Conversion of light naphtha to enhanced value products in an integrated two-zone reactor process

1. An integrated process for conversion of a hydrocarbon stream comprising light naphtha to enhanced value products, the process comprising:

(i) providing the hydrocarbon stream comprising light naphtha to a first reactor;

(ii) passing the hydrocarbon stream through the first reactor, the first reactor being a catalytic bed reactor with a dual-function catalyst disposed therein to simultaneously reform light naphtha to BTEX and crack light naphtha to ethane, propane, and butanes, where the dual-function catalyst comprises a nano ZSM-5 zeolite coated with amorphous silica or silica-alumina only on external pores of the nano ZSM-5 zeolite and without noble metal loading;

(iii) passing an effluent of the first reactor to a gas-liquid separating unit to generate a liquid stream comprising the BTEX and a gas stream comprising the ethane, propane, and butanes;

(iv) passing the gas stream to a gas separator unit to remove hydrogen gas and methane from the gas stream and generate an enhanced gas stream comprising an increased concentration of ethane, propane, and butanes; and

(v) passing the enhanced gas stream through a second reactor, the second reactor being a pyrolysis unit operated at steam cracking conditions to convert the ethane, propane, and butanes of the enhanced gas stream to light olefins including ethylene, propylene, and butenes;

wherein the integrated process does not include passage of a process stream to a separate and independent hydrocracking unit to crack light alkanes in the hydrocarbon stream to smaller alkanes.

2. The integrated process of claim 1 , where the nano ZSM-5 zeolite coated with amorphous silica or silica-alumina comprises 1 to 20 weight percent of the amorphous silica or silica-alumina.

3. The integrated process of claim 1 , where the first reactor is pressurized with nitrogen gas to a pressure of 1 to 50 bar at a space velocity of 0.1 to 100 h −1 .

4. The integrated process of claim 1 , where the integrated process further comprises providing the hydrocarbon stream to a MEROX unit to remove organic sulfur components from the hydrocarbon stream and generate a MEROX sweetened hydrocarbon stream prior to passing the MEROX sweetened hydrocarbon stream through the first reactor.

5. The integrated process of claim 1 , where the integrated process further comprises passing the gas stream from gas-liquid separating unit through a gas scrubber unit to remove hydrogen sulfide from the gas stream and generate a sweetened gas stream prior to passing the sweetened gas stream to the gas separator unit.

6. The integrated process of claim 1 , where the integrated process further comprises providing the hydrocarbon stream to a hydrotreater unit operating to convert organic sulfur components from the hydrocarbon stream to hydrogen sulfide and generate a hydrotreated hydrocarbon stream; and

further passing the hydrotreated hydrocarbon stream through a separator unit to remove the generated hydrogen sulfide and hydrogen gas from the hydrotreated hydrocarbon stream and generate a hydrotreated sweetened hydrocarbon stream prior to passing the hydrotreated sweetened hydrocarbon stream through the first reactor.

7. The integrated process of claim 1 , where the hydrocarbon stream comprises a boiling point of 90 to 315° F.

8. The integrated process of claim 1 , where the first reactor operates at a reaction temperature of 400 to 700° C.

9. The integrated process of claim 1 , where the second reactor operates at a cracking temperature of 750 to 900° C.

10. The integrated process of claim 1 , where the second reactor operates with a steam to hydrocarbon ratio of 0.1:1 to 0.6:1.

11. The integrated process of claim 1 , where the nano ZSM-5 zeolite coated with amorphous silica or silica-alumina comprises 3 to 7 weight percent of the amorphous silica or silica-alumina.