Dual bed process using two different catalysts for selective hydrogenation of acetylene and dienes

A selective hydrogenation method comprising:

• contacting in the presence of hydrogen a feedstock comprising a compound selected from the group consisting of less than 5% acetylene and at least 50% ethylene thereof, where the contacting further comprises contacting the feedstock with a low oligomers selectivity first hydrogenation catalyst in a first reaction zone to produce a first product stream, where the oligomers selectivity of the first hydrogenation catalyst is at least 30% lower than the oligomers selectivity of the second hydrogenation catalyst in the second reaction zone, where the hydrogenation conditions of the first reaction zone include a temperature range of from 30 to 150° C., a pressure range of from 100 to 500 psig (690 to 3400 kPa), a GHSV of from 1000 to 10,000;
• and a H2/C2H2 molar feed ratio from 0.5 to 20;
• and
• contacting the first product stream in a second reaction zone having an inlet and an outlet, where the second reaction zone is at least partially filled with a second hydrogenation catalyst beginning from the outlet forward to produce a second product stream, where the second hydrogenation catalyst includes a metal selected from the group consisting of palladium, nickel and mixtures thereof, and where the hydrogenation conditions of the second reactor zone include a temperature range of from 30 to 150° C., a pressure range of from 100 to 500 psig (690 to 3400 kPa) and a GHSV of from 1000 to 10,000, and a H2/C2H2 molar feed ratio from 0.5 to 20.

A selective hydrogenation method comprising:

• contacting in the presence of hydrogen a feedstock comprising a compound selected from the group consisting of less than 1% acetylene and at least 20% ethylene thereof, where the contacting further comprises contacting the feedstock with a non-palladium, low oligomers selectivity first hydrogenation catalyst in a first reaction zone to produce a first product stream, where the oligomers selectivity of the first hydrogenation catalyst is at least 30% lower than the oligomers selectivity of the second hydrogenation catalyst in the second reaction zone, where the hydrogenation conditions of the first reaction zone include a temperature range of from 30 to 150° C., a pressure range of from 100 to 500 psig (690 to 3400 kPa), a GHSV of from 5000 to 20,000;
• and a H2 partial pressure from 25 psig to 175 psig (170 to 1200 kPa);
• and
• contacting the first product stream in a second reaction zone having an inlet and an outlet, where the second reaction zone is at least partially filled with a second hydrogenation catalyst beginning from the outlet forward to produce a second product stream, where the second hydrogenation catalyst includes a metal selected from the group consisting of palladium, nickel and mixtures thereof, and where the hydrogenation conditions of the second reaction zone include a temperature range of from 30 to 150° C., a pressure range of from 100 to 500 psig (690 to 3400 kPa), a GHSV of from 5000 to 20,000, and a H2 partial pressure from 25 psig to 175 psig (170 to 1200 kPa).

A selective hydrogenation method comprising:

• contacting in the presence of hydrogen a feedstock comprising a compound selected from the group consisting of at least 80-85% propylene and less than 10% methyl acetylene or propadiene thereof, where the contacting further comprises contacting the feedstock with a non-palladium, low oligomers selectivity first hydrogenation catalyst in a first reaction zone to produce a first product stream, where the oligomers selectivity of the first hydrogenation catalyst is at least 30% lower than the oligomers selectivity of the second hydrogenation catalyst in the second reaction zone, where the hydrogenation conditions of the first reaction zone can comprise include either (a) liquid phase operation, consisting of an inlet operating temperature from 20 to 100° C., a pressure range from 150 psig to 600 psig (1000 to 4100 kPa), a LHSV from 0.1 to 100, and a H2/C2H2 molar feed ratio from 0.5 to 20 or (b) vapor phase operation, consisting zone include an inlet operating temperature from 20 to 600° C., a pressure range from 150 psig to 600 psig (1000 to 4100 kPa), a GHSV from 100 to 20,000, and a H2/C2H2 molar feed ratio from 0.5 to 20;
• and
• contacting the first product stream in a second reaction zone having an inlet and an outlet, where the second reaction zone is at least partially filled with a second hydrogenation catalyst beginning from the outlet forward to produce a second product stream, where the second hydrogenation catalyst includes a metal selected from the group consisting of palladium, nickel and mixtures thereof, and where the hydrogenation conditions of the second reaction zone include either (a) liquid phase operation, consisting of an inlet operating temperature from 20 to 100° C., a pressure range from 150 psig to 600 psig (1000 to 4100 kPa), a LHSV from 0.1 to 100, and a H2/C2H2 molar feed ratio from 0.5 to 20 or (b) vapor phase operation, consisting zone include an inlet operating temperature from 20 to 600° C., a pressure range from 150 psig to 600 psig (1000 to 4100 kPa), a GHSV from 100 to 20,000, and a H2/C2H2 molar feed ratio from 0.5 to 20.

A selective hydrogenation method comprising:

• contacting in the presence of hydrogen a feedstock comprising a compound selected from the group consisting of at least 90% butylene and greater than 0.2% butadiene thereof, where the contacting further comprises contacting the feedstock with a low oligomers selectivity first hydrogenation catalyst in a first reaction zone to produce a first product stream, where the oligomers selectivity of the first hydrogenation catalyst is at least 30% lower than the oligomers selectivity of the second hydrogenation catalyst in the second reaction zone, where the hydrogenation conditions of the first reaction zone include either (a) liquid phase operation, consisting of an inlet operating temperature from 20 to 100° C., a pressure range from 150 psig to 600 psig (1000 to 4100 psig), a LHSV from 0.1 to 100, and a H2/C2H2 molar feed ratio from 0.5 to 20 or (b) vapor phase operation, consisting zone include an inlet operating temperature from 20 to 600° C., a pressure range from 150 psig to 600 psig (1000 to 4100 psig), a GHSV from 100 to 20,000, and a H2/C2H2 molar feed ratio from 0.5 to 20;
• and
• contacting the first product stream in a second reaction zone having an inlet and an outlet, where the second reaction zone is at least partially filled with a second hydrogenation catalyst beginning from the outlet forward to produce a second product stream, where the second hydrogenation catalyst includes a metal selected from the group consisting of palladium, nickel and mixtures thereof, and where the hydrogenation conditions of the second reaction zone include either (a) liquid phase operation, consisting of an inlet operating temperature from 20 to 120° C., a pressure range from 200 psig to 600 psig (1400 to 4100 psig), a LHSV from 0.1 to 100, and a H2/C2H2 molar feed ratio may range from 0.5 to 20, or (b) vapor phase operation, consisting zone include an inlet operating temperature from 20 to 600° C., a pressure range from 150 psig to 600 psig (1000 to 4100 psig), a GHSV from 100 to 20,000, and a H2/C2H2 molar feed ratio from 0.5 to 20.