Particulate reduction in gdi engines using mannich detergents

Abstract

The present disclosure relates to fuel additive packages, fuels, and methods of achieving emission particulate reductions in gasoline direct injection (GDI) engines using select Mannich detergents (e.g., reaction products of a hydrocarbyl-substituted hydroxyaromatic compound, an aldehyde, and an amine). In one approach or embodiment, the select Mannich detergents herein for emissions particulate reductions include one or more of the following characteristics: (i) certain molar ratios of the hydroxyaromatic compound, the amine, and the aldehyde; (ii) select oligomer structures; and/or (iii) certain isomeric forms of polyisobutylene substituents on the hydroxyaromatic compound.

What is claimed is: 
     
         1 . A method of reducing particulate emission in a gasoline direct injection engine, the method comprising:
 combusting in the engine a gasoline composition including a Mannich detergent as an additive, wherein the Mannich detergent is produced by the reaction of hydrocarbyl-substituted phenol, an amine, and formaldehyde at a molar ratio of 1:1-2:2-3; and   wherein the Mannich detergent is present in the gasoline composition at a concentration of about 40 to about 100 ppm.   
     
     
         2 . The method of  claim 1 , wherein the molar ratio of the hydrocarbyl-substituted phenol, amine, and formaldehyde is 1:1-2:2. 
     
     
         3 . The method of  claim 1 , wherein the molar ratio of the hydrocarbyl-substituted phenol, amine, and formaldehyde is 1:2:2. 
     
     
         4 . The method of  claim 1 , wherein the hydrocarbyl substituent is derived from polyisobutylene and wherein at least 50 mol percent of polyisobutylene macromolecules have a tri-substituted alkene group, or wherein the hydrocarbyl substituent is derived from polyisobutylene and wherein at least 50 mol percent of polyisobutylene macromolecules have a tri-substituted alkene group and a tetra-substituted alkene group. 
     
     
         5 . The method of  claim 4 , wherein the polyisobutylene having a tri-substituted alkene group has the following stereochemistry: 
       
         
           
           
               
               
           
         
         wherein
 R 1  is a polymer chain 
 R 2  is —H or —CH 3 . 
 
       
     
     
         6 . The method of  claim 4 , wherein the polyisobutylene has less than 50 mol percent of terminal double bonds. 
     
     
         7 . The method of  claim 4 , wherein the polyisobutylene includes one or more of a β-olefin isomer structure, a β-olefin structure, or a tetra-substituted olefin structure. 
     
     
         8 . The method of  claim 1 , wherein the Mannich detergent is an oligomer. 
     
     
         9 . The method of  claim 1 , wherein the hydrocarbyl substituent is derived from polyisobutylene having a number average molecular weight of about 400 to about 1500. 
     
     
         10 . The method of  claim 9 , wherein at least 50 mol percent of polyisobutylene macromolecules have a tri-substituted alkene group, or wherein at least 50 mol percent of polyisobutylene macromolecules have a tri-substituted alkene group and a tetra-substituted alkene group. 
     
     
         11 . The method of  claim 1 , wherein the Mannich detergent is a compound having a structure of Formula I: 
       
         
           
           
               
               
           
         
         wherein
 each R 2  is independently H or, together with the R 4  or R 5  moiety in an adjacent —CH(R 3 )NR 4 R 5  group, is a divalent —CH(R 3 )— group; 
 x is an integer of 1, 2 or 3; 
 each R 3  is independently H or hydrocarbyl comprising 1 to 10 carbon atoms; 
 each R 4  and R 5  is independently H, hydrocarbyl comprising 1 to 3000 carbon atoms which may be interrupted by one or more O, S and/or NR 3  moieties, or together with R 2  forms a divalent —CH(R 3 )— group as defined above; 
 y is an integer of 1, 2 or 3; 
 each R 6  is independently hydrocarbyl comprising 1 to 3000 carbon atoms which may be interrupted by one or more O, S and/or NR 3  moieties; 
 z is an integer of 0, 1 or 2; 
 n is an integer of 1, 2 or 3; and 
 Q is the hydrocarbyl substituent. 
 
       
     
     
         12 . The method of  claim 11 , wherein, in at least 50% of the compounds of formula (I), said Q group is bonded to the central benzene ring such that it has the structure: 
       
         
           
           
               
               
           
         
         wherein
 R 1  is a polymer chain, and together with the moiety —CH 2 —C(CH 3 )(CH 2 CH 3 )— through which it is attached to the central benzene ring, represents the Q group; and 
 R 7  is —H or —CH 3 . 
 
       
     
     
         13 . The method of  claim 11 , wherein (1) any Q groups are para to an —OR 2  group, (2) any —CH(R 3 )NR 4 R 5  groups are ortho to at least one —OR 2  group, and/or (3) —R 6  (if present) is ortho to at least one —OR 2  group. 
     
     
         14 . The method of  claim 11 , wherein the hydrocarbyl substituent Q is derived from polyisobutylene and wherein at least 50 mol percent of polyisobutylene macromolecules have a tri-substituted alkene group, or wherein the hydrocarbyl substituent Q is derived from polyisobutylene and wherein at least 50 mol percent of polyisobutylene macromolecules have a tri-substituted alkene group and a tetra-substituted alkene group. 
     
     
         15 . The method of  claim 11 , wherein the Mannich detergent is a compound having a structure of Formula (Ia), (Ib), and/or (Ic): 
       
         
           
           
               
               
           
         
       
     
     
         16 . The method of  claim 15 , wherein the —NR 4 R 5  group of Formula (Ia), (Ib), and/or (Ic) is —NH(CH 2 ) 3 N(CH 3 ) 2 . 
     
     
         17 . The method of  claim 15 , wherein the hydrocarbyl substituent Q is derived from polyisobutylene and wherein at least 50 mol percent of polyisobutylene macromolecules have a tri-substituted alkene group, or wherein the hydrocarbyl substituent is derived from polyisobutylene and wherein at least 50 mol percent of polyisobutylene macromolecules have a tri-substituted alkene group and a tetra-substituted alkene group. 
     
     
         18 . The method of  claim 1 , wherein the amine is an alkylene polyamine. 
     
     
         19 . The method of  claim 18 , wherein the alkylene polyamine is ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, or mixtures of alkylene polyamines of the formula H 2 N— (A-NH—) n H where A is divalent ethylene or propylene and n is an integer of from 1 to 10.