Flexible light olefins production

An integrated process for the selective production of olefins from hydrocarbons comprising:

• (a) cracking a first hydrocarbon feedstock in a deep catalytic cracking process comprising contacting said first hydrocarbon feedstock with a solid, acidic catalyst selected from the group consisting of pentasil shape selective molecular sieves, ultrastable hydrogen Y sieves and a mixture of ultrastable hydrogen Y sieves and pentasil shape selective molecular sieves, in a fluidized or moving bed or dense phase transfer line reactor, in the presence of steam at a temperature in the range of from about 500.degree. C. to about 650.degree. C. and a pressure in the range of from about 1.5.times.10.sup.5 to about 3.0.times.10.sup.5 Pa with a weight hourly space velocity of from about 0.2 to about 20 hr.sup.-1, a catalyst-to-feedstock weight ratio of from about 2 to about 12, and a steam-to-feedstock ratio of from about 0.01 to about 2:1 by weight to produce a first olefin-containing effluent;
• (b) cracking a second hydrocarbon feedstock in a non-catalytic steam cracking process comprising thermally cracking said second hydrocarbon feedstock in the presence of steam in a radiant zone of a thermal cracking furnace wherein the mixture of said second hydrocarbon feedstock and steam is heated to an outlet temperature of from about 1500.degree. F. to about 1650.degree. F. and cracked in said radiant zone to produce said second olefin-containing effluent;
• (c) combining said first olefin-containing effluent with said second olefin-containing effluent to produce a mixed olefin-containing effluent;
• (d) separating the mixed olefin-containing effluent in an olefins purification process comprising at least one fractionator into a plurality of component effluent streams comprising one or more of an ethane-rich stream, a propane-rich stream, an ethylene-rich stream, a propylene-rich stream, a mixed C.sub.4 hydrocarbon-rich stream, a gasoline-rich stream, a diesel-rich stream and a fuel oil-rich stream;
• and
• (e) recycling at least a portion of one or more of said ethane-rich stream, propane-rich stream and/or mixed C.sub.4 mixed hydrocarbon-rich stream to said steam cracking step (b) as at least a portion of said second hydrocarbon feedstock.

An integrated process for the improved production of propylene from hydrocarbons which comprises:

• (a) cracking a first hydrocarbon feedstock in a deep catalytic cracking process comprising contacting said first hydrocarbon feedstock with a solid, acidic catalyst selected from the group consisting of pentasil shape selective molecular sieves, ultrastable hydrogen Y sieves and a mixture of ultrastable hydrogen Y sieves and pentasil shape selective molecular sieves in a fluidized or moving bed or dense phase transfer line reactor, in the presence of steam at a temperature in the range of from about 500.degree. C. to about 650.degree. C. and a pressure in the range of from about 1.5.times.10.sup.5 to about 3.0.times.10.sup.5 Pa with a weight hourly space velocity of from about 0.2 to about 20 hr.sup.-1, a catalyst-to feedstock ratio of from about 2 to about 12, and a steam-to-feedstock ratio of from about 0.01 to about 2:1 by weight to produce a first olefin-containing effluent;
• (b) cracking a second hydrocarbon feedstock in a non-catalytic steam cracking process comprising thermally cracking said second hydrocarbon feedstock in the presence of steam in a radiant zone of a thermal cracking furnace wherein the mixture of said second hydrocarbon feedstock and steam is heated to an outlet temperature of from about 1500.degree. F. to about 1650.degree. F. and cracked in said radiant zone to produce a second olefin-containing effluent;
• (c) combining said first olefin-containing effluent and said second olefin-containing effluent to produce a mixed olefin-containing effluent;
• (d) separating said mixed olefin-containing effluent in an olefins purification process comprising at least one fractionator into a plurality of component effluent streams comprising one or more of an ethane-rich stream, a propane-rich stream, an ethylene-rich stream, a propylene-rich stream, a mixed C.sub.4 hydrocarbon-rich stream, a gasoline-rich stream, a diesel-rich stream and a fuel oil-rich stream;
• (e) recycling one or more of at least a portion of said ethane-rich stream, said propane-rich stream, said mixed C.sub.4 hydrocarbon rich stream or said gasoline-rich stream to said steam cracking process (b) as at least a portion of said second hydrocarbon feedstock;
• (f) disproportionating at least a portion of the ethylene in said ethylene-rich stream with at least a portion of the normal butenes from said mixed C.sub.4 hydrocarbon-rich stream in the presence of a disproportionation catalyst at a temperature ranging from about 0.degree. to about 600.degree. C., a pressure ranging from about 0.1 to about 500 atmospheres, and with a contact time ranging from about 0.1 seconds to about 24 hours to produce a disproportionation effluent rich in propylene;
• (g) recycling said disproportionation effluent to said olefins purification process;
• and
• (h) recovering said propylene-rich stream from said olefins purification process.

An integrated process for the improved production of ethylene from hydrocarbons which comprises:

• (a) cracking a first hydrocarbon feedstock in a deep catalytic cracking process comprising contacting said first hydrocarbon feedstock with a solid, acidic catalyst selected from the group consisting of pentasil shape selective molecular sieves, ultrastable hydrogen Y sieves and a mixture of ultrastable hydrogen Y sieves and pentasil shape selective molecular sieves, in a fluidized or moving bed or dense phase transfer line reactor, in the presence of steam at a temperature in the range of from about 500.degree. C. to about 650.degree. C. and a pressure in the range of from about 1.5.times.10.sup.5 to about 3.0.times.10.sup.5 Pa with a weight hourly space velocity of from about 0.2 to about 20 hr.sup.-1, a catalyst-to-feedstock ratio of from about 2 to about 12, and a steam-to-feedstock ratio of from about 0.01 to about 2:1 by weight to produce a first olefin-containing effluent;
• (b) cracking a second hydrocarbon feedstock in a non-catalytic steam cracking process comprising thermally cracking said second hydrocarbon feedstock in the presence of steam in a radiant zone of a thermal cracking furnace wherein the mixture of said second hydrocarbon feedstock and steam is heated to an outlet temperature of from about 1500.degree. F. to about 1650.degree. F. and cracked in said radiant zone to produce a second olefin-containing effluent;
• (c) combining said first olefin-containing effluent and second olefin-containing effluent to produce a mixed olefin-containing effluent;
• (d) separating said mixed olefin-containing effluent in an olefins purification process comprising at least one fractionator into a plurality of component effluent streams comprising an ethane-rich stream, a propane-rich stream, an ethylene-rich stream, a propylene-rich stream, a C.sub.4 hydrocarbon-rich stream, a gasoline-rich stream, a diesel-rich stream and a fuel oil-rich stream;
• (e) recycling at least a portion of one or more of said ethane-rich stream, propane-rich stream, mixed C.sub.4 hydrocarbon-rich stream or said gasoline-rich stream to said steam cracking process (b) as at least a portion of said second hydrocarbon feedstock;
• (f) disproportionating at least a portion of the propylene in said propylene-rich stream in the presence of a disproportionation catalyst at a temperature ranging from about 0.degree. to about 600.degree. C., a pressure ranging from about 0.1 to about 500 atmospheres, and with a contact time ranging from about 0.1 seconds to about 24 hours to produce a disproportionation effluent rich in ethylene and butylenes;
• (g) recycling said disproportionation effluent to olefins purification process;
• and
• (h) recovering said ethylene-rich stream from said olefins purification process.

An integrated process for the selective production of methyl tertiary butyl ether from hydrocarbons comprising:

• (a) cracking a first hydrocarbon feedstock in a deep catalytic cracking process comprising contacting said heavy hydrocarbon feedstock with a solid, acidic catalyst selected from the group consisting of pentasil shape selective molecular sieves, ultrastable hydrogen Y sieves and a mixture of ultrastable hydrogen Y sieves and pentasil shape selective molecular sieves, in a fluidized or moving bed or dense phase transfer line reactor, in the presence of steam at a temperature in the range of from about 500.degree. C. to about 650.degree. C. and a pressure in the range of from about 1.5.times.10.sup.3 to about 3.0.times.10.sup.5 Pa with a weight hourly space velocity of from about 0.2 to about 20 hr.sup.-1, a catalyst-to-feedstock ratio of from about 2 to about 12, and a steam-to-feedstock ratio of from about 0.01 to about 2:1 by weight to produce a first olefin-containing effluent;
• (b) cracking a second hydrocarbon feedstock in a non-catalytic steam cracking process comprising thermally cracking said second hydrocarbon feedstock in the presence of steam in a radiant zone of a thermal cracking furnace wherein the mixture of said second hydrocarbon feedstock and steam is heated to an outlet temperature of from about 1500.degree. F. to about 1650.degree. F. and cracked in said radiant zone to produce a second olefin-containing effluent;
• (c) combining said first olefin-containing effluent and said second-olefin containing effluent to produce a mixed olefin-containing effluent;
• (d) introducing said mixed olefin-containing effluent into an olefin purification process comprising:
• (i) compressing said mixed olefin-containing effluent to a pressure ranging from about 350 to about 520 psig to produce a compressed olefin-containing stream;
• (ii) chilling the compressed olefin-containing stream to a temperature ranging from about -185.degree. F. to about -235.degree. F. to produce a chilled compressed olefin-containing stream;
• and
• (iii) separating the chilled compressed olefin-containing stream in at least one fractionator into a plurality of component effluent streams comprising at least one of an ethane-rich stream, a propane-rich stream, an ethylene-rich stream, a propylene-rich stream, a mixed C.sub.4 hydrocarbon-rich stream and a gasoline-rich stream;
• (e) recycling at least a portion of one or more of said ethane-rich stream, said propane-rich stream or said gasoline-rich stream to said steam cracking process (b) as at least a portion of said second hydrocarbon feedstock;
• (f) disproportionating at least a portion of the propylene in said propylene-rich stream in the presence of a disproportionation catalyst at a temperature ranging from about 0.degree. C. to about 600.degree. C., a pressure ranging from about 0.1 to about 500 atmospheres, and with a contact time ranging from about 0.1 seconds to about 24 hours to produce a disproportionation effluent rich in ethylene and normal butylenes;
• (g) recycling said disproportionation effluent to said olefin purification process;
• (h) passing said mixed C.sub.4 hydrocarbon-rich stream to a C.sub.4 hydrocarbon processing zone comprising:
• (1) hydroisomerizing said mixed C.sub.4 hydrocarbon-rich stream to catalytically convert substantially all of acetylenes and dienes in said C.sub.4 hydrocarbon-rich stream to butenes and catalytically converting at least a portion of the 1-butene in said C.sub.4 hydrocarbon-rich stream to 2-butenes;
• wherein said hydroisomerization is carried out at a temperature ranging from about 40.degree. C. to about 400.degree. C., a pressure ranging from about 1 to about 100 bar and a space velocity ranging from about 0.5 to about 2.0 kg hydrocarbon feed/kg catalyst hour in the presence of a hydroisomerization catalyst comprising at least one hydrogenating metal and a moderately acidic carrier;
• (2) reacting at least a portion of the isobutylene in said hydroisomerized C.sub.4 hydrocarbon-rich stream with methanol in a methyl tertiary butyl ether synthesis reactor in the presence of an acid type ion exchange resin catalyst to produce an ether synthesis product effluent stream rich in methyl tertiary butyl ether and a synthesis by-product effluent stream;
• (3) separating said synthesis by-product effluent stream in an extractive distillation tower in the presence of a solvent into a paraffin-rich stream substantially comprising C.sub.3 and lighter boiling hydrocarbons, isobutane and n-butane, and a C.sub.4 olefin-rich stream substantially comprising cis-2-butene, trans-2-butene and 1-butene;
• and
• (4) converting at least a portion of the normal butenes in said C.sub.4 olefin-rich effluent to isobutylene in the presence of an acidic skeletal isomerization catalyst at a pressure of about atmospheric pressure and a temperature ranging from about 600.degree. F. to about 1100.degree. F. to produce an isobutylene enriched effluent;
• (i) recycling said isobutylene enriched effluent either to said methyl tertiary butyl ether synthesis reactor, or to the hydroisomerization step;
• and
• (j) recovering said ether synthesis product effluent rich in methyl tertiary butyl ether.

An integrated process for the selective production of olefins from hydrocarbons comprising:

• (a) cracking a first hydrocarbon feedstock in a deep catalytic cracking process comprising contacting said heavy hydrocarbon feedstock with a solid, acidic catalyst selected from the group consisting of pentasil shape selective molecular sieves, ultrastable hydrogen Y sieves and a mixture of ultrastable hydrogen Y sieves and pentasil shape selective molecular sieves, in a fluidized or moving bed or dense phase transfer line reactor, in the presence of steam at a temperature in the range of from about 500.degree. C. to about 650.degree. C. and a pressure in the range of from about 1.5.times.10.sup.5 to about 3.0.times.10.sup.5 with a weight hourly space velocity of from about 0.2 to about 20 hr.sup.-1, a catalyst-to-feedstock ratio of from about 2 to about 12, and a steam-to-feedstock ratio of from about 0.01 to about 2:1 by weight to produce a first olefin-containing effluent;
• (b) cracking a second hydrocarbon feedstock in a non-catalytic thermal cracking process to produce a second olefin-containing effluent;
• (c) combining said first olefin-containing effluent with said second olefin-containing effluent to produce a mixed olefin-containing effluent for downstream processing;
• (d) recycling a portion of said mixed olefin-containing effluent to said non-catalytic cracking step (b) as at least a portion of said second hydrocarbon feedstock;
• and
• (e) recovering an effluent of selectively produced olefins from the mixed olefin-containing effluent.