CA1287830C - Superalkalinized hydrolysis-resistant detergent or dispersant additives for lubricating oils, and process for their preparation - Google Patents

Abstract

. The invention relates to over-alkalized detergent-dis-persistent additives for lubricating oils, characterized in that they are obtained by neutralization of an alkylphenol using an alkaline earth base in the presence of a "carrier" alcohol. and of a third solvent forming an azeotrope with the reaction water, said neutralization operation being carried out at a temperature at least equal to that of formation of the azeotrope, (alkaline earth base / alkylphenol = 0.5 to 2 and "vector" alcohol / alkylphenol = 0.05 to 3); distillation under nitrogen sweep of the reaction medium obtained until complete elimination of the "vector" alcohol and the azeotrope; carboxylation of the alkylphenate formed into alkylsalicylate using carbon dioxide at a temperature of 100 to 185.degree.C under a pressure of at least 5 bar for at least 3 hours in the presence of a dilution oil or d 'an aromatic solvent, the amount of CO2 corresponding to that necessary to obtain a conversion rate expressed in acids of the alkylphenate to alkylsalicylate of between approximately 5 and 30%; or else sulfurization-over-alkalization of the alkylphenate-alkylsalicylate mixture obtained with elemental sulfur in the presence of an alkaline earth base, an alkylene glycol and a third solvent at a temperature of the order of 140 to 230.degree. C, (sulfur / starting alkylphenol = 0.7 to 1.5, total alkaline earth base / starting alkylphenol? 1.7 and alkaline earth base of overbasing / alkylene glycol = 1 to 1.6); or a sulfurization of the alkylphenatealkylsalicylate mixture obtained with elemental sulfur in the presence of an alkali hydroxide as catalyst at a temperature between 140 and 230.degree.C, and a third solvent forming an azeotrope with the reaction water sulfur / starting alkylphenol = 0.7 to 1.5, alkali hydroxide / starting alkylphenol 0.01 to 0.03) and over-alkalinization of the sulfurized alkylphenate-sulfurized alkylsalicylate mixture by addition of an alkaline earth base at a temperature from 50 to 80.degree.C in the presence of an alkylene glycol and a third solvent forming an azeotrope with the reaction water (total alkaline earth base / starting alkylphenol of? 1.7 and alkaline earth base of over-alkalinization / alkylene glycol = from 1 to 1.6); then carbonation of the medium obtained by carbon dioxide at a temperature of 100-185.degree.C and under a pressure close to atmospheric pressure, the amount of CO2 used being between that which can be completely absorbed by the reaction medium and an excess 30 of that amount; optional hydrolysis, then elimination by distillation of the alkylene glycol and of the third solvent after addition of dilution oil; and filtration to remove sediment.

Description

~ Z ~ 330 The present invention has for ob ~ and new additives overbased detergent-dispersants hydrolytically stable for lubricating oils and their preparation process.
It is well known (U.S. Patent No. 3,036,971) to prepare detergent-dispersant additives based on alkylphenates sulphurized with alkaline earth metals of high basicity by sulfurization of an alkylphenol, neutralization of the alkylphenol sulfurized using an alkaline earth base, then over-alkalinization by carbonation of the sulfurized alkylphenate;
this type of product has the disadvantage of being unstable at hydrolysis, which entered ~ no risk of clogging of filters marine engines, especially when this type of product is strongly overbased.
It is also known (French Patent No. 1,563,557) from prepare detergent additives based on alkylsalicylates sulphurized with calcium by carboxylation of an alkylphenate potassium, exchange with calcium chloride, then sulfurization calcium alkylsalicylate obtained by sulfur in the presence of lime, a carboxylic acid and an alkylene glycol or alkylene glycol alkyl ether. Such a method presents the disadvantage of requiring an exchange reaction.
The object of the present invention is to improve the stability at hydrolysis of additives based on sulfurized alkylphenates lineages, derivatives of alkylphenols carrying one or more killing alkyls in C8-C30, preferably in C12-C30, in order to prevent prevent clogging of filters and prevent loss of TBN
(Total Basic Number - Standard ASTM D 2896) in the presence of acid sulfuric.
The new additives which are the subject of the invention are characterized in that they are obtained by:
1) neutralization of an alkylphenol carrying one or more C8-C30 alkyl substituents, preferably C12-C30 using of an alkaline earth base in the presence of a "vector" alcohol 9 chosen from C1-C3 monoalcohols, alkylene glycols or ~ 1 2 ~ 3 ~ 7 ~ 330 alkoxy alkanols of formula R (OR '~ OH where R is is an alkyl radical in Cl-C4, R 'is an alkyl radical in C2-C3 and x is equal to I or 2 and a third solvent forming an azeotrope with the reaction water chosen from aromatic or aliphatic point hydrocarbons boiling above 7CC and boiling point alcohols higher than 120 C and preferably higher than 150 C, said neutralization operation being carried out at a temperature at less equal to that of formation of the azeotrope, the amounts of reagents used corresponding to the molar ratios following:
. alkaline earth / alkylphenol base ranging from 0.5 to 2 and preferably 0.6 to 1.6 . "carrier" alcohol / alkylphenol ranging from 0.05 to 3 and preferably from 0.1 to 1.5;

2) distillation under nitrogen sweep of the reaction medium obtained until complete elimination of the "vector" alcohol and the azeotrope;

3) carboxylation of the alkylphenate formed into alkylsalicylate to using carbon dioxide at a temperature of 100 to 185C (from preferably 140- lg5C) under a pressure of at least 5 bar (of preferably up to bar) for at least 3 hours in the presence ~ 'a dilution oil or an aromatic solvent, the amount of C2 corresponding to that necessary to obtain a rate of transformation expressed in acids of the alkylphenate into alkylsalicylate between about 5 and 30 ~;

4) sulfurization-over-alkalization of the alkylphenate mixture-alkylsalicylate obtained by elemental sulfur in the presence of a alkaline earth base, alkylene glycol and a third solvent chosen from aromatic hydrocarbons, hydrocarbons aliphatics and alcohols with a boiling point above 120 C and preferably above 150 C, at a temperature of around 140 to 230 C, the quantities of reagents used corresponding to the following molar ratios:
. starting sulfur / alkylphenol ranging from 0.7 to 1.5, from preferably 0.7 to 1.3 . total alkaline earth base / starting alkylphenol 1.7 at least and preferably ranging from 1.7 to 2 - ~ 1 2 ~ 37 ~ 330 . alkaline earth base of overbasing / alkylene glycol ranging from 1 to 1.6 then carbonation of the medium obtained by carbon dioxide at a temperature of 100 ~ 185 C and under a pressure close to the atmospheric pressure, the quantity of C02 used being included between that which can be completely absorbed by the medium reaction and an excess of 30% of this amount;
S) possible hydrolysis, then elimination by distillation of alkylene glycol and third solvent after addition of dilution; and 6) filtration to remove sediment.
Among the alkaline earth bases which can be used work to carry out the various stages of preparation of additives forming the subject of the invention, there may be mentioned oxides or hydroxides of calcium, barium or strontium and tou ~ particu-especially those of calcium.
Among the "vector" alcohols that can be used, mention may be made of methanol, propanol, ethylene glycol, diethylene glycol, methoxy-ethanol, 2-butoxyethanol, 2-butoxypropanol, propylene glycol methyl ether; the methanol and glycol are the preferred "carrier" alcohols.
Among the third solvents that can be used, one can cite xylene, toluene, cyclohexane, ethyl-2-hexanol, oxo alcohols, decyl alcohol, tridecyl alcohol, butoxy-2 ethanol, 2-butoxypropanol, propylene methyl ether-glycol; alcohol couples are particularly preferred "vector" / following third solvent: glycol / 2-ethylhexanol, glycol / cyclohexane, glycol / xylene, methanol / xylene.
The 1st stage, that is to say that of neutralization of the alkylphenol, is favorably carried out at a pressure close to atmospheric pressure, at a temperature at least equal to that of formation of the water-third solvent a ~ eotrope; when the third-solvent chosen is 2-ethyl hexanol a temperature of the order of 160-170 C is preferred; when this is cyclohexane ~ a temperature of 70-80 C is well suited; in a general way, the neutralization step is carried out at a temperature of the order from 50 to 2 ~ 0D C; the operation takes approximately 2 to 5 hours.

~! .2 ~ 3 ~ 7 ~ 330 The amount of third-party solvent used for this stage corresponds to that necessary to obtain a medium fluid, that is to say ~ viscosity less than 30 cSt approximately under the reaction conditions.
A particularly favorable variant of realization of the neutralization step consists of carry out this operation in the presence of a catalyst; this catalyst can be halide ions in particular chlorides introduced via chloride ammonium, calcium chloride, zinc chloride COO ~ I ions from carboxylic acids such as ~ ue formic acid, acetic acid, glycoli ~ eu ... or functions NH2 from amines such as polyethylene amines, tristoxa-3 amino-6 hexyl) amine ...; the quantities of catalyst used can range up to 0.1 mole halide ion, COOH ion or NH2 function per mole of alkylphenol.
The 2nd stage, that of total elimination of "carrier" alcohol and water-third-party azeotropic solvent can be carried out if necessary in the presence of an oil of dilution; this step can be omitted if the report carrier alcohol / alkylphenol is sufficiently low, for example between 0.05 and 0.15.
Among the dilution oils can be misas work, we can preferably mention paraffinic oils such as 100 ~ leutral oil; naphthenic oils or mixed can also be used.
The 3rd step, that of carboxylation, is all particularly performed under a pressure of the order of 5 at 15 bar; this operation takes at least 3 hours and usually 5 to 3 p.m. We see that the transformation of phenates into salicylate is not total;
the conditions implemented allow reaching a transformation rate of the order of 20 to 35 ~. A way - ~ 2 ~ 37 ~ 330 - 4a -to increase this transformation rate is to carry out several stages of carboxylation, each stage of carboxylation being preceded by a neutralization step performed under similar conditions ~ that of the 1st step described above and a distillation step similar to that of the 2nd stage developed above. We can thus arrive at a rate of conversion of phenate to salicylate up to 45%; we found that it is no need to exceed this rate to prepare additives presenting the improvements sought.

37 ~
The 4th stage, that of sulfurization-over-alkalization is to pre $ erence carried out at a temperature of the order of 140 to 160 C
for about 3 to 6 hours; like the neutralization step, it can be, if desired, carried out in the presence of a catalyst such as halide ions, COOH or amine functions in quantity up to 0.1 mole of halide ion, COOH or amine function per mole of starting alkylphenol.
An alternative embodiment of this fourth step consists of to split the sulfurization and the over-alkalization into two stages:
- one of sulfurization of the alkylphenate-alkylsalicylate mixture obtained by elemental sulfur in the presence of an alkali hydroxide as a catalyst at a temperature between 140 and 230C, preferably between 140-160C, and a third solvent forming a azeotrope with the reaction water chosen from hydrocarbons aliphatics, aromatic hydrocarbons and point alcohols boiling above 120C and preferably above 150C, the quantities of reagents used corresponding to the ratios following molar ports:
. starting sulfur / alkylphenol ranging from 0.7 to l, S
. alkali hydroxide / alkylphenol starting allsnt 0.01 at 0.03;
- one of over-alkalinization of the sulfurized alkylphenate mixture -sulfurized alkylsalicylate by addition of an alkaline earth base at a temperature of 50 to 80C in the presence of an alkylene glycol and a third solvent forming an azeotrope with the reaction water chosen from aliphatic hydrocarbons, hydrocarbons aromatics and alcohols with a boiling point above 120C
and preferably higher than 150C, the quantities of reagents used in use corresponding to the following molar ratios:
. total alkaline earth base / alkylphenol starting from 1.7 at least and preferably 1.7 to 2;
. alkaline earth base of alkalinization / alkylene glycol ranging from 1 to 1.6 then carbonation of the medium obtained by carbon dioxide at a temperature of 100-185C and under a pressure close to the atmospheric sion, the quantity of C02 used being included between that which can be completely absorbed by the environment reaction and an excess of 30% of this amount.

~ 2r ~ 7 ~ 33 ~ 3 By "total alkaline earth base" is meant the amount total of alkaline earth base (s) used to produce all stages; by "alkaline earth base of over-alkalization "that occurring at the stage of sul ~ urisation-over-alkalization.
According to the variant embodiment, the sulfurization is preferably carried out in the presence of potash or soda as catalyst; this operation generally lasts from 3 to 6 hours; the quantity of third-solvent used corresponds to that necessary to obtain a fluid medium, that is to say of viscosity less than approximately 30 cSt under the reaction conditions.
The actual carbonation is favorably carried out at a temperature of 145-180 C under a pressure of 930 102 to 1010 Pa about.
The carbonated product can optionally be hydrolyzed by a water-third solvent mixture at a temperature of the order of 90-110C
in order to obtain a fluid medium, that is to say of viscosity less than 30 cSt.
After carbonation, dilution oil is introduced in quantity such as the quantity of oil contained in the product final (i.e. after stages 6 and 7 of distillation and filtration) represents from 25 to 65% by weight of said product and preferably 30 to 50% by weight of said product.
The additives which are the subject of the invention have a high basicity; the TBN of additives based on calcium salts by example easily reaches 250 to 300.
The amount of additive to use to improve the properties detergent-dispersing lubricating oils is a function of the future use of said oils.
So for an oil for gasoline engines, the quantity of additive to be added is generally between 1 and 3% by weight; for a diesel engine oil, it is generally between 1.5 and 5% by weight, for an engine oil sailor, it is generally between 10 and 30 ~.
Lubricating oils that can be improved in this way can be chosen from a wide variety of lubricating oils, such as naphthenic, paraffinic and lubricating oils 3'7 ~ 33 ~) mixed base, other hydrocarbon lubricants, for example lubricating oils derived from coal products, and synthetic oils, for example alkylene polymers, alkylene oxide type polymers and their derivatives, including alkylene oxide polymers prepared by polymerizing oxide alkylene in the presence of water or alcohols, for example alcohol ethyl, esters of dicarboxylic acids, es ~ ers llquides phosphorus acids, alkylbenzenes and dialkylbenzenes, polyphenyls, alkylbiphenyl ethers, polymers of silicon.
Additional additives may also be present in said lubricating oils alongside detergent-dispersants obtained according to the method of the invention; we can cite for example anti-oxidant, anti-corrosion additives, additives ashless dispersants.
The following examples are given for information only and do not can be considered as a limit of the domain and the spirit of the invention.

Neutralization A mixture consists of 2 kg of paradodecylphenol (DDP) t7,6 moles) and 500 kg of 2-ethylhexanol (2EH), 390 g of lime Ca ~ OH) 2 to 52.7% calcium (or 5.15 moles).
The medium is brought to 80C and then introduced over 2 hours mixture of 225 g of glycol and 430 g of 2-ethylhexanol.
The reaction medium is heated at the bottom to 145C; the distillation of the azeotrope water-2-ethyl hexanol starts around 30 mn after the start of the addition of the glycol-ethyl-2-hexanol mixture and continues for about 2 hours.
The reaction is allowed to proceed for 4 hours to completely dehydrate the medium.
225 g of Dl distillate containing 76% by weight are recovered of water.
At the end of the reaction, the temperature at the bottom reaches 195C.
The product obtained is cooled to about 150C, then a ~ all 760 g of 100 Neutral oil.

~ ~ 7 ~ 330 The remaining 2-ethylhexanol and the glycol are removed by distillation at 195C at 2666 Pa.
3150 g of product solution are recovered.
Carboxylation We transfer 2 kg of the solution obtained (which corresponds to a quantity of starting DDP of 4.8 moles) in an autoclave of 3.6 liters. The mixture is heated up to 140C while sweeping the reactor with nitrogen for 5 to 10 minutes, then by purging with 10 to 15 g of CO2.
We start to introduce C02 and we increase the pressure

5 min up to 15 bar.
The introduction of C02 lasts 5 hours at 145C.
The amount of CO 2 introduced is 230 g.
The mixture is degassed with stirring, the temperature decreasing gradually, the reactor is purged with nitrogen at the end of degassing, then the product is drawn off at around 100C.
2220 g of a mixture are then recovered, having the characteristics following:
% calcium: 6.16 % C2: 5'74 which corresponds to a conversion rate of the alkylphenate expressed as alkylphenol, as alkylsalicylate expressed as alkyl-salicylic 17%.
Sulfurization-overalkalinization 1600 g of the solution obtained are transferred to a 5-flask liters, fitted with a stirring system, a column, a receiver9 and potash traps.
The following are introduced with stirring at 65 ° C.:
- 350 g of ethyl-2-hexanol - 300 g of Ca (OH) 2 to 52.7% of Ca - 118 g of sulfur The charged device is put under slight vacuum (960 102Pa) and the heating is increased.
When the temperature reaches 130C we introduce in 20 minutes 200 g of ethylene glycol while allowing the temperature to rise.
Around 150C, distillation and bubbling of H2S began in the traps.

~ 2 ~ 3 ~ 7 ~ 3V

The temperature is then left for 1 hour at 155C; she is gradually pore at 1 ~ 5C while 350 g of 2-ethyl hexanol are introduced to thin the mixture.
The temperature is maintained for 1 hour at 165C.
205 g of distillate containing approximately 40% water are recovered.
44 g of H2S are fixed in the traps.
The contents of the flask are then carbonated by bubbling C02 (65 l / hour) for 1 hour at 165C.
84 g of C02 are thus fixed on the product with a yield 63% carbonation.
The mixture is then brought to 195C under 960 10 Pa; a part of 2-ethyl hexanol distilled.
440 g of 100 Neutral oil are introduced and then 0.8 g of antifoam and the vacuum is gradually increased.
Distillation is almost complete when the temperature ture reached 195-200C under 27 102 _ 40 102Pa.
These conditions are maintained for another 1 hour.
2370 g of product are obtained, the characteristics of which are the following :
Gross sediment%: 1.8 Total%: 11 C2%: 7.3 `
S%: 3.1 TBN: 305 The products whose characteristics appear in the table IV were obtained by carrying out:
~ the neutralization step under the same conditions of temperature and pressure as in Example 1, using the quantities of reagents listed in Tables Ia and Ib;
- the carboxylation step under conditions identical to those of Example I (Table IIa);
- the sulfurization-over-alkalization stage under conditions identical to those of Example I ~ Tables IIIa and IIIb).

All the operations described in Example 1J are repeated.
only modifications consisting:

,;
:
, o - introduce 55 g of ammonium chloride (1.08 mole) at the same time while the 390 g of lime in the neutralization stage;
- to be carboxylated for 10 hours instead of 5 hours.
The characteristics of the product are given in Table IVa.

We repeat all the operations described in Example 1, the only modification consisting in replacing the 390 g of lime by 293 g of CaO, the sulfurization-over-alkalization operation being made of lime.
The characteristics of the product are given in Table IVa.

Neutralization The neutralization step described in Example 1 is carried out under the same conditions of temperature and pressure and in using the following reagents:
- a mixture of 1375 g of paradodecylphenol (5.25 moles) and 593 g of a linear alkylphenol of molecular weight of iron 430 (1.38 moles);
- 351 ~ lime - 500 ~ 320 g of 2-ethylhexanol - 200 g glycol - 660 g of oil 2917 g of product solution are recovered.
Carboxylation The carboxylation operation is carried out in the same conditions that in example 1, the only modification consisting in carboxylate for 10 hours instead of 5 hours.
Sulfurization-overalkalinization 2100 g of the solution obtained are transferred to a flask; we add thereto with stirring at 65 ° C.:
- 350 g of 2-ethylhexanol - 314 g of CaCOH2 with 52.7% calcium - 120 g of sulfur.
The loaded device is placed under slight vacuum (960 102Pa).
Heating is increased. At 155C, 200 g of glycol are added in 30 minutes while the temperature continues to rise. The mixture . , 7 ~ '30 becomes more viscous and after 1 hour at 155C the temperature is pro ~ ressively brought to 165C and 350 g of 2-ethylhexanol are introduced.
220 g of distillate containing 128 g of water are recovered; 40 g of H2S are trapped.
The mixture is then carbonated at 165C for 75 minutes and 68 g of CO2 are fixed.
After dis ~ illation of the solvent, 2400 g of product are obtained.
following features:
- gross sediment%: 2.2 - total calcium%: 10.47 - TBN: 283 C2% 6.58 - S%: 2.63 Neutralization To a mixture consisting of 2 kg of dodecylphenol (7.6 moles) and 825 g of cyclohexane, 390 g (5.15 moles) of lime are added and 225 g glycol.
The reaction medium is heated to 95C at the bottom until start of water / cyclohexane distillation.
During the whole neutralization period (7 hours) we keeps the temperature slightly above the temperature of boiling cyclohexane.
146 g of distillate are recovered.
70 g of 100 Neutral oil are added to the medium.
Cyclohexane and glycol are removed by distillation at 195C under 2666 Pa.
3035 g of product solution are recovered.
Carboxylation The carboxylation step is identical to that of exe ~ ple 1.
Sulfurization-overalkalinization The sulfurization-over-alkalization stage is identical to that of Example 1, the solvent used being the same, namely 2-ethyl hexanol.
The characteristics of the product obtained are shown in the table.
IVa.

-.:

'S ~ 7 ~ 3 ~ '30 Neutralization To a mixture consisting of 2 kg of dodecylphenol (7.6 moles) and of 825 g of xylene, we have ~ 390 g of lime (5.15 moles) and 225 g glycol.
The reaction medium is heated at the bottom to 120C, temperature at which distillation of the azeotrope starts water / xylene. After 6 hours of reaction, 178 g of dis-tillat, the temperature at the bottom then reaches 157C.
760 g of 100 Neutral oil are added.
Xylene and glycol are removed by distillation at 195C
under 2666 Pa.
3060 g of product solution are recovered.
Carbox lation Y __ The carboxylation step is identical to that of Example 1.
Sulfurization-overalkalinization The sulfurization-over-alkalization stage is identical to that of Example 1, the solvent used being the same, namely 2-ethyl hexanol.
The characteristics of the product obtained are shown in the table.
IVa.

In a solution of 298 g of CaO in 1143 g of xylene, we added 170 g of methanol. This solution is left to reflux ~ 68C) for 3 hours. A mixture containing 2000 g of DDP and 380 g of xylene is added to it in 2 hours.
At the end of the addition, 38 g of NH4Cl and the medium are added.
reaction is maintained at reflux for 2 hours.
The solvents are then distilled in the following manner: 1st fraction up to 100 ~ C at the top: essentially 2nd fraction methanol up to 127C at the head: mainly xylene.
About 760 g of xylene are left in the medium.
Carboxylation The carboxylation is identical to that of Example 1.

~ ~ 7 ~ 33 (~

We recover a product with the following characteristics:
-% Ca: 5.85 C2 1.92 - conversion rate of DDP 17%
Sulfurization-overalkalinization This step is carried out as in Example 1 from 1600 g of solution obtained.
The product characteristics are shown in Table IVa.

Neutralization The neutralization step is carried out under the conditions of Example 6.
Carboxylation 2 kg of the solution obtained are transferred to a flask. The mixture is heated to 140C while sweeping the reactor by nitrogen for 5 to 10 minutes and then purging it with 10 to 15 g of C02.
We start to introduce C02 and we increase the pressure 5 minutes up to 5 bar ~
The introduction of C02 lasts 5 hours at 142C.
The amount of CO 2 introduced is 100 g.
After degassing of the mixture and purging of the reactor, it is recovered 2115 g of a mixture having the following characteristics:
-% calcium: 6.2 ~% C2 2.7 - transformation rate of DDP: 6%
Sulfurization-overalkalinization The sulfurization-over-alkalization stage is identical to that of Example 1.
The characteristics of the product obtained are shown in the table.
IVa.

-Neutralization The neutralization step is carried out under the conditions of Example 6.

~ ~ 37 ~ 330 Carboxylation 2 kg of the solution obtained are transferred to a balloon; the mixture is heated to 140C while sweeping the reactor by nitrogen for 5 to 10 minutes and then purging it with 10 to 15 g of C02.
We start to introduce C02 and we increase the pressure 5 minutes up to 10 ~ ar.
The introduction of C02 lasts 5 hours at 140C.
The amount of CO 2 introduced is 140 g.
After degassing the mixture and purging the reactor, it is recovered father 2140 g of a mixture having the following characteristics -% calcium: 6.15 2: 3.11 - transformation rate of DDP
Sulfurization-overalkalinization _ The sulfurization-over-alkalization stage is identical to that of Example 1;
The characteristics of the product obtained are shown in the table.
IVa.

Neutralization The neutralization step is carried out under the conditions of Example 8. (use of CaO).
Carboxylation 2 kg of the solution obtained are transferred to a flask; the ~ mixture is heated to 170C while sweeping the reactor by nitrogen for 5 to 10 minutes and then purging it with 10 to 15 g of C02.
We start to introduce C02 and we increase the pressure 5 minutes up to 15 bar.
The introduction of C02 lasts 7 hours at 170C.
The amount of CO 2 introduced is 235 g.
After degassing the mixture and purging the reactor, recovering 2230 g of a mixture having the following characteristics:
-% calcium: 5.95 % C2: 4.22 - transformation rate of DDP: 34%

Sulfurization-overcalcalinisatlon . __. _.
The sulfurization-over-alkalization stage is identical to that of Example 1.
The characteristics of the product obtained are shown in the table.
IVb.

Neutralization-carboxylation To a mixture consisting of 400 g of DDP (1.5 mole) and 165 g of xylene, 112 g of lime (1.5 mole) and 46.5 g of glycol are added.
The medium is heated to the reflux temperature of xylene of so as to allow the distillation of the water / xylene azeotrope. The fraction decanted during the azeotropic distillation represented smells 42 g. It is thus left to reflux for 6 hours so as to have complete dehydration. At the end of the reaction, the temperature ture at the foot reaches 157C.
The solvents are then distilled (150C at the bottom under 107 10 Pa). The distillate represents 165 g. The reaction medium is cooled to 150C and 150 g of xylene are added.
665 g of product are recovered which is carboxylated as in the example ple 1 under the following conditions:
- C02 pressure: 15 bar - Temperature: 140C
- time: 5 hours The product obtained has the following characteristics:
- conversion rate of the DDP: 8.7%
-% Ca: 8 To the product thus obtained, 45 g of lime (0.6 mole) are added and 20 g glycol. The medium is heated to the temperature of reflux of xylene so as to allow the distillation of azeo-water trope ~ xylene. The decanted fraction represents 16.6 g. We let at reflux for 4 hours so as to have dehydration complete. At the end of the reaction the bottom temperature reaches 145 ~ C.
The solvents are then distilled (243 g). The reaction medium nel is cooled and 150 g of xylene are added.
532 g of product are recovered, which is carboxylated in the same conditions than before.
The total amount of C02 introduced during the double carboxylation is 113 g.

The product obtained has the following characteristics:
- DDP transformation rate: 22.2%
-% Ca: 11%
~ C2: 7.5%
Sulfurization-overalkalinization This step is carried out under the conditions described in Example 3 from 530 g of solution.
The product characteristics are shown in Table IVb.

Neutralization The neutralization step is carried out under the conditions identical to those of Example 1.
Carboxylation Carboxylation step is carried out under the conditions identical to those of Example 1.
Sulfurization-overalkalinization 1604 g of solution obtained are transferred to a flask.
The following are introduced with stirring at 65C:
- 350 g of 2-ethylhexanol - 300 g of Ca (OH) 2 - 118 g of sulfur - and 23 g of CaCl2 The charged device is put under slight vacuum (960 10 Pa) and the heating is increased.
When the temperature reaches 130C, 170 g of ethylene glycol are introduced in 20 minutes while allowing the temperature to rise.
Around 150C, distillation and bubbling of H2S began in the traps.
The temperature is then left for 1 hour at 155C; she is gradually brought to 165C while 350 g of 2-ethyl hexanol are introduced to thin the mixture.
The temperature is maintained for 1 hour at 165C and we recover the distillate.
Carbonation is carried out under identical condit ~ ons to those of Example 1.
The recovered product has the following characteristics:
- raw sediments%: 2 - Total ca: 10.6 ,.

7 ~ 330 2: 7 - S%: 2.6 - TBN. 2.98 Neutralization The neutralization step is carried out under the conditions described in Example 6, the only modification consisting of intro-56 g of ammonium chloride at the same time as the 390 g of lime.
Carboxylation The carboxylation operation is carried out under conditions identical to those of Example 1.
Sulfurization-overalkalinization 1562 g of solution obtained are transferred to a flask.
The following are introduced with stirring at 65C:
- 350 g of 2-ethylhexanol - 280 g of lime - 82 g of sulfur.
The charged device is placed under a slight vacuum (960 10 Pa) and the heating is increased. When the temperature reaches 130C, 200 g of ethylene glycol are slowly added in 20 minutes as the temperature continues to rise.
Around 150C, distillation and bubbling of H2S began in the traps, then the temperature is regulated to 155C. The mixture becomes more viscous and after one hour at 155C the temperature rature is gradually brought to 165C while 350 g of ethyl-2 additional hexanol are introduced to refluidify the mixed.
The temperature is maintained for 30 minutes at 165C.
After 1 hour 30 minutes of sulfurization, 200 g of distillate containing 40% water.
Carbonation is carried out under identical conditions to those of Example 1.
The recovered product has the following characteristics:
- raw sediments ~: 2.3 - Total ca: 10.5 ~ 1 2 ~ 7 ~ 30 ~ C2% 7.3 - S%: 2.3 - TBN: 284 Neutralization The neutralization step is carried out under conditions identical to those of Example 18.
Carboxylation Carboxylation step is carried out under conditions identical to those of Example 1 Sulfurization-overalkalinization 1570 g of solution obtained are transferred to a flask.
The following are introduced with stirring at 65DC:
- 300 g of 2-ethyl hexanol - 280 g of Ca (OH) 2 to 52.7% calcium - 94.5 g of sulfur - 22 g NH4Cl The charged device is put under slight vacuum (960 10 Pa) and the heating is increased ~ When the temperature reaches 150C we add 170 g of ethylene glycol in 30 minutes.
The mixture becomes more viscous and after 1 hour at 155C the temperature is gradually raised to 165C while 400 g 2-ethylhexanol are introduced to refluidify the mixture.
The temperature is maintained for 1 hour at 165 ° C. After 2 hours of sulfur ~ 195 g of solvent are distilled including 75 g water; 28 g of H2S are trapped.
The contents of the flask are then carbonated by bubbling C02 (65 l / h). The temperature being maintained at 165C. After a hour 91 g of C02 are fixed with a yield of B6%. We add then 403 g of oil and the solvents are distilled. We get 2348g of product which has the following characteristics:
- raw sediment%: 1.8 - Total Ca%: 10.4 2%: 5.6 - S%: 2.6 - TBN: 284 ~ ~ 7 ~ 330 Neutrallsation The neutralization step is carried out under conditions identical to those of Example 1.
Carboxylation The carboxylation step is carried out under conditions identical to those of Example 1.
Sulfurization-overalkalinization 1568 g of solution obtained are transferred to a flask.
The following are introduced with stirring at 65C:
- 350 g of 2-ethylhexanol - 285 g of lime with 52.7% calcium - 136 g of sulfur The charged device is put under slight vacuum (960 102Pa) and the heating is increased. When the temperature reaches 130C we add 200 g of ethylene glycol in 20 minutes while the temperature continues to rise.
Around 150C, distillation and bubbling of H2S began in the traps then the temperature is regulated at 155C.
The mixture becomes more viscous and after 1 hour 30 minutes at 155C
the temperature is gradually brought to 165C while 350 g additional 2-ethylhexanol are introduced to refluidify The mixture.
The temperature is maintained for 1 hour 30 minutes at 165C. After 3 hours of sulfurization, 215 g of distillate containing 95g of water. 55g of H2S are fixed in the traps.
Carbonation is carried out under identical conditions to those of exe ~ ple 1.
The recovered product has the following characteristics:
- raw sediment%: 1.7 - Total Ca%: 10.8 ~ C2%: 7.1 - S ~: 4 - TBN: 291 E ~ EMPLE 21 Neutralization The QSt neutralization step identical to that of Example 6 ~ 2 ~ 7 ~ 3 ~ '30 Carbox lation , Y
The carboxylation step is identical to that of Example 1.
Sulfurization-overalkalinization 2000 g of solution obtained are transferred to a flask.
The following are introduced with stirring at 65C:
- 300 g of Ca (OH) 2 - 103 g of sulfur - 350 g of 2-ethylhexanol in 30 minutes.
The charged device is placed under slight vacuum (960 lO Pa) and the heating is increased. When the temperature reaches 150C we add 250 g of ethylene glycol in 30 minutes.
The temperature is regulated at 155C.
The mixture becomes more viscous and after 1 hour at 155C the temperature is gradually raised to 165C while 350 g additional 2-ethylhexanol are introduced to refluidify The mixture.
The temperature is maintained at 165C per hour. At the end of these 2 hours of sulfurization, 247 g of distillate containing 98 g of water.
The contents of the flask are then carbonated by bubbling C02 (65 l / h), the temperature being maintained at 165C, 92 g of C02 are fixed with a yield of 68%.
The solvents are partially distilled (460 g of ethyl-2 distilled hexanol).
The flask is cooled below 100C and 75 g of water are added with vigorous stirring at the same time as 2-ethyl hexanol.
After final distillation under 2700 Pa the product has the following features:
- raw sediments%: 2 2%: 7 - Total Ca%: 11 - S%: 2.6 - TBN: 310 The neutralization and carboxylation steps are carried out as described in Example 1.

~ 2 ~ 7 & 30 Sulfurization 1600 g of the solution obtained are transferred to a 5-flask liters, fitted with a stirring system, a column, a refrigerator rant, receiver and potash traps.
The following are introduced with stirring at 50C:
. 350 g 2-ethyl hexanol . 6.5 g of potash The temperature is gradually raised to 130C and then flows 118 g of sulfur in 20 minutes.
The temperature rises to 180C; we leave the middle to this temperature for 2 h 30 min.
220 g of oil are then added; the temperature drops to 90C.
Overcalalinization 300 g of lime are added and the mixture is heated.
When the temperature reaches 130DC we introduce in 20 minutes 200 g of ethylene glycol while allowing the temperature to rise.
The temperature is then left 1 h at 155C; she is gradually brought to 165C while 350 g of 2-ethyl hexanol are introduced to thin the mixture.
The temperature is maintained for 1 hour at 165C.
205 g of distillate containing approximately 40% water are recovered.
The contents of the flask are then carbonated by bubbling C02 ~ 65 l / hour) for 1 hour at 165C.
84 g of C02 are thus fixed on the product with a yield 68% carbonation.
The mixture is then brought to 195C under 960 10 Pa; a part of 2-ethyl hexanol distilled.
220 g of 100 Neutral oil are introduced and then 0.8 g of antifoam and the vacuum is gradually increased.
Distillation is almost complete when the temperature ture reached 195-200C under 27 10 -40 102Pa.
These conditions are maintained for another 1 hour.
23SO g of product are obtained, the characteristics of which are the following :

33 (: ~

- raw sediments%: 2 - Total Ca%: 10.8 - S%: 3 - TBN: 296 The product whose characteristics appear in Table IV has been obtained by performing:
- the neutralization step under the same temperature conditions and pressure than Example 1, using the amounts of reagents appearing in table If - the carboxylation step at 180C under 5 bar pressure (table llc).
- the ~ sulfurization-carboxylation stage under the conditions of Example 1 with the quantities of product shown in Table 1119.

~ ~ r ~ 7 ~

TABLE Ia (neutralization) DDP g 2000 2000 2000 2000 DDP + AP g 2 EH g 500 + 430 500 + 430 500 ~ 430 500 + 430 Cyclohexane g Xylene g CaO g 390 340 844 390 Ca / DDP (~ AP) mol. 0.7 0 ~ 6 1.5 0.7 Glycol g 225 236 235 470 methanol g glycol / DDP (+ AP) mol. 0.5 0.5 0.5 1 me ~ hanol / DDP (+ AP) mol.

Distillate D1 g 225 180 242 235 Water in ~ 1 g 76 76 89 75 Oil 760 760 1520 760 Product obtained 3150 3080 3576 3080 I!
AP stands for alkylphenol 7 ~ 330 TABLE Ib (neutralization) DDP g 2000 2000 2000 2000 DDP + AP g 2 EH g 500 + 430 500 + 430 500 + 430 500 + 430 Cyclohexane g Xylene g Ca (OH) 2 g 390 390 390 CaO g 293 Ca / DDP (+ AP) mol. 0.7 0.7 0.7 0.7 ! Glycol g 710 115 225 225 methanol g glycol / DDP (~ AP) mol. 1.5 0.25 0.5 0.5 .methanol / DDP (+ AP) mol. l ~ NH4Cl g 1 56 Distillate D1 g 1278 160 235 215 Water in D1 g 73 94 87 ~ 75 Oil; 760,760 ¦760 1,760 Product obtained 3125 3160 j3180 13125 AP stands for alkylphenol . ~ ~

~ .2 ~

TABLEA ~ Ic (neutralization ~ n) ¦ EXAMPLE 9 10 11 12 _ DDP g 2000 2000 2000 DDP + AP g 1375 + 593 2 EH g 500 + 320 ICyclohexane g 825 ¦Xylene g 8251143 + 38 ¦

) 2 g 351 390 390 298 ICa / DDP (+ AP) mol 0.68 0.7 0.7.
¦Glycol g 200 225 225 methanol g 170 glycol / DDP (+ AP) mol. 0.46 0.5 0.5 methanol / DDP (+ AP) mol.
NH4Cl g 38 Distillate Dl g 200 146 178 Water in Dl g 61 50 60 Oil 660 760 '760, 760 .Product obtained 'I2917 3035 3060 3060 I
AP stands for alkylphenol ~ ~ 37 ~ 0 TABLE Id (neutralization) ! EXAMPLE ~ 13 14 15 17 '. l DDP g 2000 2000 2000 2000 ~ DDP + AP g ~ 2 EH g 500 + 430 500 + 430 500 + 430 500 + 430 ~ Cyclohexane g Xylene g 'Ca (OH) 2 g 390 390 j390 CaO g `293 ¦
, Ca / DDP (+ AP) mol. 0.7 0.7 0.7 10.7 ; ~ lycol g 115 115 225 1225 ~ methanol gi glycol / DDP (+ AP) mol. 0.25 0.25 0.5 ¦ 0.5 .methanol / DDP (+ AP) mol.
~ NH4Cl gl , Distil] at Dl g 160 160 215 ~ 225 Au Water in D1 g '94 94 75 176 ~ Oil 760 760 760 ~ 760 IProduct obtained 3,160 13,160 3,125 13,150 AP stands for alkylphenol :::

7 ~

TABLE Ie (neutralization) ¦ EXAMPLE 18 19 20 21 _ DDP g 2000 2000 2000 2000 IDDP + AP g 2 EH g 500 + 430 500 + 430 500 + 430 500 + 430 Cyclohexane g Xylene g Ca (OH) 2 g 390 390 390 390 CaO g Ca / DDP (+ AP) mol. 0.7 0.7 0.7 0.7 Glycol g 115 115 225 115 methanol g.
glycol / DDP (+ AP) mol 0.25 0.25 0.5 0.25 methanol / DDP (~ AP) mol.
NH4Cl g 56 56 Distillate Dl g 180 180 225 160 Water in D1 g 105 105 76 94 Oil 760 760 760 760 Product obtained 3200 3200 3150 3160 AP signlfie alkylphenol ~ ~ r ~ 3û
27 bis TABLE If (neutralization) -¦ EXAMPLE 23 DDP g 2000 DDP + AP g 500 + 430 2 EH g Cyclohexane g Xylene g Ca (OH) 2 g 390 CaO g .Ca / DDP (+ AP) mol. 0.7 Glycol g 56 methanol g glycol / DDP (+ AP) mol 0.12 methanol / DDP (+ AP) mol.
~ H4Cl g ¦Distillate Dl g 150 ¦ Water in Dl g 85 Oil 760 Product obtained 3090 __,. .
AP stands for alkylphenol ~ ~ 37 ~ 330 TABLE IIa (Carboxylation) EXAMPLE _ _ _ 3 4 5 6 7 8.

Product to be carboxylated g20no2000 2000 2000 2000 2000 2000 2000 Temperature C 145 145 145 145 145 145 145 145 Pressioll co2 bar15 15 15 15 15 15 15 15 C2 introduced g 230 230 230 230 230 230 230 230 Duration h 5 5 5 5 5 5 10 5 % Ca 6.16 5.42 116.2 5.95 6.2 6.13 5.9 % C2 5.74 5.1 1 8.5 6.83 79 654.1 3.4 6.2 TT d ~ DDP (+ AP)% 17 16 1 17.14J5 9 1 ~ 16 16.1 TT means ta ~ x of transformation 3'7 ~ 30 TABLE IIb (Carboxylation) he Carboxylated product g 2000 2000 2000 2000 2000 2000 ¦ 2000 2000 Temperature ~ C 145 145 145 145 142 140, 170 145 Pressure C02 bar 15 15 15 155 10 15 15 C2 introduced g 230 230 230 230 100 140 2351 230 Duration h 10 1 5 5 55 5 7 5 % Ca 5.75 6.6 6.2 5.856.2 6.15 5.95: 6.16 ~
% C2 to 5.8 4.5 6.7, 1.921 2.7 3.11 4.22 5.74.
DDP TT (+ AP)% 16.5 ~ 11.7 17 6 11 34 ~ 17 TT stands for transformation rate ~: ' ~ ~ B7 ~ 3C) TABLE IIc (Carboxylation) Product to be carboxylated g20002000200020002000 2000 Temperature ~ C 145 145 145 145 145 180 CO2 pressure bar 15 15 15 15 15 5 C2 introduced g 230 230 230 230 230 230 Duration h 5 5 5 5 5 7 % Ca 6.2 6.26.16 6.26.16 6.6 % C2 2.8 2.85.74 4.15.74 1.7 DDP TT (+ AP)% 17 17 17 14 17 25.7 TT stands for transformation rate TABLEA ~ IIIa (Sulfurization - overbasing) - ._ ~. _.

. . _.
Baking agent g 1600 1600 1600 2 EH g 350 + 350 350 + 350 350 + 350 Glycol g 200 200 60 Lime g 300 300 81 caC12 Y
NH4Cl g S g 118 188 104 Lime t./DDP (+ AP) mol. 1.81 1.73 1.85 Lime s.tDDP (~ AP) mol. 1.13 1.14 0.36 Lime s./Glycol s. mol. 1, 26 1.26 1.13 S / DDP (~ AP) mol. 1.06 1.06 1.06 C2 fixed g 84 83 25 Oil g 440 440 440 Lime t. = total lime Lime s. = overcaling lime Glycol s. = Overkalinization glycol 9 ~ 7 ~ 30 TABLE IIIb (Sulfurization - over-alkalization) .
~. . . .__ v _ . _ _ Baking agent g 1600 1600 1600 2 EH g 350 + 350 350 + 350 350 + 350 Glycol g 200 200 200 Lime g 300 300 300 CaC12 g NH4Cl g S g 118 118 118 Lime t./DDP (+ AP) mol. 1.81 1.81 1.81 Lime s./DDP (+ AP) mol. 1.13 1.13 1.13 Lime s./Glycol s. mol. 1.26 1.26 1.26 S / DDP (~ AP) mol. 1.06 1.06 ltO6 C2 fixed g 85 84 83 Oil g 440 440 440 . _._. _ Lime t. = total lime Lime s. = overcaling lime glycol s. = overbasing glycol ~ ' 37 ~ 33 ~

TABLE IIIc (Sulfurization - over-alkalization) EXAMPLE ~ _ _ _ _ _ _ _.

¦ Greaseproof product g1600 1600 12100 j 2 EH g 350 * 350 350 + 350 1350 + 350 Glycol g 200 200 1200 Lime g 300 300 314 CaC12 g.
NH4Cl g.
S g 118 118 120 Lime t./DDP (+ AP) mol. 1.85 ¦1.85 1.7 Lime s./DDP (+ AP) mol. 1.13 11.13 1 Lime s./Glycol s. mol. 1.26 ~ 1.26 1.31 S / DDP (+ AP) mol. 1.06 '1.06 0.87 C2 fixed g 87 85 68 Oil g 440. 440 440 I
-Lime t. = total lime Lime s ~ = over-alkalinization lime glycol s. = overbased glycol ~ 1 2 ~ 7 ~

TABLE IIId (Sulfurization - over-alkalization) Grease proof g 1600 1600 1600 2 EH g 350 + 350 350 + 350 350 ~ 350 Glycol g 200 200 200 Lime g 300 300 300 CaCl2 g NH4Cl g S g 118 118 118 Lime t./DDP (+ AP) mol.1.81 1.81 1.81 Lime s./DDP (+ AP) mol 1.13 1J13 1.13 Lime s./Glycol s. mol. 1.26 1.26 1.26 S / DDP t + AP) mol. 1.03 1.03 1.03 C2 fi ~ é g 88 91 75 Oil gi ~ 0 44D 4 Lime t. = total lime Lime s. = overcaling lime ~ lycol s. = overbased glycol 3 ~

TABLE IIIe (Sulfurization - over-alkalinization) .
Baking agent 1600 1600 1600 530 2 EH g 350 + 350 350 + 350 350 + 35060 Glycol g 200 200 200 33 Chau g 300 300 3Q0 43 NH4Cl g.

S g 118 11 ~ 118 51 Lime t. jDDP (+ AP) mol. 1.81 1.81 1.81 1.8 Lime s. / DDP (~ AP) mol. 1.13 1.13 1.13 0.38 lime s./glycol s. mol. 1.26 1.26 1.26 1.1 S / DDP (+ AP) mol. 1.06 1.06 1.06 1.06 C2 fixed g 83 80 82 20 Oil g 44 440 440 440 Lime t. = total lime Lime s. = overcaling lime glycol s. = over-alkalinized glycol ~ ion : -:
:

TABLE IIIf (Sulfurization - overbasing) Grease proof g1600 1562 1570 2 EH g 350 + 350 350 + 350 300 + 400 Glycol g 170 200 170 Lime g 300 280 280 CaCl2 g 23 NH4Cl g 22 S g 118 82 94.5 Lime t./DDP (+ AP) mol. 1.81 1.83 1.83 Lime s. / DDP (+ AP) mol. 1.13 1.13 1.13 Lime s./Glycol s. mol. 1.48 1.17 1.38 S / DDP (- ~ AP) mol. 1.06 0.77 0.85 C2 fixed 8 89 90 91 Oil g ~ 403.

Lime t. = total lime Lime s. = overcaling lime glycol s. = overbased glycol ~ ~ '7 ~

TABLE IIIg (sulfurization - 6uralcalinization) _ _ _.

Greaseproof product g 1568 Z000 1600 2 EH g 350 + 350 350 + 350 350 ~ 350 Glycol g 200 250 240 Tab2 g 285 300 300 NH4Cl g '.
S g 136 103 118 Lime t./DDP (+ AP) mol. 1.82 1.81 1.8i Lime s./DDP (+ AP) mol. 1.13 1.13 1.13 Lime s./glycol s. mol. 1.2 1 1.05 S / DDP (+ AP) mol. 1.25 0.74 1.03 C2 fixed g 77 92 106 Oil g 440 440 Lime t. = total lime Lime s. = overcaling lime glycol s. = overbased glycol ~ ~ 3 ~ 7 ~ 3 ~ 30 TABLE IVa (Characteristics of the final product) Gross sediment% 1.8 1.7 2 2 2.5 1.8 1.7 Total Ca% 11 10.5 10,810.7 10,710.6 10.7 C2% 7.3 7 6.9 7.6 8.7 6.1 5.8 S% 3.1 3 3 3 3 3.1 3.1 _ _ .

Gross sediment% 1.9 2.2 1.9 2 1.9 1.9 2 Total Ca% 10.5 10.47 10.75 10,710.7 10.9 10 ~ 8 C2% 7.4 6.58 6.4 7.4 5 5.5 5.2 S ~ 3 2.63 3 3 3 3 3 _. _ _ I

~ ~ 7 ~ 30 TABLE IVb (Characteristics of the final product) , _ Gross sediment% 1.9 2.2 2 2.3 1.8 1.7 2 2 2.1 Total 2 10.6 10, B10.6 10.5 10.4 10.8 11 10.8 10.1 C2% 6.2 ~, 1 7 7.3 5.6 7.1 7 7 6.2 S ~ 1 2.9 2.9 2.6 2.3 2.6 4 2.6 3 2.9 TBN ~ 297 Z89 298 284 L ~ 310 296 234, .
:

Claims (11)

1. Overbased detergent-dispersant additives for lubricating oils, characterized in that they are obtained by:
a) neutralization of an alkylphenol carrying one or several C8-C30 alkyl substituents, using a base alkaline earth in the presence of a selected "vector" alcohol in the group consisting of C1-C3 monoalcohols, alkylene glycols and alkoxyalkanols of formula R (OR ') xOH
where R is a C1-C4 alkyl radical, R 'is an alkyl radical in C2-C3 and x is equal to 1 or 2, and a solvent forming an azeotrope with the reaction water, chosen from the group consisting of aromatic or aliphatic hydrocarbons boiling point above 70 ° C and alcohols boiling point above 120 ° C, said operation of neutralization being carried out at a temperature at least equal to that of formation of the azeotrope, the amounts of reagents used corresponding to the molar ratios following:
. alkaline earth / alkylphenol base ranging from 0.5 to 2 . "carrier" alcohol / alkylphenol ranging from 0.05 to 3;
b) distillation under nitrogen sweep of the medium reaction obtained until total elimination of the alcohol "vector" and azeotrope;
c) carboxylation of the alkylphenate formed into alkyl-salicylate using carbon dioxide at a temperature of 100 to 185 ° C at a pressure of at least 5 bar for at least 3 hours in the presence of a dilution oil or a solvent aromatic, the amount of CO2 corresponding to that required to obtain a transformation rate expressed in acids from alkylphenate to alkylsalicylate between 5 and 30%; or d) sulfurization-over-alkalization of the alkyl mixture phenate-alkylsalicylate obtained by elemental sulfur in presence of an alkaline earth base, of an alkylene glycol and a solvent chosen from the group consisting of aromatic hydrocarbons, aliphatic hydrocarbons and alcohols with a boiling point above 120 ° C, a temperature of the order of 140 to 230 ° C, the quantities of reagents used corresponding to the molar ratios following:
. starting sulfur / alkylphenol ranging from 0.7 to 1.5 . total alkaline earth base / alkylphenol from starting at least 1.7 . alkaline earth base of overbasing / alky-lene glycol ranging from 1 to 1.6;
then carbonation of the medium obtained by carbon dioxide at a temperature of 100-185 ° C and under similar pressure of atmospheric pressure, the amount of CO2 used being between that which can be completely absorbed by the reaction medium and an excess of 30% of this amount;
or d ') sulfurization of the alkylphenate- mixture alkylsalicylate obtained by elemental sulfur in the presence of an alkali hydroxide as a catalyst at a temperature between 140 and 230 ° C, and a solvent forming an azeotrope with the reaction water, chosen from the group consisting of aliphatic hydrocarbons, hydrocarbons aromatic bures and higher boiling alcohols laughing at 120 ° C, the quantities of reagents used corresponding to the following molar ratios:
. starting sulfur / alkylphenol ranging from 0.7 to 1.5 . starting alkali hydroxide / alkylphenol ranging from 0.01 to 0.03; and d '') over-alkalinization of the alkylphenate mixture sulfurized-alkylsalicylate sulfurized by addition of a base alkaline earth at a temperature of 50 to 80 ° C in the presence an alkylene glycol and an azeo-forming solvent trope with reaction water, chosen from the group consisting by aliphatic hydrocarbons, aromatic hydrocarbons matics and alcohols with a boiling point higher than 120 ° C, the quantities of reagents used correspond with the following molar ratios:
. total alkaline earth base / starting alkylphenol at least 1.7 . alkaline earth base of overbasing / alky-lene glycol ranging from 1 to 1.6 then carbonation of the medium obtained by carbon dioxide at a temperature of 100-185 ° C and under a pressure close to atmospheric pressure, the amount of CO2 used being between that which can be completely absorbed by the reaction medium and an excess of 30% of this amount;
e) elimination by distillation of the alkylene glycol and solvent after addition of dilution oil or well hydrolyzed then elimination by distillation of the alkylene-glycol and solvent after addition of dilution oil;
and f) filtration to remove sediment. 2. Overbased detergent-dispersant additives for lubricating oils, characterized in that they are obtained by:
a) neutralization of an alkylphenol carrying one or several C8-C30 alkyl substituents, using a alkaline earth base in the presence of a "vector" alcohol chosen from the group consisting of C1-C3 monoalcohols, alkylene glycols and alkoxy alkanols of formula R (OR ') xOH where R is a C1-C4 alkyl radical, R' is a C2-C3 alkyl radical and x is 1 or 2, and one solvent forming an azeotrope with the reaction water, chosen from the group consisting of hydrocarbons aromatic or aliphatic with higher boiling point at 70 ° C and alcohols with a higher boiling point 120 ° C, said neutralization operation being carried out at a temperature at least equal to that of formation of the azeotrope, the quantities of reagents used corresponding to the following molar ratios:
. alkaline earth / alkylphenol base ranging from 0.5 at 2 . "carrier" alcohol / alkylphenol ranging from 0.05 to 3;
b) distillation under nitrogen sweep of the medium reaction obtained until total elimination of the alcohol "vector" and azeotrope;
c) carboxylation of the alkylphenate formed into alkyl-salicylate using carbon dioxide at a temperature of 100 to 185 ° C at a pressure of at least 5 bar for at at least 3 hours in the presence of a dilution oil or a aromatic solvent, the amount of CO2 corresponding to that required to obtain a conversion rate expressed as acids from alkylphenate to alkylsalicylate between about 5 and 30%;
d) sulfurization-over-alkalization of the alkyl mixture phenate-alkylsalicylate obtained by elemental sulfur in presence of an alkaline earth base, of an alkylene glycol and a solvent chosen from the group consisting of aromatic hydrocarbons, aliphatic hydrocarbons and alcohols with a boiling point above 120 ° C, a temperature of the order of 140 to 230 ° C, the quantities of reagents used corresponding to the molar ratios following:
. starting sulfur / alkylphenol ranging from 0.7 to 1.5 . total alkaline earth base / alkylphenol de share of at least 7 . alkaline earth base of overbasing / alky-lene glycol ranging from 1 to 1.6;

then carbonation of the medium obtained by carbon dioxide at a temperature of 100-185 ° C and under similar pressure of atmospheric pressure, the amount of CO2 used being between that which can be completely absorbed by the reaction medium and an excess of 30% of this amount;
e) elimination by distillation of the alkylene glycol and solvent after addition of dilution oil or well hydrolyzed then elimination by distillation of the alkyl-lene glycol and solvent after addition of dilution; and f) filtration to remove sediment. 3. Additives according to claim 2, characterized in that the quantities of reagents used in step of neutralization correspond to the following molar ratios:
. alkaline earth / alkylphenol base ranging from 0.6 at 1.6 . "vector" alcohol / alkylphenol ranging from 0.1 to 1.5. 4. Additives according to claim 1, characterized in that the sulfurization-over-alkalization stage is split into two stages:
- one of sulfurization of the alkylphenate mixture-alkylsalicylate obtained by elemental sulfur in the presence of an alkali hydroxide as a catalyst at a temperature between 140 and 230 ° C, and a solvent forming an azeotrope with the reaction water, chosen from the group consisting of aliphatic hydrocarbons, hydrocarbons aromatic bures and higher boiling alcohols laughing at 120 ° C, the quantities of reagents used corresponding to the following molar ratios:
. starting sulfur / alkylphenol ranging from 0.7 to 1.5 . starting alkali hydroxide / alkylphenol ranging from 0.01 to 0.03;

- one of over-alkalinization of the alkylphenate mixture sulfurized-alkylsalicylate sulfurized by addition of a base alkaline earth at a temperature of 50 to 80 ° C in the presence an alkylene glycol and an azeotrope-forming solvent with the reaction water, chosen from the group consisting of aliphatic hydrocarbons, aromatic hydrocarbons and alcohols with a boiling point above 120 ° C, quantities of reagents used corresponding to following molar ratios:
. total alkaline earth base / alkylphenol from starting at least 1.7 . alkaline earth base of overbasing / alky-lene glycol ranging from 1 to 1.6 then carbonation of the medium obtained by carbon dioxide at a temperature of 100-185 ° C and under similar pressure of atmospheric pressure, the amount of CO2 used being between that which can be completely absorbed by the reaction medium and a 30% excess of this amount. 5. Additives according to claim 1 or 2, charac-that the quantities of reagents used in the sulfurization-neutralization stage correspond to following molar ratios:
. starting sulfur / alkylphenol ranging from 0.7 to 1.3 . total alkaline earth base / alkylphenol from starting from 1.7 to 2. 6. Additives according to claim 1, 2 or 4, ca-characterized in that the alkaline earth base is hydro-xyde or calcium oxide. 7. Additives according to claim 1, 2 or 3, ca-characterized in that the "vector" alcohol is methanol or glycol. 8. Additives according to claim 1, 2 or 4, ca-characterized in that the solvent is ethyl-2 hexanol, cyclohexane or xylene. 9. Additives according to claim 4, characterized in that the alkali hydroxide used in the step of sulfurization is potash or soda. 10. Additives according to claim 1 or 2, charac-terrified in that the neutralization step and the step of over-alkalization are carried out in the presence of halo ions genures, COOH- or amino function per mole of alkylphenol of departure. 11. Lubricating compositions characterized in that that they contain in a lubricating oil of viscosity 1 to 30% of at least one of the detergent additives-overbased dispersants which are the subject of the claim 1, 2 or 4.