Back to results
US 2002/0165081 A1Published application
Halogen-resistant media
AssigneeSaint-Gobain Norpro Corporation
InventorsJohn S. Reid, Thomas Szymanski, Karen C. Beal
Life of this patent
Estimating the term…
Abstract
Ceramic mass transfer media suitable for use in thermal regenerative oxidizers made using a mixture of a clay, talc and optionally a dolomitic limestone have enhanced resistance to environments containing halogens and hydrogen halides.
Claims19
Ceramic media comprising less than 0.25% by weight of alkali metal, measured as the oxide, formed from a fired mixture comprising 10 to 98%, by weight a clay having an alumina content of at least 36% by weight;
- from 2 to 90% by weight of a talc containing at least 95% by weight of magnesium silicate as determined by X-ray diffraction analysis;
- and from 0 to 10% by weight of a dolomitic limestone containing 60 to 90% by weight of calcium carbonate and 10% to 40% by weight of magnesium carbonate and less than 10% of non-carbonate impurities.
A process for the production of ceramic media which comprises:
- a) forming a mixture comprising 10 to 98%, by weight a clay having an alumina content of at least 36% by weight;
- from 2 to 90% by weight of a talc containing at least 95% by weight of magnesium silicate as determined by X-ray diffraction analysis;
- and from 0 to 10% by weight of a dolomitic limestone containing 60 to 90% by weight of calcium carbonate and 10% to 40% by weight of magnesium carbonate and less than 10% of non-carbonate impurities, the mixture containing less than 0.25% by weight of alkali metals, measured as the corresponding alkali metal oxides in the product remaining after firing;
- b) adding water in an amount sufficient to make a shapeable product;
- c) shaping the product to a desired shape;
- and
- d) calcining the shaped product at a temperature of from 1100° C. to 1400° C.
4 more elements
Dependencies are inferred from the claim text.