Process for preparing hydrocarbon mixture exhibiting unique branching structure

Patent metadata

Field	Value
Publication number	US-11247948-B2
Application number	US-202117146198-A
Country	US
Kind code	B2
Filing date	Jan 11, 2021
Priority date	Sep 20, 2018
Publication date	Feb 15, 2022
Grant date	Feb 15, 2022

Abstract

Provided herein is a unique process that prepares a saturated hydrocarbon mixture with well-controlled structural characteristics that address the performance requirements driven by the stricter environmental and fuel economy regulations for automotive engine oils. The process allows for the branching characteristics of the hydrocarbon molecules to be controlled so as to consistently provide a composition that has a surprising CCS viscosity at −35° C. (ASTM D5329) and Noack volatility (ASTM D5800) relationship. The process comprises providing a specific olefinic feedstock, oligomerizing in the presence of a BF 3 catalyst, and hydroisomerizing in the presence of a noble-metal impregnated, 10-member ring zeolite catalyst.

First claim

That which is claimed is:

1. A process for preparing a base stock, comprising:
(i) providing an olefinic feedstock comprising C14 to C20 olefins which comprises less than 40 wt % branched olefins and greater than 40 wt % alpha olefins;
(ii) oligomerizing the olefinic feedstock using a boron trifluoride catalyst at a reaction temperature in a range of from 20-60° C., while controlling the reaction conditions to obtain an intermediate having a dimers fraction such that the dimers fraction of the intermediate when saturated without hydroisomerization results in a saturated dimer with a branching proximity of 27-35; and
(iii) hydroisomerizing at least a portion of the intermediate obtained from step (ii) using a metal impregnated one-dimensional, 10-member ring zeolite catalyst to achieve a C28+ product with BP/BI≥−0.6037*(Internal alkyl branching per molecule)+2.0 and on average 0.3 to 1.5 methyl branches on the fifth or greater position per molecule.

2. The process of claim 1 , wherein the olefinic feedstock comprises greater than 50 wt % alpha olefins.

3. The process of claim 2 , wherein the olefinic feedstock comprises less than 8 wt % branched olefins.

4. The process of claim 1 , wherein the olefinic feedstock comprises greater than 70 wt % alpha olefins.

5. The process of claim 1 , wherein the boron trifluoride catalyst used in the oligomerizing of (ii) further comprises an alcohol promoter, and an ester promoter.

6. The process of claim 1 , wherein the residence time for the oligomerization reaction ranges from 60-180 minutes.

7. The process of claim 2 , further comprising recovering the intermediate, removing unreacted monomer from the intermediate, and recovering a resulting intermediate prior to step (iii).

8. The process of claim 7 , wherein the unreacted monomer removed is recycled to the olefinic feedstock of step (i).

9. The process of claim 7 , further comprising hydrogenating the resulting intermediate to create a hydrogenated intermediate, the hydrogenated intermediate is then subjected to the hydroisomerization of step (iii); and
recovering a product from the hydroisomerization and separating product from the hydroisomerization into a fraction comprising greater than 95 wt % dimers having a maximum carbon number of 40, and a fraction comprising greater than 95 wt % trimers and higher oligomers having a minimum carbon number of 42.

10. The process of claim 7 , wherein the resulting intermediate is separated into a fraction comprising greater than 95 wt % dimers having a maximum carbon number of 40, and a fraction comprising greater than 95% trimers and higher oligomers having a minimum carbon number of 42.

11. The process of claim 10 , further comprising hydroisomerizing each of the fractions separately.

12. The process of claim 7 , wherein the resulting intermediate is further hydrogenated to create a hydrogenated intermediate, with the hydrogenated intermediate comprising dimers having a maximum carbon number of 40 and a branching proximity from 28-32.

13. The process of claim 2 , wherein the hydroisomerizing is conducted under a pressure of 100-800 psig; a temperature in a range of from 290-350° C., and a hydrogen flow rate of 500-3500 scf/bbl.

14. A process for preparing a base stock, comprising:
(i) providing an olefinic feedstock comprising less than 8 wt % branched monomeric olefins and greater than 50 wt % monomeric alpha olefins, with the monomeric olefins having a carbon number in the range of from C14-C20;
(ii) conducting an oligomerization reaction with the olefinic feedstock of (i) at a temperature in the range of from 20 to 60° C., over a BuOH and BuAc co-catalyst, with a reaction residence time of from 60-180 minutes, in a semi-batch or continuous stirred tank reactor, while controlling the reaction conditions to obtain an intermediate with a dimers fraction such that the dimers fraction of the intermediate when saturated without hydroisomerization results in a saturated dimer with a branching proximity of 27-35;
(iii) recovering the intermediate from the oligomerization reaction in step (ii), removing unreacted monomer by distillation, and recovering a resulting intermediate from the distillation;
(iv) hydrogenating the resulting intermediate recovered from the distillation in (iii);
(v) recovering a hydrogenation product from the hydrogenation in (iv) and hydroisomerizing the hydrogenation product over a metal impregnated, one-dimensional zeolite with a 10-member ring at a pressure in the range of from 100-800 psig; a temperature in the range of from 290-350° C.; and at a hydrogen flow rate of 500-3500 scf/bbl to produce a hydroisomerized product;
(vi) recycling the unreacted monomer removed in (iii) to the olefinic feedstock in (i); and
(vii) separating a dimers fraction and a trimers and higher oligomers fraction from the hydroisomerized product of step (v), with the dimers fraction comprising greater than or equal to 95 wt % dimers having a maximum carbon number of 40.

15. A process for preparing a base stock, comprising:
(i) providing an olefinic feedstock comprising less than 8 wt % branched monomeric olefins and greater than 50 wt % monomeric alpha olefins, with the monomeric olefins having a carbon number in the range of from C14-C20;
(ii) conducting an oligomerization reaction with the olefinic feedstock of (i) at a temperature in the range of from 20 to 60° C., over a BuOH and BuAc co-catalyst, with a reaction residence time of from 60-180 minutes, in a semi-batch or continuous stirred tank reactor, while controlling the reaction conditions to obtain an intermediate with a dimers fraction such that the dimers fraction of the intermediate when saturated without hydroisomerization results in a saturated dimer with a branching proximity of 27-35;
(iii) recovering the intermediate from the oligomerization reaction in step (ii), removing unreacted monomer by distillation;
(iv) recovering a bottoms product from the distillation in (iii) and hydroisomerizing the bottoms product over a metal impregnated, one-dimensional zeolite with a 10-member ring at a pressure in the range of from 100-800 psig; a temperature in the range of from 290-350° C.; and at a hydrogen flow rate of 500-3500 scf/bbl;
(v) recycling the unreacted monomer removed in (iii) to the olefinic feedstock in (i); and
(vi) recovering a hydroisomerization product from the hydroisomerization in (iv) and separating the hydroisomerization product into a dimer fraction comprising dimers having a carbon number in the range of from C28-C40, and a trimer and higher oligomers fraction-comprising compounds having a carbon number of 42 and higher.

16. A process for preparing a base stock, comprising:
(i) providing an olefinic feedstock comprising less than 8 wt % branched monomeric olefins and greater than 50 wt % monomeric alpha olefins, with the monomeric olefins having a carbon number in the range of from C14-C20;
(ii) conducting an oligomerization reaction with the olefinic feedstock of (i) at a temperature in the range of from 20 to 60° C., over a BuOH and BuAc co-catalyst, with a reaction residence time of from 60-180 minutes, in a semi-batch or continuous stirred tank reactor, while controlling the reaction conditions to obtain an intermediate with a dimers/fraction such that the dimers fraction of the intermediate when saturated without hydroisomerization results in a saturated dimer with a branching proximity of 27-35;
(iii) recovering the intermediate from the oligomerization reaction in step (ii), removing unreacted monomer by distillation, and recovering a bottoms distillation product;
(iv

Assignees

• Novvi Llc
• Chevron Usa Inc

Inventors

• Baralt Eduardo
• Chen Cong-Yan
• Hao Yalin
• Ho Liwenny
• Ho Willbe
• Pradhan Ajit
• Rosalli Jason
• Thomas Benton
• Wells Jason

Classifications

• B01J21/04

  Alumina · CPC title

• C07C7/04

  by distillation · CPC title

• C10G69/00

  Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one other conversion process (C10G67/00 takes precedence) · CPC title

• C10G2400/22

  Higher olefins · CPC title

• C10G45/00

  Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds · CPC title