Process for converting methanol to hydrocarbons suitable for use as gasoline or blendstock
The present application relates to a process for production of hydrocarbons comprising the steps of converting a feed stream comprising alcohols, ethers or mixtures hereof over a metal-containing zeolite based catalyst, active in dehydrogenation of hydrocarbons, in a conversion step thereby obtaining a conversion effluent, separating said effluent to obtain an aqueous process condensate stream, a liquid hydrocarbon stream and a gaseous stream, removing part of the hydrogen formed in the conversion step, and recycling at least part of the gaseous and/or liquid hydrocarbon stream to the conversion step.
1. A process for production of a hydrocarbon product suitable for use as gasoline or as a blendstock, said process comprising:
converting a feed stream comprising alcohols, ethers or mixtures thereof over a metal-containing zeolite based catalyst, active in dehydrogenation of hydrocarbons, in a conversion step thereby obtaining a conversion effluent,
separating said effluent to obtain an aqueous process condensate stream, a liquid hydrocarbon stream and a gaseous stream,
removing H 2 from at least part of the effluent thereby obtaining at least one at least partially H 2 depleted recycle stream, wherein removing H 2 is via a selective membrane, a selective oxidation step and/or a step wherein a hydrogen scavenger is converted into methanol or water in the presence of H 2 and a hydrogenation catalyst, and
recycling the at least one at least partially H 2 depleted recycle stream to the conversion step.
2. The process according to claim 1 , wherein at least part of the gaseous phase is recycled to the conversion step.
3. The process according to claim 1 , wherein the conversion step takes place in two or more consecutive reactors.
4. The process according to claim 1 , wherein the at least part of the recycle stream or recycle streams is returned to one or more points upstream the conversion step.
5. The process according to claim 1 , comprising a step regulating the H 2 content in the at least partly H 2 depleted recycle stream.
6. The process according to claim 1 , wherein the zeolite based catalyst is a single bifunctional catalyst catalysing both methanol to hydrocarbons and dehydrogenation.
7. The process according to claim 1 , wherein the zeolite based catalyst comprises a mixture of two or more catalysts which in combination catalyse both methanol to hydrocarbons and dehydrogenation reactions.
8. The process according to claim 1 , wherein the zeolite based catalyst comprises a metal and/or metal oxide and a zeolite.
9. The process according to claim 1 , wherein catalyst comprises a zeolite and a metal selected from the group consisting of Zn, Ga, In, Mo, Ag, P, Ge, Sn, Pd and Pt.
10. The process according to claim 1 , wherein the process is carried out in one or more fixed bed reactors.
11. The process according to claim 1 , wherein the process is carried out in one or more fluid bed reactors.
12. The process according to claim 1 , wherein the dehydrogenation catalyst is arranged as a top and/or bottom layer in the conversion reactor and/or in one or more separate dehydrogenation reactors.
13. A plant comprising:
means for supplying a feed stream comprising methanol, dimethyl ether or mixtures thereof
a conversion reactor
a separator for separating a conversion effluent into a gaseous recycle stream, process condensate and a liquid product,
means for removing H 2 from at least part of the effluent thereby obtaining at least one at least partially H 2 depleted recycle stream, and
means for recycling the at least partially H 2 depleted recycle stream,
wherein the means for removing H 2 from at least part of the effluent obtaining at least one at least partly H 2 depleted recycle stream is a selective membrane, a selective oxidation step and/or a step wherein a hydrogen scavenger is converted into methanol or water in the presence of H 2 and a hydrogenation catalyst.
14. A plant comprising:
means for supplying a feed stream comprising methanol, dimethyl ether or mixtures thereof
a conversion reactor
a separator for separating a conversion effluent into a gaseous recycle stream, process condensate and a liquid product,
means for removing H 2 from at least part of the effluent thereby obtaining at least one at least partially H 2 depleted recycle stream, and
means for recycling the at least partially H 2 depleted recycle stream,
wherein the means for removing H 2 from at least part of the effluent obtaining at least one at least partly H 2 depleted recycle stream comprises means for separating the liquid hydrocarbon stream into at least a product phase and one or more lower- and/or higher-boiling phases and means for recycling at least one of said lower- and/or higher-boiling phases as the at least partly H 2 depleted recycle stream.
15. Product obtained by the process according to claim 1 .
16. Gasoline obtained by the process according to claim 1 .
17. Reformate blendstock obtained by the process according to claim 1 .
18. High octane gasoline blendstock obtained by the process according to claim 1 .
19. A process for production of a hydrocarbon product suitable for use as gasoline or as a blendstock, said process comprising:
converting a feed stream comprising alcohols, ethers or mixtures thereof over a metal-containing zeolite based catalyst, active in dehydrogenation of hydrocarbons, in a conversion step thereby obtaining a conversion effluent,
separating said effluent to obtain an aqueous process condensate stream, a liquid hydrocarbon stream and a gaseous stream,
removing H 2 from at least part of the effluent thereby obtaining at least one at least partially H 2 depleted recycle stream, wherein removing H 2 is via separating the liquid hydrocarbon stream into at least a product phase and one or more lower- and/or higher-boiling phases and recycling at least one of said lower- and/or higher-boiling phases as the at least partly H 2 depleted recycle, and
recycling the at least one at least partially H 2 depleted recycle stream to the conversion step.
20. The process according to claim 19 , wherein the feed stream comprises methanol, dimethyl ether or mixtures thereof.
21. The process according to claim 19 , wherein the liquid hydrocarbon stream and/or product phase comprises raw gasoline, stabilized gasoline or gasoline with an aromatics content below 40%, a hydrocarbon product suitable as blend stock.
22. The process according to claim 19 , wherein the liquid hydrocarbon stream and/or product phase has a durene content below 6%.
23. The process according to claim 19 , wherein the hydrocarbon product is a high octane gasoline blendstock.
24. The plant of claim 13 , wherein the means for removing H 2 from at least part of the effluent obtaining at least one at least partly H 2 depleted recycle stream is a selective membrane.
25. The plant of claim 13 , wherein the means for removing H 2 from at least part of the effluent obtaining at least one at least partly H 2 depleted recycle stream is a selective oxidation step.
26. The plant of claim 13 , wherein the means for removing H 2 from at least part of the effluent obtaining at least one at least partly H 2 depleted recycle stream is a step wherein a hydrogen scavenger is converted into methanol or water in the presence of H 2 and a hydrogenation catalyst.
27. The process according to claim 1 , wherein the feed stream comprises methanol, dimethyl ether or mixtures thereof.
28. The process of claim 1 , wherein removing H 2 is via a selective membrane.
29. The process of claim 1 , wherein removing H 2 is via a selective oxidation step.
30. The process of claim 1 , wherein removing H 2 is via a step wherein a hydrogen scavenger is converted into methanol or water in the presence of H 2 and a hydrogenation catalyst.