Method for capturing mercaptans using a macro and mesoporous capture mass
Process for trapping mercaptans contained in a sulfur-containing hydrocarbon feedstock, in the presence of a trapping mass comprising an active phase based on at least one group VIII, IB or IIB metal, and a mesoporous or macroporous support, said trapping mass comprising a specific surface area of between 120 m 2 /g and 350 m 2 /g, and: the volume of mesopores with a diameter greater than or equal to 2 nm and less than 50 nm corresponds to between 40% and 70% by volume of the total pore volume of said trapping mass; the volume of macropores with a diameter greater than or equal to 50 nm corresponds to between 30% and 60% by volume of the total pore volume of said trapping mass.
1 . A process for trapping mercaptans contained in a sulfur-containing hydrocarbon feedstock, at a temperature of between 40° C. and 250° C., a pressure of between 0.2 MPa and 5 MPa, at an hourly space velocity, defined as the volume flow rate of feedstock at the inlet per volume of trapping mass, of between 0.1 h −1 and 50 h −1 , in the presence of a trapping mass comprising an active phase based on at least one group VIII, IB or IIB metal, and a support, said support being selected from the group consisting of alumina, silica, silica-alumina, and clays, said trapping mass having a specific surface area of between 120 m 2 /g and 350 m 2 /g, and wherein the traping mass is both mesoporous and macroporous, and wherein:
the volume of mesopores with a diameter greater than or equal to 2 nm and less than 50 nm corresponds to between 40% and 70% by volume of the total pore volume of said trapping mass;
the volume of macropores with a diameter greater than or equal to 50 nm corresponds to between 30% and 60% by volume of the total pore volume of said trapping mass.
2 . The process as claimed in claim 1 , wherein said trapping mass has a specific surface area of between 150 m 2 /g and 300 m 2 /g.
3 . The process as claimed in claim 1 , wherein the volume of mesopores with a diameter greater than or equal to 2 nm and less than 50 nm corresponds to between 45% and 65% by volume of the total pore volume of said trapping mass.
4 . The process as claimed in claim 1 , wherein the volume of macropores with a diameter greater than or equal to 50 nm corresponds to between 35% and 55% by volume of the total pore volume of said trapping mass.
5 . The process as claimed in claim 1 , wherein the content of group VIII, IB or IIB element is from 10% to 80% by weight relative to the total weight of the trapping mass.
6 . The process as claimed in claim 1 , wherein said group VIII, IB or IIB metal is nickel, copper or zinc.
7 . The process as claimed in claim 6 , wherein said metal is nickel.
8 . The process as claimed in claim 1 , wherein the content of aluminum and/or silicon elements in said trapping mass is between 5% and 45% by weight relative to the total weight of the trapping mass.
9 . The process as claimed in claim 1 , wherein said trapping mass has a total pore volume, measured by mercury porosimetry, of between 0.1 ml/g and 0.7 ml/g.
10 . The process as claimed in claim 1 , wherein said hydrocarbon feedstock is a feedstock that has been partially desulfurized by a catalytic hydrodesulfurization step.
11 . The process as claimed in claim 10 , wherein said hydrocarbon feedstock is a partially desulfurized catalytic cracking gasoline having a boiling point below 350° C. and containing between 5% and 60% by weight of olefins and less than 100 ppm by weight of sulfur relative to the total weight of said feedstock.