EP0121024B1 - Préparation de sulfonates de calcium surbasiques - Google Patents

Préparation de sulfonates de calcium surbasiques Download PDF

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Publication number
EP0121024B1
EP0121024B1 EP19830307343 EP83307343A EP0121024B1 EP 0121024 B1 EP0121024 B1 EP 0121024B1 EP 19830307343 EP19830307343 EP 19830307343 EP 83307343 A EP83307343 A EP 83307343A EP 0121024 B1 EP0121024 B1 EP 0121024B1
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Prior art keywords
oil
mixture
phase
reaction mixture
temperature
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EP19830307343
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German (de)
English (en)
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EP0121024A1 (fr
Inventor
Kenneth Alcock
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ExxonMobil Technology and Engineering Co
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Exxon Research and Engineering Co
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    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
    • C10M159/00—Lubricating compositions characterised by the additive being of unknown or incompletely defined constitution
    • C10M159/12—Reaction products
    • C10M159/20—Reaction mixtures having an excess of neutralising base, e.g. so-called overbasic or highly basic products
    • C10M159/24—Reaction mixtures having an excess of neutralising base, e.g. so-called overbasic or highly basic products containing sulfonic radicals

Definitions

  • This invention relates to the production of overbased calcium sulphonates, and in particular to the reduction of handling problems in the preparation and processing of overbased calcium sulphonates.
  • Overbased calcium sulphonates consist of colloidal calcium carbonate dispersed in an oil, with sulphonate acting as the surfactant. They have been known for some time as additives for automotive crankcase lubricants, their basicity neutralises acids formed in the lubricant; thereby reducing corrosion, and the dispersant effect of the additive helps to inhibit the formation of harmful deposits in the oil.
  • US-A-3318809 describes a similar process in which finely powdered calcium oxide is slurried in methanol and carbonated in a counter-current carbonation unit before being mixed with oil and calcium sulphonate. After mixing the methanol and oil phases are separated, and following stripping the oil phase is treated with water to decompose any methanol complex.
  • US-A-3 342 733 describes a similar process in which a colloidal gel of an alkaline earth metal carbonate in an aqueous medium is mixed with a hydrocarbon oil containing an oil-dispersible surfactant such as a calcium sulphonate to form an emulsion.
  • a colloidal gel of an alkaline earth metal carbonate in an aqueous medium is mixed with a hydrocarbon oil containing an oil-dispersible surfactant such as a calcium sulphonate to form an emulsion.
  • the emulsion breaks on standing and the water phase is removed.
  • US-A-3 258 426 describes an alternative process for preparing calcium carbonate dispersions in oil in which an emulsion is formed of calcium carbamate in oil and the carbamate is then converted to the carbonate by heating. Coarse particles formed in the formation of calcium carbonate are retained in an emulsion which is separated from the oil phase containing the calcium carbonate dispersion.
  • BE 785268 describes a similar process using methanol and a second, volatile hydrocarbon solvent in the mixture that is carbonated at a temperature of up to 35°C. Following carbonation, the mixture is optionally heated to reflux for a short time. After removing volatiles the mixture is again blown with carbon dioxide to complete carbonation.
  • the sludge has a grease-like consistency and also contains a considerable amount of the overbased calcium sulphonate product but in a form which is clearly unsuitable for use as a lubricating oil additive. This reduces the yield of usable product from the preparation. Furthermore, the accumulation of sludge presents a considerable problem in a commercial process since it requires frequent cleaning operations to keep filters and centrifuges operable, while the sludge itself presents considerable disposal problems.
  • GB-A-2097417 describes a process for the preparation of highly basic alkaline earth metal salts in which an alkaline earth metal hydroxide is carbonated in methanol and mixed with a dispersant (as in the early prior art) but then further carbonated, and water and methanol separated from the product.
  • the invention provides a process of preparing an overbased calcium sulphonate comprising:
  • Component (a) of the reaction mixture includes one or more oil-soluble sulphonic acids and these may be natural or synthetic sulphonic acids, e.g. a mahogany or petroleum alkyl sulphonic acid; an alkyl sulphonic acid; or an alkaryl sulphonic acid.
  • the alkyl sulphonic acid should preferably have at least 18 carbon atoms in the alkyl chain.
  • Most suitable are sulphonic acids of molecular weight from 300 to 700, preferably from 400 to 500.
  • Particularly suitable sulphonates are the alkaline earth metal salts of these most suitable sulphonic acids, and a calcium sulphonate is the preferred sulphonate.
  • Component (a) may be conventionally used as a mineral oil solution.
  • a suitable mineral oil solution comprises from 50 to 90% by weight, preferably 70% by weight, of sulphonic acid or sulphonate.
  • Component (b) of the reaction mixture is an aromatic or aliphatic hydrocarbon solvent.
  • Aromatic hydrocarbons are preferred, and examples of these are toluene, xylene and ethyl benzene.
  • Suitable aliphatic hydrocarbons include paraffinic hydrocarbons such as n-hexane, n-heptane, n-decane, n-dodecane, white spirit, naphtha or iso-paraffins.
  • Component (c) is very preferably methanol, although other C 1 to C 5 alcohols such as ethanol can be used.
  • component (a) When component (a) is introduced as an oil solution it may be unnecessary to introduce additional oil-thus, the oil solvent for (a) acts as component (d)-and this is preferred. Alternatively oil may be introduced separately into the reaction mixture.
  • the reaction is thus an oil solution of components (a), (b), (c) and (e).
  • Suitable oils for component (d) include hydrocarbon oils, particularly those of mineral origin. Oils which have viscosities of 15 to 30 cSt at 38°C are very suitable. Alternatively the lubricating oils described later in the specification may be used.
  • Calcium hydroxide used as component (e) will generally be derived from a natural source such as lime or gypsum.
  • the calcium hydroxide (component (e)) may be added in one stage or in two stages. In two stage addition first sufficient calcium hydroxide is added to neutralize the sulphonic acid, and then secondly the excess calcium hydroxide is added. However single stage addition is preferred.
  • Additional reaction promoters may be used and these may be the ammonium carboxylates such as those described in United Kingdom patent GB-A-1 309 172 where the preferred ammonium carboxylates are those derived from C 1 to C 3 saturated monocarboxylic acids, e.g. formic acid, acetic acid or propionic acid.
  • alkali metal salts of a C, to C 3 carboxylic acid may be used, such as those of a C 1 to C 3 saturated monocarboxylic acid.
  • a further alternative promoter is a metal halide or sulphide such as a halide or sulphide of an alkali metal, alkaline earth metal, aluminium, copper, iron, cobalt or nickel.
  • the volume ratio of components (b) and (c) should preferably be between 30:70 and 80:20, otherwise if there is too much of component (b) the resulting product tends to be greasy, whereas with too much of component (c) the reaction mixture may tend to be too viscous during addition of carbon dioxide and any further calcium hydroxide.
  • Preferred volume ratios of (b) and (c) are between 50:50 and 70:30.
  • a promoter we prefer to use less than 10%, e.g. between 3.0% and 7.0% by weight based on the total weight of calcium hydroxide in the reaction mixture, (i.e. including any calcium hydroxide which is added at a later stage in the reaction).
  • the relative quantities of the other components of the reaction mixture are not so critical, but it is preferred that the weight of component (a) is 40% to 220% of the total weight of oil in the reaction mixture; and that the amounts by weight of components (b) and (c) are each between 30% and 160% of the total weight of oil, in the reaction mixture.
  • the carbon dioxide is introduced into the mixture while it is at a temperature below 35°C, preferably not more than 30°C, and more preferably in the range to 23°C to 30°C, in an amount up to from 75 to 95 wt%, preferably 80 to 90 wt%, of that stoichiometrically required to neutralize the excess calcium hydroxide.
  • this low temperature carbonation promotes the reduction of sediment resulting from formation of insoluble carbonates.
  • step ii) comprises:
  • the heating step (iii), hereinafter referred to as "a heat soak” or “heat soaking”, is preferably carried out over a period of from 1/2 to 3 hours, and most preferably over 1 to 2 hours.
  • the temperature preferably does not exceed 55°C, and more preferably does not exceed 45°C and most preferably in the range of 30°C to 45°C.
  • the reaction mixture is desirably stirred. It is believed that the heat soak results in more lime going into solution, which results in greater lime utilization and an increase TBN in the product. In addition lower viscosity products may be obtained for a given TBN. Better yields and/or a reduced skinning tendency and/or a reduction in the problems of sediment resulting from unreacted materials may also be obtained.
  • Diluent oil may be added either to the reaction mixture following heat soaking in step iii) or to the recovered second phase of step iv) to give the required dilution to the additive product or at both stages. Addition of at least part of the oil following step iii) is believed to improve subsequent centrifugation steps. Oil is preferably added to give a product containing from 25 to 75 wt% overbased calcium sulphonate.
  • the reaction mixture is separated into two phases in step iv) and this is found to reduce the tendency to sludge formation in the product.
  • the separation may be done by gravity-thus, by leaving the reaction mixture to stand-or by mechanical means such as centrifugation or decantation in a scroll decanter. This separation is preferably carried out between ambient temperature and 60°C, more preferably at a temperature not exceeding 45°C.
  • the first, upper layer comprises alcohol and water formed during the reaction, with possible minor amounts of the hydrocarbon solvent and neutral calcium sulphonate.
  • the second, lower layer comprises the desired overbased calcium sulphonate in the oil with possible minor amounts of alcohol and water and any sediment.
  • the phases are separated and the second phase is treated further to recover the desired product.
  • the first phase may be treated to recover the alcohol, which may then be recycled.
  • the second phase may be heated to an elevated temperature, e.g. above 130°C, and/or reduced pressure to remove volatile materials (components (b), water and any remaining alcohol) and is preferably thereafter filtered and/or centrifuged to remove solids. Filtering may be enhanced using conventional filter aids. The desired overbased detergent additive is obtained as the filtrate.
  • step (iv) it is possible for a single centrifugation step to be employed to carry out the phase separation of step (iv) with a simultaneous solids removal.
  • Three phase centrifuges are available capable of carrying out such a liquid-liquid-solid separation.
  • the process of the invention enables a high quality, high TBN calcium sulphonate product to be obtained in good yields with reduced amounts of material losses in sludge and/or sediment and reduced problems in waste disposal which can arise when large amounts of sludge or flocculent material are produced.
  • the process of the invention in particular provides a means of preparing a preferred product with a TBN of at least 300 mg (KOH)/g at a kinematic viscosity measured at 100°C of less than 90 cSt, more preferably less than 70 cSt.
  • the process enables such products to be prepared such that in the final filtration of the product a preferred filtration rate of at least 200 IIhm 2 , more preferably at least 400 I/hm 2 , is achieved.
  • preferred aspects of the process enable low haze, high stability products to be obtained.
  • the overbased detergent of this invention is suitable for use in lubricating oils, both mineral and synthetic.
  • the lubricating oil may be an animal, vegetable or mineral oil, for example petroleum oil fractions ranging from naphthas or spindle oil to SAE 30, 40 to 50 lubricating oil grades, castor oil, fish oils or oxidised mineral oil.
  • Suitable synthetic ester lubricating oils include diesters such as di-octyl adipate, dioctyl sebacate, didecyl azelate, tridecyl adipate, didecyl succinate, didecyl glutarate and mixtures thereof.
  • the synthetic ester can be a polyester such as that prepared by reacting polyhydric alcohols such as trimethylolpropane and pentaerythritol with monocarboxylic acids such as butyric acid, caproic acid, caprylic acid and pelargonic acid to give the corresponding tri- and tetra-esters.
  • complex esters may be used as base oils such as those formed by esterification reactions between a dicarboxylic acid, a glycol and an alcohol and/or a monocarboxylic acid.
  • Blends of diesters with minor proportions of one or more thickening agents may also be used as lubricants.
  • the amount of overbased detergent added to the lubricating oil should be a minor proportion, e.g. between 0.01% and 10% by weight, preferably between 0.1% and 5% by weight.
  • the final lubricating oil may contain other additives according to the particular use for the oil.
  • viscosity index improvers such as ethylene propylene copolymers may be present as may succinic acid based dispersants, other metal containing dispersant additives and the well known zinc dialkyldithiophosphate antiwear additives.
  • the invention extends to an additive concentrate comprising an oil solution of an overbased calcium sulphonate of the invention and preferably one or more additional additives. It also extends to a lubricating oil containing the overbased calcium sulphonate.
  • the amount of carbon dioxide added to the above mixture was 356 g-i.e. 88 wt% of the stoichiometric amount required by the overbasing amount of lime-charged over 3.64 hours. Where different amounts are added the overall charge time for C0 2 is the same.
  • Diluent oil is added to the carbonated product, unless otherwise indicated, in an amount of 875 g.
  • Stanco 150 is used as the diluent oil.
  • sludge is used to describe a heavy layer formed within the product which is hazy in appearance and has a grease-like consistency when filtered off the product. It is to be distinguished from particulate sediments which generally comprise calcium carbonate and/or neutral calcium sulphonate and which are deposited from the product as hard or soft precipitates. On filtering the sediments form a filter cake, while any sludge is deposited as a greasy layer on top.
  • the soap content was measured by the technique described in ASTM D3712.
  • Foaming tendency was measured on a solution of 2.0 wt% of the filtrate in diluent oil by the technique described in ASTM D892 Seq I using 400 ppm of Dow Corning D200 silicone as anti-foaming agent, unless otherwise indicated.
  • Blend stability was measured by observing a) the volume percentage of sediment formed after mixing the sample with heptane in a 1:1 (v/v) ratio and centrifuging for 20 minutes; and (b) the volume percentage of sediment formed after the sample/heptane mixture is left to stand for 24 hours.
  • Comparative Examples C and D use a phase separation step but in conjunction with a high temperature carbonation, and the product still contains some sludge, has poor filterability and poor blend stability.
  • Comparative Examples E-J show no sludge formation but the products have poor filterability and/or poor blend stability and/or high viscosity.
  • Comparative Example J includes both phase separation and heat soaking step but employs a high temperature carbonation. The results are to be compared to those for Example 1, which is a similar process except that the low temperature conditions of the invention are employed.
  • Example 1 gives excellent filterability and a much lower viscosity.
  • Examples 2 to 6 show the effect of variations from the preferred procedure of Example 1; in each case the product is free from sludge and where measured the viscosity is much lower than Comparative Example J. Examples 2 and 4 show reduced filterability but these results were obtained without a centrifugation step between phase separation and filtering and this would be expected to make filtration difficult. Examples 3 to 5 also show that carbonation beyond 90% of stoichiometric results in a less optimum product, and Example 6 shows that two part lime is less advantageous but the product of this Example shows improved blend stability as compared to Comparative Examples E-H which also use two part lime addition.
  • Haze was measured as the amount of light scattering determined using a nephalometer (Coleman Photonephelometer available from Coleman Instruments Company of USA). The measurements are carried out on a 5 wt% solution in diluent oil and the results are expressed in nephalos.
  • Carbonation was carried out over 3 hours, but still to 90% of the stoichiometric amount required by the overbasing lime.
  • the lime, most of the toluene and methanol were charged to the reactor, and then the sulphonic acid and remaining toluene was added.
  • the reactor was cooled to 25 ⁇ 2°C.
  • Example 12 The procedure of Example 12 was repeated using Balthazard Lime in place of US Gypsum lime. To provide a comparison this preparation was repeated without heat soaking (Comparative Example K) and without phase separation (Comparative Example L).

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Organic Chemistry (AREA)
  • Lubricants (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Claims (9)

1. Procédé de production d'un sulfonate de calcium rendu surbasique, consistant:
i) à former un mélange
(a) d'un acide sulfonique ou d'un sulfonate de métal alcalino-terreux soluble dans l'huile,
(b) d'un solvant hydrocarboné aromatique ou aliphatique,
(c) d'un alcool en Ci à C5,
(d) d'une huile, et
(e) d'un excès d'hydroxyde de calcium par rapport à la quantité nécessaire pour réagir avec l'acide sulfonique présent;
ii) à carbonater le mélange à une température n'excédant pas 35°C avec 75 à 95% en poids de C02 sur -la base de l'hydroxyde de calcium en excès;
iii) à chauffer le mélange réactionnel après carbonatation, caractérisé en ce que dans l'étape (iii), le mélange réactionnel est chauffé à une température ne dépassant pas 60°C pendant une période n'excédant pas 15 minutes; après quoi le procédé consiste:
iv) à diviser le mélange carbonaté en une première phase comprenant au moins une quantité dominante de l'alcool et une deuxième phase comprenant au moins une quantité dominante du solvant hydrocarboné et de l'huile, et à éliminer la première phase; et
v) à chasser la matière volatile de la seconde phase pour obtenir une dispersion dans l'huile de sulfonate de calcium rendu surbasique.
2. Procédé suivant la revendication 1, dans lequel l'étape (ii) consiste:
ii) à carbonater le mélange à une température n'excédant pas 30°C.
3. Procédé suivant la revendication 1 ou la revendication 2, dans lequel l'huile de dilution est ajoutée après l'étape (iii) et/ou après l'étape (v).
4. Procédé suivant l'une quelconque des revendications 1 à 3, dans l'étape (iii) duquel le mélange réactionnel carbonaté est chauffé à une température n'excédant pas 55°C pendant 0,5 à 3 heures.
5. Procédé suivant la revendication 4, dans lequel le mélange réactionnel carbonaté est chauffé à une température de 30 à 45°C.
6. Utilisation d'une dispersion de sulfonate de calcium rendu surbasique telle qu'obtenue par le procédé suivant l'une quelconque des revendications 1 à 5 comme additif pour huile lubrifiante.
7. Huile lubrifiante comprenant une dispersion de sulfonate de calcium rendu surbasique telle que produite par le procédé suivant l'une quelconque des revendications 1 à 5.
8. Concentré d'additif destiné à être mélangé avec une huile lubrifiante, comprenant une solution dans l'huile d'une dispersion de sulfonate de calcium rendu surbasique telle que produite par le procédé suivant l'une quelconque des revendications 1 à 5.
EP19830307343 1982-12-08 1983-12-02 Préparation de sulfonates de calcium surbasiques Expired EP0121024B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8235018 1982-12-08
GB8235018 1982-12-08

Publications (2)

Publication Number Publication Date
EP0121024A1 EP0121024A1 (fr) 1984-10-10
EP0121024B1 true EP0121024B1 (fr) 1987-03-18

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EP19830307343 Expired EP0121024B1 (fr) 1982-12-08 1983-12-02 Préparation de sulfonates de calcium surbasiques

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EP (1) EP0121024B1 (fr)
JP (1) JPS59139354A (fr)
BR (1) BR8306730A (fr)
CA (1) CA1205819A (fr)
DE (1) DE3370356D1 (fr)
SG (1) SG67087G (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0737625B2 (ja) * 1990-08-31 1995-04-26 株式会社松村石油研究所 高塩基性カルシウムスルホネートの製造方法
GB9120038D0 (en) * 1991-09-19 1991-11-06 Exxon Chemical Patents Inc Overbased metal-containing detergents
US6239309B1 (en) * 1999-12-21 2001-05-29 Chevron Oronite S.A. Synthesis of an overbased detergent from sludge coming from the production high BN overbased alkylaryl sulfonate or overbased sulfurized alkylphenate

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3830739A (en) * 1970-07-17 1974-08-20 Witco Chemical Corp Preparation of hyperbasic dispersions
DE2861618D1 (en) * 1977-07-04 1982-03-18 Exxon Research Engineering Co The production of highly basic calcium sulphonates.
GB2082619A (en) * 1980-08-29 1982-03-10 Exxon Research Engineering Co Basic calcium sulphonate

Also Published As

Publication number Publication date
CA1205819A (fr) 1986-06-10
BR8306730A (pt) 1984-07-17
DE3370356D1 (en) 1987-04-23
EP0121024A1 (fr) 1984-10-10
JPH0469200B2 (fr) 1992-11-05
JPS59139354A (ja) 1984-08-10
SG67087G (en) 1988-02-19

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