Crush-resistant/adsorptive agglomerates of activated alumina
AssigneeRhone-Poulenc Chimie
InventorsThierry Chopin, Patrick Fourre, Philippe Jaeger, Bernard Taxil
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Abstract
Activated alumina agglomerates having a crush resistance of at least 12 daN, measured on that fraction thereof having a mean diameter ranging from 3 to 4 mm, and an adsorptive capacity greater than 18% by weight, well adopted as adsorbents in a wide variety of purification processes, are prepared by agglomerating activated alumina particulates, maturing the resulting agglomerates in the presence of a complexing agent for the cation Al.sup.3+, and then thermally treating the matured agglomerates at a temperature ranging from about 100.degree. to 500.degree. C.
Claims12
A process for the preparation of activated alumina agglomerates having a crush resistance of at least 12 daN, measured on that fraction thereof having a mean diameter ranging from 3 to 4 mm, and an adsorptive capacity greater than 18% by weight, comprising agglomerating activated alumina particulates, maturing the resulting agglomerates in the presence of a complexing agent for the cation Al.sup.3+, and then thermally treating the matured agglomerates at a temperature ranging from about 100.degree. to 500.degree. C., said complexing agent comprising a phosphorus acid having one of the following formulae (I) to (III):
- ##STR3## in which formulae (I) to (III), n and m are integers ranging from 1 to 6;
- p is an integer ranging from 0 to 5;
- and R.sub.1, R.sub.2 and R.sub.3, which may be identical or different, each represents a hydrogen atom or an alkyl, aryl, aralkyl, hydroxy or amino radical.
A process for the preparation of activated alumina agglomerates having a crush resistance of at least 12 daN, measured on that fraction thereof having a mean diameter ranging from 3 to 4 mm, and an adsorptive capacity greater than 18% by weight comprising agglomerating activated alumina particulates, maturing the resulting agglomerates in the presence of a complexing agent for the cation Al.sup.3+, and then thermally treating the matured agglomerates at a temperature ranging from about 100.degree. to 500.degree. C., said complexing agent comprising methylene aminotriphosphonate, methylene ethylenediaminotetraphosphonate, methyl triethylenetetraaminohexaphosphonate, methylene tetra-ethylenepentaaminoheptaphosphonate, methylene pentaethylenehexaaminooctaphosphonate;
- a diphosphonate of methylene, 1,1'-ethylene, 1,2-ethylene, 1,1'-propylene, 1,3-propylene, and 1,6-hexamethylene;
- 2,4-dihydroxypentamethylene-2,4-diphosphonate;
- 2,5-dihydroxyhexa-methylene-2,5-diphosphonate;
- 2,3-dihydroxybutylene-2,3-di-phosphonate;
- 1-hydroxybenzyl-1,1'-diphosphonate;
- 1-amino-ethylene-1,1'-diphosphonate;
- hydroxymethylene diphosphonate;
- hydroxyethylene-1,1'-diphosphonate;
- 1-hydroxypropylene-1,1'-diphosphonate;
- 1-hydroxybutylene-1,1'-diphosphonate;
- or 1-hydroxyhexamethylene-1,1'-diphosphonate.
Dependencies are inferred from the claim text.