Multi-capillary monolith made from amorphous silica and/or activated alumina

Abstract

The invention relates to a monolithic porous material based on amorphous silica or activated alumina or on one of their mixtures, the material comprising substantially rectilinear capillary ducts that lie parallel to one another, and being intended to be used as packing in a chromatography column, characterised in that: the ducts have, relative to one another, a substantially uniform cross section; the cross-section of each duct is uniform over its entire length; the ducts pass right through the material; the volume of micropores smaller than 0.3 nm is smaller than 50% of the total porous volume of the material.

1 - 20 . (canceled) 
     
     
         21 . A packing for a chromatographic column, comprising a monolithic porous material based on a combination including amorphous silica and activated alumina and comprising substantially rectilinear capillary channels parallel to one another, wherein:
 said channels have a substantially uniform section relatively to each other, the average diameter of a channel not differing on average by more than 30% from the average diameters of the channels,   the section of each channel is regular over the whole of its length, the diameter of a channel not varying by more than a factor  2  between the most narrow areas and the widest areas,   said channels cross right through the material,   said channels have a diameter of less than 0.25 mm.   
     
     
         22 . The packing of  claim 21  wherein the total and cumulative length according to which the channels extend along a preferential direction of flow of a fluid is greater than or equal to 10 mm. 
     
     
         23 . The packing of  claim 21 , wherein the thickness of the wall between two adjacent channels in its thinnest portion, is less than half their diameter. 
     
     
         24 . The packing of  claim 21  wherein the monolithic porous material essentially consists of a clay. 
     
     
         25 . The packing of  claim 21 , wherein the capillary channels have a diameter of less than 0.1 mm. 
     
     
         26 . The packing of  claim 21 , wherein the monolithic porous material contains or supports a third party solid body. 
     
     
         27 . The packing of  claim 26 , wherein the third party solid body is a zeolite. 
     
     
         28 . The packing of  claim 21 , wherein the channels are totally or partly immersed in a porous mass and consist of stacked and juxtaposed segments. 
     
     
         29 . An axial or radial continuous annular chromatography apparatus comprising a packing, wherein the packing comprises a monolithic porous material based on a combination including amorphous silica and activated alumina and comprising substantially rectilinear capillary channels parallel to one another, wherein:
 said channels have a substantially uniform section relatively to each other, the average diameter of a channel not differing on average by more than 30% from the average diameters of the channels,   the section of each channel is regular over the whole of its length, the diameter of a channel not varying by more than a factor  2  between the most narrow areas and the widest areas,   said channels cross right through the material,   said channels have a diameter of less than 0.25 mm.   
     
     
         30 . A method for producing a packing comprising a monolithic porous material based on a combination including amorphous silica and activated alumina and comprising substantially rectilinear capillary channels parallel to one another, the method comprising the steps of:
 providing a bundle of so-called precursor fibres of the channels for which the diameter is equal to that of the capillary channels,   forming a porous matrix around fibres based on a combination including amorphous silica and activated alumina,   eliminating the fibres so as to form in said matrix, said capillary channels.   
     
     
         31 . The method of  claim 30  wherein the elimination of the fibres is achieved through lumens or interstices left free between the juxtaposed fibres of the bundle. 
     
     
         32 . The method of  claim 30  wherein the formation of a mineral solid porous matrix around the fibers is ensured by a sole gel method. 
     
     
         33 . The method of  claim 30  wherein the material is reinforced by depositing silica at the surface of the particles making it up before drying. 
     
     
         34 . A method for manufacturing a packing comprising a monolithic porous material based on a combination including amorphous silica and activated alumina and comprising substantially rectilinear capillary channels parallel to one another, the method comprising the steps of:
 forming a cross-linked silicone matrix comprising a load of a combination including amorphous silica and activated alumina around the fibres,   pyrolysis of the silicone so as to leave an amorphous silica residue binding the particles of the load.   
     
     
         35 . The packing of  claim 21  wherein the combination including amorphous silica and activated alumina is an aluminosilicate.