Ex parte KETCHAM et al. - Page 7

                Appeal No. 1997-0448                                                                                                     
                Application No. 08/327,980                                                                                               

                filtering the resultant acid aqueous slurry to separate the insoluble molybdenum trioxide product, which                 

                also contains unreacted molybdenum disulfide and any other solid contaminating material, e.g., silica,                   
                from the filtrate which contains some dissolved molybdenum sulfate;  (C) transferring the filtrate to a5                                              

                neutralizer wherein a caustic is added to precipitate dissolved molybdenum trioxide which is recovered                   
                by filtration;  (D)(1) contacting the insoluble molybdenum trioxide product with aqueous ammonium6                                                                                                           

                hydroxide, thereby producing soluble ammonium molybdate; (D)(2) filtering the ammonium molybdate                         
                                                    7                                                                  8              
                from residual solid contaminants;  (D)(3) concentrating the ammonium molybdate in a crystallizer;  and                   

                (D)(4) calcining to produce ammonium gas which is recycled back to aqueous ammonium hydroxide,                           
                thereby yielding high purity molybdenum trioxide.   The9                                                                  

                residual solid contaminants of (D)(2) is preferably accumulated and treated as in steps (A) through                      

                (D)(2) above, with the corresponding filtrate containing ammonium molybdate being combined with the                      
                filtrate of step (D)(2) above.10                                                                                         

                        5See Barry, col. 4, lines 61-75.                                                                                 
                        6See Barry, col. 5, lines 1-8.                                                                                   
                        7See Barry, col. 5, lines 22-40.                                                                                 
                        8See Barry, col. 5, lines 41-43.                                                                                 
                        9See Barry, col. 5, lines 43-50.                                                                                 
                        10See Barry, col. 5, line 51 - col. 6, line 3.                                                                   
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