Patent GB-1068547-A (GB)
Title: Metal carbonate overbased lubricant detergent-dispersants
IPC: C10M159/20
Filed: 1964-11-13
Abstract: An overbased detergent-dispersant suitable for oil compositions is obtained by the action of carbon dioxide on alkali metal oxides, alkali metal hydroxides, alkaline earth metal oxides or alkaline earth metal hydroxides in the presence of a dispersant, which is one of: the reaction product of an alkenyl succinic anhydride with a polyamine, the reaction product of an alkenyl succinic anhydride with a polyamine and a carboxylic acid, the reaction product of an alkenyl succinic anhydride with a polyhydric alcohol or an alkanolamine and subsequently with a polyamine or the product obtained by further reacting the reaction product of an alkenyl succinic anhydride and a polyamine and a carboxylic acid with a phosphosulphurized hydrocarbon or a dialkyl dithiophosphoric acid.  The compositions may contain 10-35% by weight of metal carbonate and 5-50% of dispersant as above. In lubricating oil (mineral or synthetic) compositions from 0.001-10% of detergent-dispersant may be employed.  Fuel compositions may be a major proportion of middle distillate fuel and 0.002 to 2% of the detergent dispersant.  Other conventional ingredients are specified.ALSO:Compositions comprising colloidal alkali metal or alkaline earth metal carbonates are prepared by the action of carbon dioxide on alkali metal oxides, alkali metal hydroxides, alkaline earth metal oxides or alkaline earth metal hydroxides in the presence of a dispersant which is one of, the reaction product of an alkenyl succinic anhydride with a polyamine, the reaction product of an alkenyl succinic anhydride with a polyamine and a carboxylic acid, the reaction product of an alkenyl succinic anhydride with a polyhydric alcohol or an alkanolamine and subsequently with a polyamine, or the product obtained by further reacting the reaction product of an alkenyl succinic anhydride and a polyamine and a carboxylic acid with a phosphosulphurized hydrocarbon or a dialkyl dithiophosphoric acid.  The alkenyl succinic anhydrides may contain alkenyl groups containing a total of 40-250 carbon atoms, such as polymers of C2 to C5 monoolefins with molecular weights of from 500-3,500, e.g. polymers of propylene or isobutylene of molecular weight 700-1,700.  The aliphatic polyamine may be diethylene triamine, tetraethylene pentamine, octaethylene nonamine and tetrapropylene pentamine and may be of general formula <FORM:1068547/C1/1> where n is 2 or 3 and m is from 0 to 10.  N-amino alkyl piperazines and mixtures of each of the above may be used.  The carboxylic acid may be acetic, fumaric, adipic, lauric, oleic, linoleic or stearic acids.  The polyhydric alcohols may be ethylene glycol, butanediol-1-4, pentanediol-1-5, octylene glycol and polyalkylene glycols such as polyethylene glycols and polypropylene glycols.  The alkanolamines include triethanolamine and diethanolamine. The phosphosulphurized hydrocarbon may be polyisobutylene.  The preparation is carried out in a mixture of dispersant and oil in the presence of a polar material, e.g. water. Auxiliary surface-active agents may be present in the preparation, such as, amyl phenol, octyl phenol, nonyl phenol, benzoic acid, oleic acid, tall oil fatty acids, isopropanolamine, ethylene diamine and diethylene triamine.  Two methods are described.  First, a high-speed mixing blend of the anhydride derivative and any auxiliary agent, 1-15 weight per cent, is prepared in hydrocarbon oil, e.g. light lubricating oil, 20-80 weight per cent, at 30-200 DEG F. and high-speed stirring is applied, the metal compound 10-50 weight per cent is added gradually and CO2 is passed at 400-500 DEG  F.  The mixture is dehydrated at 200-400 DEG  F. and filtered at 100-400 DEG F.  In a second method, a C1 to C3 aliphatic alcohol is dispersed in a liquid hydrocarbon at ambient temperature (droplets of smaller than 400 <\>pA), heated to 100-250 DEG  F., the oxide or hydroxide is added, CO2 is passed at 125-300 DEG  F. and water is removed by sparging with an inert gas such as nitrogen at 200-400 DEG  F. Passage of CO2 takes 1.5 to 2.5 hours until exit gas shows unreacted CO2 exceeds 90%.  The oxides and hydroxides may be those of sodium, potassium, lithium, barium, strontium, calcium and magnesium and mixtures thereof.