Treatment of air to a catalyst regenerator to maintain catalyst activity

Abstract

The invention relates to a conversion process for making olefin(s) using a molecular sieve catalyst composition. More specifically, the invention is directed to a process for converting a feedstock comprising an oxygenate in the presence of a molecular sieve catalyst composition, wherein the air feed to the catalyst regenerator is free of or substantially free of metal salts.

1 . A process of regenerating a molecular sieve catalyst comprising: 
 a) introducing a spent molecular sieve catalyst into a regeneration vessel;    b) introducing a flow of gas into said regeneration vessel, wherein said gas comprises about 0 to 100 ppb sodium; and    c) heating said molecular sieve catalyst for a sufficient period of time and at a sufficient temperature to regenerate said molecular sieve catalyst.    
   
   
       2 . The process of  claim 1  wherein said gas comprises about 10 to 50 ppb sodium.  
   
   
       3 . The process of  claim 1  wherein said gas comprises about 20 to 40 ppb sodium.  
   
   
       4 . The process of  claim 1  wherein said gas comprises less than 30 ppb sodium.  
   
   
       5 . The process of  claim 1  wherein said gas is subjected to a purification step prior to entering said regeneration vessel.  
   
   
       6 . The process of  claim 1  wherein said purification step comprising cooling said gas to condense and remove impurities including water and said sodium and then sending a purified gas flow to said regeneration vessel.  
   
   
       7 . The process of  claim 1  wherein said gas is selected from the group consisting of oxygen, O 3 , SO 3 , N 2 O, NO, NO 2 , N 2 O 5 , air, air diluted with nitrogen or carbon dioxide, oxygen and water carbon monoxide and hydrogen.  
   
   
       8 . The process of  claim 7  wherein said gas is air.  
   
   
       9 . The process of  claim 1  wherein said purification step comprises passing said gas through an adsorbent bed to remove impurities including water and salts followed by sending a resulting purified gas flow to said regeneration vessel.  
   
   
       10 . The process of  claim 1  wherein the feedstock comprises an oxygenate.  
   
   
       11 . The process of  claim 1  wherein the feedstock comprises methanol.  
   
   
       12 . The process of  claim 5  wherein prior to purification said gas contains at least one lithium, sodium, or potassium salt.  
   
   
       13 . The process of  claim 12  wherein prior to purification said gas contains at least one halide salt of lithium, sodium, or potassium.  
   
   
       14 . The process of  claim 13  wherein prior to purification said gas contains at least one chloride salt of lithium, sodium, or potassium.  
   
   
       15 . The process of  claim 14  wherein prior to purification said gas contains sodium chloride.  
   
   
       16 . The process of  claim 1  further comprising the step of converting the olefin to polyolefin.