Polymorph-enriched ETS-4

Abstract

ETS-4 crystalline titanium silicate is produced so as to be enriched in at least one polymorph thereof which contains channels which interpenetrate the crystal lattice in both the b- and c-directions. A process of producing such a polymorph and enriched ETS-4 titanium silicate comprises the addition of a wetting agent to the reaction mixture.

We claim:  
     
         1 . A synthetic ETS-4 titanium silicate containing greater than 5% of a polymorph phase characterized as having pores which interpenetrate the framework of the ETS-4 in the b- and c-directions.  
     
     
         2 . The synthetic ETS-4 titanium silicate of  claim 1 , wherein said pores in the c-direction include c-directed channels formed from 12-membered pores.  
     
     
         3 . The synthetic ETS-4 titanium silicate of  claim 1 , wherein said titanium silicate includes alkaline earth metal cations exchanged thereon.  
     
     
         4 . The synthetic ETS-4 titanium silicate of  claim 3 , wherein said alkaline earth metal cations include barium, calcium or strontium.  
     
     
         5 . The synthetic ETS-4 titanium silicate of  claim 1 , containing at least 20% of said polymorph.  
     
     
         6 . A synthetic ETS-4 titanium silicate, which comprises greater than 5% of at least one polymorph phase of ETS-4 which contains non-faulted channels which penetrate the ETS-4 framework in the c-direction.  
     
     
         7 . The synthetic ETS-4 titanium silicate of  claim 6 , comprising a mixture of two of said polymorphs, which contain channels which interpenetrate the framework of ETS-4 in the c-direction.  
     
     
         8 . The synthetic ETS-4 titanium silicate of  claim 6 , which is exchanged with alkaline earth metal cations.  
     
     
         9 . The synthetic ETS-4 titanium silicate of  claim 8 , wherein said alkaline earth metal cations include barium, calcium, or strontium.  
     
     
         10 . The synthetic ETS-4 titanium silicate of  claim 6  containing at least 20% of said at least one polymorph phase.  
     
     
         11 . A synthetic, crystalline titanium silicate having a composition in terms of mole ratios of oxides as follows: 
       1.0±0.25 M 2/n O:TiO 2 :Y SiO 2 :Z H 2 O 
       wherein M is at least one cation having a valence of n, Y is from 1.0 to 100, and Z is from 0 to 100 and characterized by an X-ray powder diffraction pattern having the lines and relative intensities set forth in Table I below:  
       
         
           
                 
                 
                 
               
                     
                   TABLE 1 
                 
                     
                     
                 
                     
                     
                 
                     
                   d-SPACING (ANGS.) 
                   I/I 0   
                 
                     
                     
                 
                     
                   11.65 ± 0.25  
                   S-VS 
                 
                     
                   6.95 ± 0.25 
                   S-VS 
                 
                     
                   5.28 ± 0.15 
                   M-S 
                 
                     
                   4.45 ± 0.15 
                   W-M 
                 
                     
                   2.98 ± 0.05 
                   VS 
                 
                     
                     
                 
                     
                   
                    
                   
                 
                     
                   
                    
                   
                 
                     
                   
                    
                   
                 
                     
                   
                    
                   
                 
                     
                   
                    
                   
                 
                     
                     
                 
             
                
                
                
                
                
               
               
                
                
                
                
                
                
                
                
                
                
                
                
               
            
           
         
       
       wherein said X-ray powder diffraction pattern has an additional line at a d-spacing greater than 11.65 Å of a relative intensity I/I 0  of W-M, and the ratio of peak heights of said additional line to said line at 11.65±0.25 Å is greater than 5%.  
     
     
         12 . The synthetic, titanium silicate of  claim 11 , wherein said additional line of said X-ray powder diffraction pattern is at a d-spacing of 12.5±0.25 Å.  
     
     
         13 . The synthetic, titanium silicate of  claim 11 , wherein said additional line of said X-ray powder diffraction pattern is at a d-spacing of 13.9±0.25 Å.  
     
     
         14 . The synthetic, titanium silicate of  claim 11  wherein the ration of peak heights of said additional line to said line at 11.65±0.25 Å is greater than 20%  
     
     
         15 . The synthetic ETS-4 titanium silicate of  claim 1 , which has been heat treated to reduce the pores in the b-direction to less than 4 Å and the pores in the c-direction to less than 6 Å.  
     
     
         16 . The synthetic ETS-4 titanium silicate of  claim 5 , which has been heat treated to reduce the channels in the c-direction to less than 6 Å in diameter.