*-900*C.) LESS THAN 40 X 10**7/*C., AND AT LEAST A SURFACE PORTION OF RELATIVELY UNIFORM POROSITY WITH PORE DIAMETERS RANGING BETWEEN ABOUT 0.1-40 MICROMETERS TO PROVIDE A SURFACE AREA OF AOUT 1-100 METERS2/GRAM, SAID GLASS-CERAMIC BEING SELECTED FROM THE GROUP: A. CONSISTING ESSENTIALLY BY WEIGHT ON THE OXIDE BASIS, OF 2.5-5% LI2O, 2.5-8% BAO AND/OR MGO, 14-22% AI2O3, 60-75% SIO2, AND 3-8% RO2, WHEREIN RO2 CONSISTS OF 3-8% TIO2 AND O-3% ZRO2, AND WHEREIN THE PRINCIPAL CRYSTAL PHASE IS CELSIAN AND/OR CORDIERITE, B. CONSITING ESSENTIALLY, BE WEIGHT ON THE OXIDE BASIS, OF 2-15% LIO2, 12-13% AIO3, 55-75% SIO2, AND 3-7% TIO2 AND WHEREIN THE PRINCIPAL CRYSTAL PHASE IS BETASPODUMENE, C. CONSISTING ESSENTIALLY, BE WEIGHT ON THE OXIDE BASIS, OF 10-21% MGO.24-38% AI2O3, 48-60% SIO2, AND 8-12% TIO2, AND WHEREIN THE PRINCIPAL CRYSTAL PHASE IS CORDIERITE, AND D. CONSISTING ESSENTIALLY BY WEIGHT ON THE OXIDE BASIS, OF 35-70% AI2O3, 10-64% SIO2, AT LEAST ONE MODIFYING OXIDE IN THE INDICATED PROPORTION SELECTED FROM THE GROUP CONSISTING OF 1-20% P205, 1-5% LI2O, 4-10% NA2O, 4-10% SRO, 4-25% RB2O, 4-20% CS2O, 4-10% CAO, 4-10% SRO, 4-40% BAO, AND 4-20% LA2O3, THE TOTAL OOF SAID MODIFYING OXIDES NOT EXCEEDING 40% AND UP TO 40% TOTAL OF REFRACTORY OXIDES IN THE INDICATED PROPORTIONS SELECTED FROM THE GROUP CONSISTING OF 0-25% ZRO2, 0-30% THO2, 0-20% MGO, AND 0-10% BEO, AND WHEREIN THE PRINCIPAL CRYSTAL PHASE IS MULLITE.