Process to prepare normal paraffins

Patent metadata

Field	Value
Publication number	US-10934492-B2
Application number	US-201716346799-A
Country	US
Kind code	B2
Filing date	Nov 2, 2017
Priority date	Nov 7, 2016
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

A process for preparing normal paraffins involves separating a Fischer-Tropsch product stream to obtain first gaseous and liquid hydrocarbon streams. The first gaseous hydrocarbon stream is cooled and separated to obtain a second liquid hydrocarbon stream and a third liquid hydrocarbon stream, which are hydrogenated. The hydrogenated liquid hydrocarbon stream is separated by distillation to obtain a hydrogenated normal paraffin fraction comprising 5 to 9 carbon atoms, a hydrogenated normal paraffin fraction comprising 10 to 13 carbon atoms, a hydrogenated normal paraffin fraction comprising 14 to 18 carbon atoms, and a hydrogenated normal paraffin fraction comprising 19 to 35 carbon atoms.

First claim

That which is claimed is:

1. A process to prepare normal paraffins, the process comprises the steps of:
(a) providing a volume of a Fischer-Tropsch product stream;
(b) separating the volume of the Fischer-Tropsch product stream to form a first gaseous hydrocarbon stream and a first liquid hydrocarbon stream;
(c) cooling and separating the first gaseous hydrocarbon stream in two or more steps to obtain a second liquid hydrocarbon stream and a third liquid hydrocarbon stream, wherein the second liquid hydrocarbon stream comprises heavier carbon atoms molecules than the third liquid hydrocarbon stream;
(d) subjecting at least one of the second liquid hydrocarbon stream and the third liquid hydrocarbon stream to a hydrogenation step, to form a hydrogenated liquid hydrocarbon stream;
(e) separating the hydrogenated liquid hydrocarbon stream using one or more atmospheric distillation(s), into the following fractions:
a hydrogenated normal paraffin fraction comprising 5 to 9 carbon atoms, a hydrogenated normal paraffin fraction comprising 10 to 13 carbon atoms, a hydrogenated normal paraffin fraction comprising 14 to 18 carbon atoms, and a hydrogenated normal paraffin fraction comprising 19 to 35 carbon atoms.

2. The process according to claim 1 , wherein the separating the volume of the Fischer-Tropsch product stream is performed at a temperature in a range of from 160 to 350° C. and at a pressure in a range of from 5 to 150 bar.

3. The process according to claim 1 , wherein the cooling and separating of the first gaseous hydrocarbon stream is performed at a temperature in a range of from 5 to 180° C. and at a pressure in a range of from 5 to 145 bar.

4. The process according to claim 1 , wherein the cooling and separating of the first gaseous hydrocarbon stream is performed in two steps.

5. The process according to claim 1 , wherein prior to the hydrogenation step, the second liquid hydrocarbon stream and the third liquid hydrocarbon stream are combined.

6. The process according claim 1 , wherein prior to the hydrogenation step, a fraction comprising 5 to 9 carbon atoms is separated from the second liquid hydrocarbon and the third liquid hydrocarbon stream by atmospheric distillation.

7. The process according to claim 1 , wherein the atmospheric distillation is performed at a temperature in the range of 200 to 400° C.

8. The process according to claim 1 ,
wherein between 45 and 60 wt. % of the hydrogenated liquid hydrocarbon stream comprises the hydrogenated normal paraffin fraction comprising 10 to 13 carbon atoms, and
wherein between 40 and 55 wt. % of the hydrogenated liquid hydrocarbon stream comprises the hydrogenated normal paraffin fraction comprising 14 to 17 carbon atoms.

9. The process according to claim 1 , wherein the hydrogenated normal paraffin fraction comprising 10 to 13 carbon atoms further comprises
10 to 11 wt. % of paraffins having 10 carbon atoms;
30 to 32 wt. % of paraffins having 11 carbon atoms;
30 to 32 wt. % of paraffins having 12 carbon atoms; and
23 to 26 wt. % of paraffins having 13 carbon atoms.

10. The process according to claim 1 , wherein the hydrogenated normal paraffin fraction comprising 14 to 18 carbon atoms further comprises:
25 to 27 wt. % of paraffins having 14 carbon atoms;
24 to 26 wt. % of paraffins having 15 carbon atoms;
22 to 23 wt. % of paraffins having 16 carbon atoms;
18 to 20 wt. % of paraffins having 17 carbon atoms; and
4 to 6 wt. % of paraffins having 18 carbon atoms.

11. The process according to claim 1 , wherein the volume of the Fischer-Tropsch product stream is at a temperature in a range of from 190 to 250° C.

12. The process according to claim 1 , wherein the atmospheric distillation is performed at a temperature in the range of 300 to 350° C.

13. The process according to claim 1 , wherein 49 wt. % of the hydrogenated liquid hydrocarbon stream comprises the hydrogenated normal paraffin fraction comprising 10 to 13 carbon atoms.

14. The process according to claim 1 , wherein 51 wt. % of the hydrogenated liquid hydrocarbon streams comprises the hydrogenated normal paraffin fraction comprising 14 to 17 carbon atoms.

Assignees

• Shell Oil Co

Inventors

• Bezemer Gerrit Leendert

Classifications

• C10G73/44

  in the presence of hydrogen or hydrogen-generating compounds · CPC title

• C10G73/36

  Recovery of petroleum waxes from other compositions containing oil in minor proportions, from concentrates or from residues; De-oiling, sweating · CPC title

• C10L2290/42

  Fischer-Tropsch steps · CPC title

• C10G49/22

  Separation of effluents · CPC title

• C10L2200/0492

  Fischer-Tropsch products · CPC title