Desulphurization of hydrocarbons using oxidative and hydro-treatments

Claim 1

A PROCESS FOR THE DESULPHURIZATION OF A PETROLEUM FRACTION CONTAINING AT LEAST A PROPORTION OF MATERIAL BOILING ABOVE 250*C. AND HAVING AT LEAST 1% WEIGHT OF SULPHUR, THE SULPHUR BEING PRESENT IN SAID FRACTION IN THE FORM OF SULPHUR-CONTAINING COMPOUNDS OF HIGH MOLECULAR WEIGHT, SAID PROCESS COMPRISING: TREATING SAID FRACTION IN SEPARATE AND SUCCESSIVE STAGES, ONE STAGE COMPRISING A TWOSTEP OXIDATIVE AND THERMAL DESULPHURIZATION STAGE AND THE OTHER STAGE COMPRISING A HYDROCATALYTIC DESULPHURIZATION STAGE; SAID TWO-STEP OXIDATIVE AND THERMAL DESULPHURIZATION STAGE COMPRISING CONTACTING THE FRACTION WITH AN OXIDIZING AGENT AT A TEMPERATURE WITHIN THE RANGE 80*C.180*C. USING AN AMOUNT OF OXIDIZING AGENT CORRESPONDING TO BETWEEN 1 AND 6 ACTIVE OXYGEN ATOMS PER ATOM OF SULPHUR IN THE FRACTION, AND FOR A PERIOD OF TIME OF 1/2 TO 20 HOURS, TO SELECTIVELY OXIDIZE THE SULPHUR-CONTAINING COMPOUNDS OF HIGH MOLECULAR WEIGHT, SUBJECTING THE OXIDIZED PRODUCTO TO A THERMAL DECOMPOSITION TREATMENT AT A TEMPERATURE IN THE RANGE ABOUNT 200*C.-400*C. FOR A PERIOD OF TIME SUFFICIENT TO DECOMPOSE THE OXIDIZED SULPHUR COMPOUND AND LIBERATE THE SULPHUR AS A SULPHUROUS GAS, AND REMOVING THE GSEOUS DECOMPOSITION PRODUCTS FROM THE PRODUCT OF SAID THERMAL DECOMPOSITION TREATMENT; AND SAID HYDROCATALYTIC DESULPHURIZATION STAGE COMPRISING CONTACTING THE FRACTION WITH A DESULPPHURIZATION CATALYST IN THE PRESENCE OF HYDROGEN AT A TEMPERATURE WITHIN THE RANGE 500*F.-900*F. AND A PRESSURE WITHIN THE RANGE 100 TO 2500 P.S.I.G.