GB1504586A - Process for the catalytic hydrodesulphurisation of vanadium- and nickelcontaining residual hydrocarbon oils - Google Patents

Abstract

1504586 Hydrodesulphurization of heavy oils SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ BV 13 March 1975 [11 April 1974] 10508/75 Heading C5E In a process for the catalytic hydrodesulphurization of vanadium- and nickel-containing residual hydrocarbon oils without catalyst replenishment, the hydrocarbon oil is consecutively contacted with a catalyst I and a catalyst II which satisfy the requirements: (a) each of the individual catalysts of which the combination of catalyst I and catalyst II is composed has a total pore volume in excess of 0À30 ml./g. of which less than 10% is present as pores having a diameter in excess of 100 nm., (b) catalyst II has a specific average pore diameter (p) and a specific average particle diameter (d) such that the quotient p/(d)<SP>0À9</SP> of catalyst II satisfies the requirement where P H2 is the hydrogen partial pressure applied, (c) when the combination of catalyst I and catalyst II is composed of two catalysts, catalyst I has a p and d such that the quotient p/(d)<SP>0.9</SP> of catalyst I satisfies the requirement while when the combination of catalyst I and catalyst II is composed of more than two catalysts, the above requirement in respect of [p/(d)<SP>0À9</SP>]cat.I applies to the average p/(d)<SP>0À9</SP> of catalyst I determined as the weight average of the values of p/(d)<SP>0À9</SP> of each of the individual catalysts of which catalyst I is composed, (d) the percentage of the total catalyst volume which is taken up by catalyst II is between 10 and 90% and satisfies the requirement: Sf representing the sulphur content of the feed and Sp the sulphur content of the desulphurized product, and (e) when the combination of catalyst I and catalyst II is composed of more than two catalysts, each of the individual catalysts of which catalyst I is composed has a p and d such that the quotient p/(d)<SP>0À9</SP> of each of these catalysts is greater than [p/(d)<SP>0À9</SP>]cat.II, p being in nm., d in mm., P H2 in bar and Sp and Sf in weight per cent. The designation catalyst II is defined as being the second catalyst when a combination of two catalysts is used and as being the final catalyst when using a combination of more than two catalysts, the designation catalyst I being defined as being the first catalyst when two catalysts are used and all but the last catalyst when more than two are used. The catalysts used preferably contain 0À5 to 20 parts by weight of nickel and/or cobalt and 2À5 to 60 parts by weight of molybdenum and/or tungsten per 100 parts by weight of carrier, the metals being present on the carrier in metallic form or in the form of their oxides or sulphides, suitable carriers being the oxides of elements of Groups II, III and IV of the periodic system, e.g. silica, alumina, magnesia, zirconia and mixtures thereof.