Fuel And Oil Detergents

Abstract

This invention is directed to lubricating compositions which contain detergent-dispersant components derived from substantially linear alkylbenzenes including sulfonates, overbased sulfonates, and salts and esters thereof. Detergents provided by the invention have a low content of the 1-aryl isomers than materials of prior art. In addition, the detergents of the present invention are prepared using alkylbenzene mixtures which have substantially-reduced benzene content over materials provided by the prior art. The invention provides compositions which are useful in formulating lubricants, motor oils, and the like.

1 ) A mixture of alkylbenzenes from which an overbased alkaline earth sulfonate may be prepared, which mixture comprises two or more 2-aryl isomers of alkylbenzenes having the structure:  
       
         
           
           
               
               
           
         
       
       in which: 
 n is any integer between 12 and 30;  
 R 1 , R 2 , R 3 , R 4 , and R 5  are each independently selected from the group consisting of: hydrogen, a methyl group, an ethyl group, a propyl group, and a butyl group;  
 B is selected from the group consisting of: hydrogen, methyl, or ethyl;  
 B is attached to any single carbon atom along the —(CH 2 ) n — portion of the alkyl chain; and  
 the total 2-aryl isomer content of said mixture of alkylbenzenes is between about 8% and about 30% by weight based on the total weight of all alkylbenzenes present in said mixture.  
 
     
     
         2 ) A mixture according to  claim 1  which contains less than about 2 parts per million of benzene by weight based on the total weight of said mixture.  
     
     
         3 ) A mixture according to  claim 1  which contains less than about 1 parts per million of benzene by weight based on the total weight of said mixture.  
     
     
         4 ) A mixture according to  claim 1  which contains less than about 0.5 parts per million of benzene by weight based on the total weight of said mixture.  
     
     
         5 ) A mixture according to  claim 1  which contains less than about 100 parts per billion of benzene by weight based on the total weight of said mixture.  
     
     
         6 ) A mixture according to  claim 1  in which B is hydrogen for between about 72% and about 98% of all alkylbenzenes present, by weight, based on the total weight of said mixture.  
     
     
         7 ) A mixture according to  claim 1  in which the amount of 1-aryl isomers present is less than about 0.3% by weight based on the total weight of said mixture.  
     
     
         8 ) A mixture according to  claim 1  in which the amount of 1-aryl isomers present is any amount in the range of between about 0.01% to about 0.3% by weight based on the total weight of said mixture.  
     
     
         9 ) An overbased sulfonate made by sulfonating a mixture according to  claim 1 , and subsequently overbasing with an alkaline earth metal and carbon dioxide, or an alkali metal and carbon dioxide, until the base number of said overbased sulfonate is at least 250.  
     
     
         10 ) A process for producing an overbased sulfonate which comprises the steps of: 
 a) providing a mixture of aromatic alkylates which comprises two or more 2-aryl isomers having the structure:                          in which:    n may be equal to any integer between 12 and 30;    R 1 , R 2 , R 3 , R 4 , and R 5  are each independently selected from the group consisting of: hydrogen, a methyl group, an ethyl group, a propyl group, and a butyl group;    B is selected from the group consisting of: hydrogen, methyl, or ethyl;    B is attached to any single carbon atom along the —(CH 2 ) n — portion of the alkyl chain; and    the 2-aryl content of said mixture of aromatic alkylates is between about 8% and about 30% by weight based on the total weight of said mixture;    said mixture contains an amount of 1-aryl isomer that is less than about 3% by weight based on the total weight of all aromatic alkylates present in said mixture; and 
 b) reacting said mixture of aromatic alkylates with a source of sulfur trioxide, thus yielding an alkylaryl sulfonic acid;  
 c) combining said alkylaryl sulfonic acid with: 
 i) a source of an alkaline earth metal selected from calcium, strontium, and magnesium;  
 ii) water;  
 iii) a lower alcohol;  
 iv) optionally, a hydrocarbon solvent; and  
 v) carbon dioxide,  
 under conditions favorable to formation of an overbased sulfonate, wherein the final overbased sulfonate has a total base number of any value in the range of about 200 to about 375.  
 
   
     
     
         11 ) A process according to  claim 10  further comprising the step of: d) filtering said overbased sulfonate to remove solids.  
     
     
         12 ) A process according to  claim 11  further comprising the step of: e) diluting said overbased solvent with a material selected from the group consisting of: a hydrocarbon solvent and a base oil.  
     
     
         13 ) A process according to  claim 10  in which said mixture of aromatic alkylates contains less than about 2 ppm benzene.  
     
     
         14 ) A process according to  claim 10  in which said mixture of aromatic alkylates contains less than about 1 ppm benzene.  
     
     
         15 ) A process according to  claim 10  in which said mixture of aromatic alkylates contains less than about 0.5 ppm benzene.  
     
     
         16 ) A process according to  claim 10  in which said mixture of aromatic alkylates contains less than about 0.3% by weight of 1-aryl isomers of alkylbenzenes.  
     
     
         17 ) A composition useful as a lubricant, which composition is formed by mixing a base oil with an effective detergent-dispersant amount of an alkylbenzene-derived detergent component that is made by sulfonating, and optionally overbasing, a mixture of alkylbenzenes, which mixture comprises two or more 2-aryl isomers of alkylbenzenes having the structure:  
       
         
           
           
               
               
           
         
       
       in which: 
 n is any integer between 12 and 30;  
 R 1 , R 2 , R 3 , R 4 , and R 5  are each independently selected from the group consisting of: hydrogen, a methyl group, an ethyl group, a propyl group, and a butyl group;  
 B is selected from the group consisting of: hydrogen, methyl, or ethyl;  
 B is attached to any single carbon atom along the —(CH 2 ) n — portion of the alkyl chain; and  
 the total 2-aryl isomer content of said mixture of alkylbenzenes is between about 8% and about 30% by weight based on the total weight of all alkylbenzenes present in said mixture.  
 
     
     
         18 ) A composition according to  claim 17  wherein said mixture of alkylbenzenes contain any amount between about 10% and about 20% of said 2-aryl isomers, by weight, based on the total weight of all alkylbenzenes present in said mixture.  
     
     
         19 ) A composition according to  claim 17  in which said mixture of alkylbenzenes contain less than about 2 ppm of benzene by weight.  
     
     
         20 ) A composition according to  claim 17  in which said mixture of alkylbenzenes contain less than about 1 ppm of benzene by weight.  
     
     
         21 ) A composition according to  claim 17  in which said mixture of alkylbenzenes contain less than about 0.5 ppm of benzene by weight.  
     
     
         22 ) A composition according to  claim 17  wherein said alkylbenzene-derived detergent component is present in any amount between 0.03% and 49.95% by weight based upon the total weight of said composition useful as a lubricant.  
     
     
         23 ) A composition as in  claim 17  wherein the alkylbenzene-derived detergent component is predominantly comprised of molecules which comprise only one alkyl group bonded to a benzene ring, and wherein none of R 1 , R 2 , R 3 , R 4 , or R 5  are hydrocarbyl.  
     
     
         24 ) A composition as in  claim 23  wherein the alkyl group is substantially linear.  
     
     
         25 ) A composition as in  claim 23  wherein the alkyl group is a branched alkyl group.  
     
     
         26 ) A composition according to  claim 17  wherein said alkylbenzene-derived detergent component is present in any amount between 0.10% and 25.00% by weight based upon the total weight of said composition useful as a lubricant.  
     
     
         27 ) A composition according to  claim 17  in which said mixture of alkylbenzenes contains less than about 0.3% by weight 1-aryl isomers of alkylbenzenes.  
     
     
         28 ) A composition according to  claim 17  in which the 1-aryl alkylbenzenes isomers content of said mixture of alkylbenzenes is any value in the range of between about 0.01% and about 0.3% by weight based on the total weight of said mixture.  
     
     
         29 ) A composition useful as a lubricant that is formed from components comprising: 
 a) an alkylbenzene-derived component present in any amount between about 0.01% and about 50% by weight based upon the total weight of the composition, which alkylbenzene-derived component is selected from the group consisting of: sulfonates and overbased sulfonates of an alkylbenzenes mixture in which the content of 2-aryl isomers in said alkylbenzenes mixture is any value between about 10% and about 30% by weight based on the total weight of the alkylbenzenes mixture, wherein said 2-aryl isomers are described by the general formula:                          in which n is equal to any integer between about 14 and about 27, and in which one and only one of R 1 , R 2 , R 3 , R 4 , and R 5  is a sulfur-containing appendage selected from the group consisting of: a sulfonic acid group, a sulfonate group, and a sulfonate ester group; and    wherein the groups R 1 , R 2 , R 3 , R 4 , and R 5  which are not a sulfur-containing group are each independently selected from the group consisting of: hydrogen, a methyl group, an ethyl group, a propyl group, and a butyl group; and    b) at least 50% by weight of a base oil,    wherein said alkylbenzene-derived component contains one or more metals selected from the group consisting of: lithium, sodium, potassium, strontium, magnesium, and calcium.    
     
     
         30 ) A composition according to  claim 29  in which said alkylbenzene-derived component is a mixture of sulfonate salts of metals selected from the group consisting of: alkali metals or alkaline earth metals.  
     
     
         31 ) A composition according to  claim 29  in which said alkylbenzene-derived component is an overbased sulfonate which comprises a mixture of isomers of alkaline earth metal alkylbenzene sulfonates, which mixture includes one or more metals selected from the group consisting of: Sr, Mg, Ba, and Ca.  
     
     
         32 ) A composition according to  claim 29  in which said alkylbenzene mixture contains less than about 2 parts per million of benzene by weight based on the total weight of said alkylbenzene mixture.  
     
     
         33 ) A composition according to  claim 29  in which said alkylbenzene mixture contains less than about 1 parts per million of benzene by weight based on the total weight of said alkylbenzene mixture.  
     
     
         34 ) A composition according to  claim 29  in which said alkylbenzene mixture contains less than about 0.5 parts per million of benzene by weight based on the total weight of said alkylbenzene mixture.  
     
     
         35 ) A composition according to  claim 29  in which said alkylbenzene mixture contains less than about 100 parts per billion of benzene by weight based on the total weight of said alkylbenzenes mixture.  
     
     
         36 ) A composition according to  claim 29  in which B is hydrogen for between about 72% and about 98% of all alkylbenzenes present in said alkylbenzene mixture, by weight, based on the total weight of said alkylbenzenes mixture.  
     
     
         37 ) A composition according to  claim 29  in which the amount of 1-aryl isomers present in said alkylbenzene mixture is less than about 0.3% by weight based on the total weight of said alkylbenzenes mixture.  
     
     
         38 ) A composition according to  claim 29  in which the amount of 1-aryl isomers present in said alkylbenzene mixture is any amount in the range of between about 0.01% to about 0.3% by weight based on the total weight of said alkylbenzenes mixture.  
     
     
         39 ) A composition of matter comprising: 
 a) a major amount of a material selected from the group consisting of: a motor fuel, a hydrocarbon diluent, or a base oil; and    b) a minor amount of a mixture of alkaline earth metal salts of overbased alkylbenzene sulfonates, which mixture comprises two or more 2-aryl isomers of overbased alkylbenzene sulfonates which are derived from a mixture of alkylbenzene sulfonates comprising at least two 2-aryl isomers of the structure:                          in which:    n is any integer between about 12 and about 30;    R 1 , R 2 , R 3 , R 4 , and R 5  are each independently selected from the group consisting of: hydrogen, a methyl group, an ethyl group, a propyl group, a butyl group, a sulfonic acid group, and a sulfonate group;    B is selected from the group consisting of: hydrogen, methyl, or ethyl;    B is attached to any single carbon atom along the —(CH 2 ) n — portion of the alkyl chain; and    the total 2-aryl isomer content of said mixture of overbased alkaline earth sulfonates is between about 8% and about 30% by weight based on the total weight of all overbased alkylbenzene sulfonates present in said mixture, and in which the 1-aryl isomer content is less than about 3% by weight based on the weight of all isomers of overbased alkylbenzene sulfonates present, subject to the proviso that the sulfate or sulfonic acid group which is overbased is located at least one of R 1 , R 3 , and R 5 .    
     
     
         40 ) A composition according to  claim 39  in which B is hydrogen for between about 72% and about 98% of all overbased alkylbenzene sulfonates present, on a molar basis.  
     
     
         41 ) A composition according to  claim 39  in which the amount of 1-aryl isomers present is less than about 0.3% by weight based on the total weight of all overbased sulfonates present.  
     
     
         42 ) A composition according to  claim 39  in which the amount of 1-aryl isomers present is any amount in the range of between about 0.01% to about 0.3% by weight based on the total weight of all overbased sulfonates present.  
     
     
         43 ) A concentrate which comprises: 
 a) an alkylbenzene-derived detergent component, said component characterized as comprising any amount between about 10% and about 30% by weight based upon the total weight of the component, of derivatives of at least two different 2-aryl isomers of alkylbenzenes described by the general formula:                          wherein n is equal to any integer between 14 and 28, and in which R 1 , R 2 , R 3 , R 4 , and R 5  are each independently selected from the group consisting of: hydrogen, a methyl group, an ethyl group, a propyl group, a butyl group, a sulfonic acid group, a sulfonate group, and a sulfonate ester group; and    b) a base oil.    
     
     
         44 ) A concentrate according to  claim 43  in which the content of detergents which are derived from 1-aryl alkylbenzene isomers is less than about 0.3% by weight based on the total weight of all alkylbenzene-derived detergents present.  
     
     
         45 ) A concentrate according to  claim 43  in which the content of detergents which are derived from 1-aryl alkylbenzene isomers is any amount between about 0.01% and about 0.03% by weight based on the total weight of all alkylbenzene-derived detergents present.  
     
     
         46 ) A composition of matter according to  claim 43  wherein the viscosity of the alkylbenzene mixture is less than 140 SUS units at 37.8 degrees centigrade.  
     
     
         47 ) A mixture according to  claim 43  wherein the viscosity of the mixture is less than 120 SUS units at 37.8 degrees centigrade.  
     
     
         48 ) A mixture according to  claim 43  wherein the viscosity of the alkylbenzene mixture is less than 100 SUS units at 37.8 degrees centigrade.  
     
     
         49 ) The process of providing a metal surface with a lubricating film comprising the step of contacting a composition according to  claim 43  to said metal surface.