Ex Parte Nedez et al - Page 7

                Appeal 2007-3383                                                                             
                Application 10/452,939                                                                       
                      We have considered, and are unpersuaded by, Appellants’ arguments                      
                and the evidence contained in the Kasztelan Declaration for the reasons                      
                below.                                                                                       
                      Tellier discloses that a weak point in the use of catalysts in the Claus               
                process for recovering sulphur is that the catalyst is very sensitive to oxygen              
                in the gas to be processed (Tellier, col. 1, ll. 37-47).  Tellier discloses the              
                following two embodiments to address the presence of oxygen: (1)                             
                modifying the Claus reactors where the sulphur is formed by replacing part                   
                of the traditional catalyst at the reactor inlet by an oxide catalyst containing             
                transition metals, or (2) preceding the traditional Claus reactors with a                    
                deoxidation reactor charged with a catalyst containing a transition metal                    
                compound (Tellier, col. 2, ll. 12-29).  Tellier discloses that the Claus process             
                generally uses several converters (i.e., reactors) in series (Tellier, col. 1,               
                ll. 19-21).  Tellier further claims “at least one catalytic reaction zone [i.e.,             
                reactor] containing a deoxidation catalyst and a Claus oxide catalyst”                       
                (Tellier, claim 1).                                                                          
                      Burmaster discloses that it is known that Claus installations are                      
                susceptible to catalyst fouling and deactivation caused by hydrocarbons,                     
                especially aromatic hydrocarbons like benzene, toluene and xylenes                           
                (Burmaster, col. 3, ll. 4-26).                                                               
                      Michel, like Tellier, discloses that it is known that the Claus reaction               
                generally includes a series of catalytic stages (Michel, col. 1, ll. 35-45).                 
                      Based on these disclosures, the applied prior art would have provided                  
                motivation for combining Burmaster’s disclosure to decrease the amount of                    
                aromatic hydrocarbons in the feed gas and Michel’s use of a series of                        
                multiple stages as is known in the Claus process with Tellier’s method of                    

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