Improvement in the preparation of overbased magnesium lubricant additives

Claim 2

IN A PROCESS FOR PREPARING A MAGNESIUM OVERBASED LUBRICANT ADDITIVE WHEREIN A REACTION MIXTURE OF AN OIL SOLUBLE DETERGENT OR DISPERANT SUSCEPTIBLE TO OVERBASING SELECTED FROM THE GROUP CONSISTING OF PHOSPHOSULPHURIZED HYDROCARBONS, METAL SALTS OF CARBOXYLIC ACIDS, SULPHONIC ACIDS AND METAL SALTS OF SULPHONIC ACID, A BASIC MAGNESIUM COMPOUND IN AN AMOUNT SUFFICIENT TO OVERBASE SAID OIL SOLUBLE DETERGENT OR DISPERANT, AND A REACTION PROMOTING AMOUNT OF A HYDROXYCONTAINING COMPOUND SELECTED FROM THE GROUP CONSISTING OF ALCOHOLS AND MONETHERS OF GLYCOLS IS FORMED IN AN INERT SOLVENT, SAID REACTION MIXTURE IS CONTACTED WITH AN ACIDIC GAS AT A REACTION TEMPERATURE OF FROM ABOUT 200 *C UP TO THE DECOMPOSITION TEMPERATURE OF THE REACTION MIXTURE AND THE RESULTANT PRODUCT IS HEATED TO REMOVE VOLATILE COMPONENTS; THE IMPROVEMENT COMPRISING: INCORPORATING IN SAID REACTION MIXTURE A REACTION PROMOTING AMOUNT UP TO ABOUT 40 PERCENT BY WEIGHT BASED ON THE OF THE INERT SOLVENT, OF A SALT OF AN ALKANOIC AICD CONTAINING FROM ONE TO 20 CARBON ATOMS AND AN ALIPHATIC HYDROCARBYL DIAMINE OR POLYAMINE CONTAINING FROM TWO TO EIGHT CARBON ATOMS.

Claim 3

The process of claim 1 wherein the oil soluble detergent or dispersant is present in the amount of about 10 to 150 percent by weight based on the weight of the inert solvent, the hydroxy containing organic compound is present in an amount of about 5 to 50 percent by weight, based on the weight of the inert solvent, the salt of the amine and acid is present in the reaction mixture in an amount of about 0.1 to 40 percent by weight, based on the weight of the inert solvent, about 5 to 50 percent by weight, based on the weight of the inert solvent, of water is present in the reaction mixture and wherein the acidic gas is carbon dioxide.

Claim 4

The process of claim 2 wherein the said salt is a neutral salt of formic acid and an aliphatic hydrocarbyl diamine containing from two to eight carbon atoms.

Claim 5

The process of claim 3 wherein the salt is ethylene diamine diformate.

Claim 6

The process of claim 2 wherein the basic magnesium compound is magnesium oxide or magnesium hydroxide.

Claim 7

The process of claim 2 wherein the inert solvent is a hydrocarbon.

Claim 8

The process of claim 2 wherein the hydroxy containing organic compound is selected from the group consisting of monohydroxis alcohols, containing from one to four carbon atoms, glycols containing from one to four carbon atoms and monoethers of glycols containing from one to four carbon atoms.

Claim 9

The process of claim 2 wherein the reaction mixture is formed by admixing the inert solvent, the oil-soluble detergent or dispersant, the basic magnesium compound and the hydroxy containing organic compound and thereafter adding thereto an aqueous solution of the amine salt of the acid.

Claim 10

The process of claim 2 wherein the basic magnesium compound is present in an amount to provide an additive having a total base number of from about 250 to 500 mg. KOH/g.

Claim 11

The process of claim 2 wherein the inert solvent is selected from the group consisting of mineral oils, alkylated benzene and mixtures thereof.

Claim 12

ThE process of claim 2 wherein the inert solvent is a synthetic ester lubricating oil.

Claim 13

The process of claim 2 wherein the hydroxy containing organic compound is methanol.

Claim 14

The process of claim 2 wherein a non-polar diluent is also included in the reaction mixture.

Claim 15

The process of claim 2 wherein the non-plar diluent is selected from the group consisting of xylene, benzene, toluene and petroleum ether.

Claim 16

The process of claim 2 wherein from about 10 to 25 percent by weight, based on the weight of the inert solvent, of water is added to the reaction mixture during treatment of said reaction mixture with carbon dioxide.

Claim 17

The process of claim 1 wherein the inert solvent is a hydrocarbon oil solvent, the oil soluble detergent or dispersant is an oil soluble neutral magnesium salt of sulphonic acid in an amount of about 20 to 120 percent by weight, based on the weight of the hydrocarbon oil solvent; the basic magnesium compound is magnesium oxide or magnesium hydroxide in an amount to provide an additive having a total base number of about 250 to 500 mg. KOH/g.; the hydroxy-containing compound is methanol in an amount of about 25 to 50 percent by weight, based on the weight of the hydrocarbon oil solvent; the salt of an alkanoic acid and an aliphatic hydrocarbyl diamine is present in an amount of about 0.1 to 15 percent by weight, based on the weight of the hydrocarbon oil solvent; from about 5 to 50 percent by weight, based on the weight of the hydrocarbon oil solvent, of water is present in the reaction mixutre; and the reaction mixture is treated with carbon dioxide at a temperature of from about 20*C up to the reflux temperature of the reaction mixture until the magnesium oxide or magnesium hydroxide is substantially converted to magnesium carbonate.

Claim 18

An oil-soluble additive prepared according to the process of claim 1.

Claim 19

An oil-soluble additive prepared according to the process of claim 3.

Claim 20

An oil-soluble additive prepared according to the process of claim 16.

Claim 21

A lubricant comprising a major amount of lubricating oil containing from 0.1 to 10 percent by weight, based on the total weight of the lubricant, of an oil-soluble additive according to claim 17.

Claim 22

A lubricant comprising a major amount of lubricating oil containing from 0.1 to 10 percent by weight, based on the total weight of the lubricant, of an oil-soluble additive according to claim 18.

Claim 23

A lubricant comprising a major amount of lubricating oil containing from 0.1 to 10 percent by weight, based on the total weight of the lubricant, of an oil-soluble additive according to claim 19.

Claim 24

The process of claim 1 wherein the amine salt of the acid is a neutral salt.