Method of manufacturing calcium sulfonate greases using delayed addition of non-aqueous converting agents

Patent metadata

Field	Value
Publication number	US-9976101-B2
Application number	US-201614990473-A
Country	US
Kind code	B2
Filing date	Jan 7, 2016
Priority date	Oct 31, 2011
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

A method of manufacturing an overbased calcium sulfonate grease comprising a reduced amount of overbased calcium sulfonate, water and at least one non-aqueous converting agent, where at least a portion of the non-aqueous converting agent is added after one or more delay periods relative to the addition of the water. A delay period may involve the period of time it takes to adjust the temperature of the mixture, a period of time during which the mixture is held at a temperature or within a range of temperatures, and multiples and any combination thereof. These calcium sulfonate greases have improved thickener yield and high dropping points compared to greases of substantially similar composition made without a delay between the additions of water and a non-aqueous converting agent, particularly when a poor quality overbased calcium sulfonate is used.

First claim

I claim:

1. A method for making a calcium sulfonate grease comprising the steps of:
mixing water, overbased calcium sulfonate containing dispersed amorphous calcium carbonate, and optionally base oil to form a first mixture;
adding at least a portion of one or more non-aqueous converting agents to the first mixture after one or more delay periods to form a pre-conversion mixture;
converting the pre-conversion mixture to a converted mixture by heating until conversion of the amorphous calcium carbonate contained in the overbased calcium sulfonate to crystalline calcium carbonate has occurred; and
wherein the grease is a complex calcium sulfonate grease comprising 30% or less overbased calcium sulfonate or the grease is a simple calcium sulfonate grease comprising around 30% to 70% overbased calcium sulfonate; and
wherein (a) at least one of the delay periods is a holding delay period wherein the first mixture or pre-conversion mixture is maintained at a temperature or within a range of temperatures for a period of time of at least 20 minutes or (b) at least one of the delay periods is a temperature adjustment delay period where the first mixture or pre-conversion mixture is heated to a temperature of at least 110 F or (c) the converting step comprises maintaining the pre-conversion mixture at temperature between about 190 F and 230 F or (d) a combination thereof.

2. The method according to claim 1 further comprising adding at least a portion of one or more of the non-aqueous converting agents to one or more of the following: the first mixture before any delay period, the first mixture during a delay period, or the pre-conversion mixture during one or more delay periods.

3. The method according to claim 2 wherein acetic acid is not added prior to the converting step.

4. The method according to claim 1 wherein the grease is a complex grease and further comprising the steps of:
mixing one or more complexing acids with the first mixture, pre-conversion mixture, converted mixture, or a combination thereof;
mixing at least one calcium containing base with the first mixture, pre-conversion mixture, converted mixture, or a combination thereof, wherein the calcium containing base comprises calcium hydroxyapatite, added calcium carbonate, or a mixture thereof; and
wherein the overbased calcium sulfonate comprises around 0% to 8% residual calcium oxide or calcium hydroxide.

5. The method according to claim 1 wherein at least one of the non-aqueous converting agents is a glycol, a glycol ether, or a glycol polyether.

6. The method according to claim 5 wherein the glycol is hexylene glycol.

7. The method according to claim 6 wherein a first portion of the hexylene glycol is added with the first mixture prior to any delay period and a second portion of the hexylene glycol is added to the first mixture or pre-conversion mixture after or during one or more delay periods; and
wherein the one or more delay periods between the addition of the first and second portions of hexylene glycol is (1) a holding delay period of at least 20 minutes; or (2) a temperature adjustment delay period where the first mixture or pre-conversion mixture is heated to a temperature of at least 160 F; or (3) both.

8. The method according to claim 1 wherein the mixing and converting are in an open vessel.

9. The method according to claim 1 wherein the converting is in a pressurized vessel.

10. The method according to claim 8 wherein the converting step comprises maintaining the pre-conversion mixture at temperature between about 190 F and 230 F.

11. The method according to claim 2 wherein at least a portion of one of the non-aqueous converting agents is added to the first mixture or the pre-conversion mixture during one of the delay periods by continuous addition at a substantially steady flow rate or by discrete additions in substantially even increments over the duration of the delay period.

12. The method according to claim 11 wherein at least a portion of the same or a different non-aqueous converting agent is batch added to the first mixture or pre-conversion mixture after one of the delay periods.

13. A method for making a calcium sulfonate grease comprising the steps of:
mixing water, overbased calcium sulfonate containing dispersed amorphous calcium carbonate, and optionally base oil to form a first mixture;
adding at least a portion of one or more non-aqueous converting agents to the first mixture after or during one or more delay periods to form a pre-conversion mixture;
converting the pre-conversion mixture to a converted mixture by heating until conversion of the amorphous calcium carbonate contained in the overbased calcium sulfonate to crystalline calcium carbonate has occurred;
wherein the grease is a complex calcium sulfonate grease comprising 45% or less overbased calcium sulfonate or the grease is a simple calcium sulfonate grease comprising around 30% to 70% overbased calcium sulfonate; and
wherein at least one of the delay periods is a holding delay period wherein the first mixture or pre-conversion mixture is maintained at a temperature or within a range of temperatures for a period of time of at least 20 minutes.

14. The method according to claim 13 wherein the overbased calcium sulfonate is a poor quality overbased calcium sulfonate.

15. The method according to claim 13 wherein the overbased calcium sulfonate is a good quality overbased calcium sulfonate.

16. The method according to claim 13 wherein the grease is a complex grease and further comprising the steps of:
mixing one or more complexing acids with the first mixture, pre-conversion mixture, converted mixture, or a combination thereof;
mixing at least one calcium containing base with the first mixture, pre-conversion mixture, converted mixture, or a combination thereof, wherein the calcium containing base comprises calcium hydroxyapatite, added calcium carbonate, or a mixture thereof; and
wherein the overbased calcium sulfonate comprises around 0% to 8% residual calcium oxide or calcium hydroxide.

17. The method according to claim 16 wherein no additional calcium oxide or calcium hydroxide is added as the calcium containing base for reacting with complexing acids.

18. The method according to claim 16 wherein the calcium containing base comprises calcium hydroxyapatite and one or more of the following: added calcium oxide, added calcium hydroxide, and added calcium carbonate.

19. The method according to claim 13 wherein the temperature or range of temperatures is between ambient temperature and around 190 F.

20. The method according to claim 13 wherein the period of time for the holding delay period is at least 30 minutes.

21. The method according to claim 13 wherein there are at least two delay periods.

22. The method according to claim 21 wherein one of the delay periods is a temperature adjustment delay period where the first mixture or pre-conversion mixture is heated or cooled.

23. The method according to claim 21 wherein at least a portion of one of the non-aqueous converting agents is added during or after a second or any subsequent delay period.

24. The method according to claim 21 wherein no non-aqueous converting agent is added during or immediately after a first of the delay periods.

25. The method according to claim 21 wherein at least a portion of one of the non-aqueous converting agents is batch added after one of the delay periods

Assignees

• Nch Corp

Inventors

• Waynick J Andrew

Classifications

• C10M2201/084

  containing sulfur, selenium or tellurium · CPC title

• C10M2203/1065

  used as base material · CPC title

• C10N2030/38

  Catalyst protection, e.g. in exhaust gas converters · CPC title

• C10M2215/064

  Di- and triaryl amines · CPC title

• C10M2223/043

  Ammonium or amine salts thereof · CPC title