Carbon-clad zirconium oxide particles

Abstract

Carbon-clad zirconium oxide particles are disclosed which are useful in sorbent applications, particularly as packing materials for High Performance Liquid Chromatography (HPLC). A method for the preparation of chromatographic support material is also disclosed which utilizes low pressure.

What is claimed is: 
     
       1. A .Iadd.porous .Iaddend.zirconium oxide spherule which has a diameter of about 1-500 microns and having a surface which is substantially covered by a carbon cladding. .[.2. The carbon-clad zirconium oxide spherule of claim 
     
     
        1 which is porous..]. 3. The carbon-clad zirconium oxide spherule of claim .[.2.]. .Iadd.1 .Iaddend.which has a surface area of about 5-300 m 2   
     
     
        /g. 4. The carbon-clad zirconium oxide spherule of claim .[.2.]. .Iadd.1 
     
     
        .Iaddend.which has a pore diameter of about 20-5000 Å. 5. A packing material useful as a stationary phase in a liquid chromatography column, comprising a plurality of the carbon-clad zirconium oxide particles of 
     
     
        claim 1. 6. A packing material useful as a stationary phase in a gas chromatography column, comprising a plurality of the carbon-clad zirconium 
     
     
        oxide particles of claim 1. 7. A packing material useful as a stationary phase in a supercritical fluid chromatography column, comprising a 
     
     
        plurality of the carbon-clad zirconium oxide particles of claim 1. 8. Carbon-clad inorganic oxide spherules which are prepared by a process comprising the steps of: (a) placing a plurality of porous inorganic oxide spherules having a surface, a diameter of about 1-500 microns, a surface area of about 5-300 m 2  /g and a pore diameter of about 20-5000 Å within a reaction chamber;   (b) elevating the temperature of the reaction chamber and reducing the pressure of the reaction chamber; and   (c) introducing a vapor comprising carbon into the reaction chamber so as to thermally decompose the vapor and deposit a cladding of the carbon onto the porous spherules, substantially covering the surface of the spherules.   
     
     
        . A porous zirconium oxide particle which has a core ZrO 2  particle having a pore diameter from about 20-5000 Angstroms having a surface which 
     
     
        is substantially covered by a carbon cladding. 10. The porous zirconium oxide particle of claim 9 comprising a core ZrO 2  particle having a surface area of about 5-300 m 2  /g.