Process for preparing an overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition
View Patent ↗Disclosed herein is an overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition, which is prepared by the process comprising (a) providing an overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition having a total base number (TBN) greater than about 250; and (b) sparging the overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition with air at a temperature ranging from about 190° C. to about 250° C.
1. A process for preparing an overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition comprising:
(a) providing an overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition having a total base number (TBN) greater than about 250; and
(b) sparging the overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition with air at a temperature ranging from about 190° C. to about 250° C.
2. The process of claim 1 , wherein the salt of a sulfurized alkyl-substituted hydroxyaromatic composition is produced by (i) alkylating a hydroxyaromatic compound with one or more normal alpha olefins; and (ii) sulfurizing, neutralizing and overbasing the alkyl-substituted hydroxyaromatic compound in any order.
3. The process of claim 2 , wherein the hydroxyaromatic compound is a phenol and the alkyl-substituted hydroxyaromatic compound is derived from alkylation of the hydroxyaromatic compound with C 9 to C 18 oligomers of monomers selected from propylene, butylene or mixtures thereof.
4. The process of claim 1 , wherein the overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition having a TBN greater than about 250 is an overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition having a TBN greater than about 250 and up to about 450.
5. The process of claim 1 , wherein the step of sparging is conducted under vacuum.
6. The process of claim 1 , wherein the step of sparging is conducted under pressure.
7. The process of claim 1 , wherein the resulting overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition is substantially free of an unsulfurized substituted hydroxyaromatic compound and its metal salt.
8. The process of claim 1 , wherein the resulting overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition contains less than about 1.5 wt. % of an unsulfurized alkyl-substituted hydroxyaromatic compound and its metal salt.
9. The process of claim 1 , wherein the resulting overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition contains less than about 0.3 wt. % of an unsulfurized alkyl-substituted hydroxyaromatic compound and its metal salt.