RU2160765C2 - Wax-containing liquid composition, depressants based on the latter, and method for lowering flow temperature of wax-containing liquid - Google Patents

Abstract

FIELD: crude oil treatment reagents. SUBSTANCE: invention relates to substances used for lowering flow temperature of wax-containing liquid hydrocarbons. Such depressant is, in particular, prepared by reaction of hydrocarbyl- substituted phenol, in which hydrocarbyl radical contains more than 30 carbon atoms, with C₁-C₁₂-aldehyde or its precursor. More specifically, depressant can be employed for treatment of crude oils with flow temperatures 4 C or higher. EFFECT: improved depressant efficiency. 13 cl, 1 dwg, 16 ex

Description

 This invention relates to substances used to lower the temperature of the loss of fluidity (solidification) of wax-containing liquid hydrocarbons, and their compositions and methods for their preparation.

 Various types of distillate oils, such as diesel fuels, oils of lubricating viscosity, automatic transmission fluids, hydraulic oils, oils for home heating appliances, crude oils and their fractions require depressant additives to lower the temperature of loss fluidity (solidification) in order to enable them to flow freely at lower temperatures. In such oils, kerosene is often included as a solvent for wax, in particular, which is present in distillate oil fuels. However, the need for kerosene used for jet fuel, over the years, makes it necessary to reduce the proportion of kerosene present in distillate oil fuels. This, in turn, requires the addition of wax crystal modifiers to make up for the lack of kerosene. Moreover, the need for depressant additives to lower the pour point of the oil (depressant additives) for crude oils may be even more important since the addition of kerosene is believed to be economically undesirable.

 In Pat. US 5,039,437, Martella et al., August 13, 1991 (and US Pat. No. 5,082,470, Martella et al., January 21, 1992, division thereof) disclose alkyl phenol-formaldehyde condensate additives to improve the flow properties of hydrocarbon oils at low temperature . The polymer composition has a number average molecular weight of at least about 3,000 and a molecular weight distribution of at least about 1.5; in the alkylated phenolic reactant, the alkyl groups are generally linear, have from 6 to 50 carbon atoms and have an average number of carbon atoms from about 12 to 26; and not more than about 10 mol.% of the alkyl groups in the alkylated phenol have less than 12 carbon atoms, and not more than 10 mol.% of the alkyl groups in the alkylated phenol have more than 26 carbon atoms.

In Pat. U.S. 4,565,460; Dorer, Jr., et al., January 14, 1986 (and U.S. Pat. 4,559,155, December 17, 1985, 4,565,550, January 21, 1986, 4,575,526, March 11, 1986, and 4,613,342, September 23, 1986, divisions thereof) disclose additive combinations to improve the cold flow properties of hydrocarbon fuel compositions. The composition includes a depressant supplement, which may be a hydrocarbyl-substituted phenol of the formula (R ^* ) _a -Ar- (OH) _b , where R ^* is a hydrocarbyl group selected from the group consisting of hydrocarbyl groups with from about 8 to about 39 carbon atoms and polymers with at least 30 carbon atoms. Ar is an aromatic moiety which may include linked polynuclear aromatic moieties represented by the general formula ar - (- Lng-ar -) - _w (Q) _mw , where w is an integer from 1 to about 20. Each is a bridging bond of the type including alkylene bonds (e.g., —CH ₂ — among others).

SUMMARY OF THE INVENTION
The present invention provides a method of reducing the pour point of a wax-containing (eg, paraffin-containing) liquid, comprising adding to said liquid a temperature-reducing fluidity loss quantity of a hydrocarbyl-substituted phenol having an average number of carbon atoms in the hydrocarbyl substituent of at least 30 (preferably more than 30 carbon atoms), and an aldehyde from 1 to about 12 carbon atoms, or its source. The invention further encompasses a wax-containing liquid composition comprising a wax-containing liquid, wherein the liquid has a pour point (before processing) of at least 4 ^° C (40 ^° F) and a temperature reducing pour point of the amount of the above depressant to lower the pour point .

 Finally, the present invention includes a method for producing a reaction product of (a) a hydrocarbyl-substituted phenol and (b) an aldehyde with 1-12 carbon atoms. The method is particularly suitable when the hydrocarbyl group contains at least 30 carbon atoms, but can also be applied to the case of shorter groups, for example, alkyl groups with 24-28 carbon atoms.

 Detailed description of the invention.

 A first aspect of the present invention relates to a depressant additive lowering the pour point, comprising the reaction product of (a) a hydrocarbyl-substituted phenol having an average of at least 30 carbon atoms in the hydrocarbyl substituent and (b) an aldehyde of 1-12 , preferably with 1 to 4 carbon atoms, or its source.

 Hydrocarbyl-substituted phenols are known substances, as well as their production method. When the term “phenol” is used here, it must be borne in mind that this term is not believed to limit the aromatic group to phenol (unless the context indicates this, for example, in the examples), although benzene may be the preferred aromatic group . Rather, it should be borne in mind that in the broad sense this term includes hydroxy aromatic compounds in general, for example, substituted phenols, hydroxy naphthalenes, etc. Thus, the phenol aromatic group can be mononuclear or polynuclear, substituted, and can to include other types of aromatic groups as well.

 Thus, the aromatic group of the hydroxyaromatic compound may be the only aromatic ring, such as a benzene ring, a pyridine ring, a thiophene ring, a 1,2,3,4-tetrahydronaphthalene ring, etc., or a polynuclear aromatic moiety. Such polynuclear parts may be of a condensed type; i.e., in which the pairs of aromatic rings that make up the aromatic group are divided at two points, as it is found in naphthalene, anthracene, azanaphthalenes, etc. The polynuclear aromatic moieties can also be of a related type, in which at least two rings (either mono or polynuclear) are connected by bridging bonds to each other. Such bridge bonds may be selected from the group consisting of carbon-carbon bonds between aromatic rings, ether bonds, keto bonds, sulfide bonds, polysulfide bonds with from 2 to 6 sulfur atoms, sulfinyl bonds, sulfonyl bonds, methylene bonds, alkylene bonds , di- (lower alkyl) methylene bonds, lower alkylene ether bonds, alkylene keto bonds, lower alkylene sulfur bonds, lower alkylene polysulfide bonds with from 2 to 6 carbon atoms, amino bonds, polyamino bonds and mixtures of such divalent moieties stick ties. In some cases, more than one bridging link may be present in the aromatic group between the aromatic rings. For example, a fluorene ring has two benzene rings joined by both a methylene bond and a covalent bond. It is believed that such a ring has 3 cores, but only two of them are aromatic. Typically, an aromatic group should contain only carbon atoms in the aromatic rings per se, although other non-aromatic substitution, such as, in particular, substitution in short chain alkyl, may also be present. Thus, for example, methyl, ethyl, propyl and t-butyl groups may be present in aromatic groups, even if such groups are not represented in detail in the structures considered here.

и т.д., где M есть метил, Et есть этил или этилен, как целесообразно, и Pr - н-пропил.Specific examples of single ring aromatic parts are as follows:

etc., where M is methyl, Et is ethyl or ethylene, as appropriate, and Pr is n-propyl.

и т.д.Specific examples of condensed ring aromatic parts are:

etc.

и т.д.), низший алкилен сульфидных связей (например, где один или более -O-'ы в низший алкилен эфирных связях замещен на атом S), низший алкилен полисульфидных связей (например, где один или более -О- замещен на -S-_2-6 группу), амино связей (например,

-CH₂N-, -CH₂NCH₂-, -алк-N-,
где алк - низший алкилен, и т. д.), полиамино связей (например, -N(алкN)_1-10, где незаполненные свободные N валентности заняты H или R^O группами), связей, получаемых из оксо- или кето-карбоновых кислот (например)

где каждый из R¹, R² и R³ есть независимо гидрокарбил, предпочтительно алкил или алкенил, наиболее предпочтительно низший алкил, или Н, R⁶ есть Н или алкильная группа и х - целое число от 0 до около 8, и смесей таких мостиковых связей (причем каждый R^O является низшей алкильной группой). Конкретными примерами связанных частей являются:

Обычно все из этих ароматических групп не имеют заместителей, за исключением особо названных. По таким соображениям, как стоимость, доступность, рабочая характеристика и т.д., ароматической группой обычно является бензольное ядро, бензольное ядро с низшим алкиленовым мостиком или нафталиновое ядро. Наиболее предпочтительной ароматической группой является единичное бензольное ядро.In the case where the aromatic part is a linked polynuclear aromatic part, it can be represented by the general formula
ar (-L-ar-) _w ,
where w is an integer from 1 to about 20, each ar is a separate ring or a condensed ring aromatic nucleus with from 4 to about 12 carbon atoms and each is independently selected from the group consisting of carbon-carbon single bonds between ar nuclei, ether bonds ( e.g. -O-), keto bonds (e.g. -C (= O) -), sulfide bonds (e.g. -S-), polysulfide bonds with 2 to 6 sulfur atoms (e.g. -S- _2-6 ) sulfonyl bonds (e.g. -S (O) -), sulfonyl bonds (e.g. -S (O) ₂ -), lower alkylene bonds (e.g. -CH ₂ -, -CH ₂ -CH ₂ -, -CH ₂ -CHR ^O -), mono (lower alkyl) -methylene bonds (e.g., -CHR ^O -), di (lower alkyl) -methylene bonds (e.g. -CR ^O ₂ -), lower alkylene ether bonds (e.g. -CH ₂ O-, -CH ₂ O-CH ₂ -, -CH ₂ -CH ₂ O-, -CH ₂ CH ₂ OCH ₂ CH- ₂ , -CH ₂ CHOCH ₂ CH-, -CHR ^O -O-, -CHR ^O - ^O -CHR ^O -,

etc.), lower alkylene sulfide bonds (for example, where one or more —O— in lower alkylene ether bonds is substituted with an S atom), lower alkylene polysulfide bonds (for example, where one or more —O— is substituted on -S- _2-6 group), amino bonds (e.g.

-CH ₂ N-, -CH ₂ NCH ₂ -, -alk-N-,
where alk is lower alkylene, etc.), polyamino bonds (for example, -N (alkN) _1-10 , where unfilled free N valencies are occupied by H or R ^O groups), bonds derived from oxo- or keto-carboxylic acids (for example)

where each of R ¹ , R ² and R ³ is independently hydrocarbyl, preferably alkyl or alkenyl, most preferably lower alkyl, or H, R ⁶ is H or an alkyl group and x is an integer from 0 to about 8, and mixtures of such bridging bonds (with each R ^O being a lower alkyl group). Specific examples of related parts are:

Typically, all of these aromatic groups have no substituents, with the exception of those specifically mentioned. For reasons such as cost, availability, performance, etc., the aromatic group is usually a benzene core, a benzene core with a lower alkylene bridge, or a naphthalene core. The most preferred aromatic group is a single benzene core.

 This first reactant is a hydroxyaromatic compound, i.e., a compound in which at least one hydroxy group is directly attached to an aromatic ring. The number of hydroxy groups per aromatic group can vary from 1 up to the maximum number of such groups that can be located on the hydrocarbyl-substituted aromatic part, while still maintaining at least one, and preferably at least two, positions at least some of which are preferably adjacent (ortho) to the hydroxy group, which are suitable for further interaction by condensation with aldehydes (described in detail below). Thus, most reactant molecules must have at least two unsubstituted positions. Suitable substances include hydrocarbyl-substituted catechols, resorcinols, hydroquinones and even pyrogallols and phloroglucins. However, it is most preferred that each aromatic ring carries one hydroxyl group and, in the preferred case, when hydrocarbyl substituted phenol is used, the substance should contain one benzene core and one hydroxyl group. Of course, a small fraction of the molecules of the aromatic reactant may not contain hydroxyl substituents. For example, a small amount of a hydroxy-free substance may be present as an impurity. However, this does not invalidate the essence of the present invention, since the starting material is functional and usually contains at least one hydroxyl group per molecule.

Similarly, a hydroxyaromatic reactant is characterized in that it is hydrocarbyl substituted. The term "hydrocarbyl substituent" or "hydrocarbyl group" is used here in its usual sense, which is well known to specialists in this field. In particular, it refers to a group having a carbon atom directly bonded to the remainder of the molecule and having a predominantly hydrocarbon character. Examples of hydrocarbyl groups include:
(1) hydrocarbon substituents, i.e., aliphatic (e.g., alkyl or alkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents and aromatic, aliphatic and alicyclic substituted aromatic substituents, as well as cyclic substituents in which the ring ends with another part of the molecule (for example, two substituents together form an alicyclic radical);
(2) substituted hydrocarbon substituents, i.e., substituents containing non-hydrocarbon groups which, in the context of the present invention, do not predominantly alter the hydrocarbon substituent (e.g., halogen (especially chlorine and fluorine), hydroxy, alkoxy, mercapto, alkyl mercapto nitro, nitroso and sulfoxy);
(3) hetero substituents, i.e., substituents which, although they are primarily of a hydrocarbon nature, in the context of the present invention, contain a different atom than carbon in a ring or chain, otherwise consisting of carbon atoms. Hetero atoms include sulfur, oxygen, nitrogen, and are substituted with pyridyl, furyl, thienyl, and imidazolyl. In general, no more than two, preferably not more than one, non-hydrocarbon substituents may be present for every ten carbon atoms in the hydrocarbyl group; usually, non-carbon substituents should not be present in the hydrocarbyl group.

 Preferably, the hydrocarbyl group is an alkyl group. Typically, an alkyl group may contain at least 30 carbon atoms, or if the alkyl group is a mixture of alkyl groups, the mixture may contain an average of at least 30 carbon atoms, usually from 31 to 400 carbon atoms, preferably from 31 up to 60, and more preferably from 32 to 50 or 45 carbon atoms. In a preferred embodiment, the alkyl group in the composition may be a mixture of alkyl groups, which may vary in length from one single molecule to another. While the fraction of molecules may contain an alkyl group of less than 30 carbon atoms, the composition as a whole is usually characterized as having an alkyl substitution of at least 30 carbon atoms in length. However, for some embodiments of the present invention, the alkyl group may be shorter containing less than 30 carbon atoms, for example, preferably from 24 to 28 carbon atoms. Alkyl groups, in any case, can be obtained from either linear or branched olefin reactants; sometimes linear are preferred, although longer chain substances tend to have higher branching ratios. It is likely that some branching is also introduced using the rearrangement mechanism during the alkylation process.

In a preferred embodiment, the hydrocarbyl groups used include a mixture of alkyls predominantly 30 to 36 carbon atoms in length, having a number average carbon number of about 34.4 and a weight average carbon number of about 35.4. This substance is characterized as having approximately the following distribution along the chain length:
C ₂₆ - 0.3%
C ₂₈ - 11.9
C ₃₀ - 16.7
C ₃₂ - 11.3
C ₃₄ - 8.6
C ₃₆ - 6.6
C ₃₈ - 5.0
C ₄₀ - 3.8
C ₄₂ - 2.9
C ₄₄ - 2,3
C ₄₆ - 1.8
C ₄₈ - 1.5
C ₅₀ - 1.4
C ₅₂ - 1.3
Thus, the hydrocarbyl substituent contains a number average of more than 30 carbon atoms. Such substituents are preferably alkyl groups in which the number average number of carbon atoms in the alkyl chain is 31-40, more preferably 32-38.

A hydrocarbyl group can be obtained from the corresponding olefin; for example, a C ₂₆ alkyl group is derived from a C ₂₆ alkene, preferably 1-alkene, a C ₃₄ alkyl group is derived from a C ₃₄ alkene, and lengthwise mixed groups are obtained from the corresponding olefin mixture. When a hydrocarbyl group is a hydrocarbyl group having at least about 30 carbon atoms, it is often an aliphatic group (or a mixture of such groups) derived from homo- or interpolymers (e.g. copolymers, terpolymers) of mono- and di-olefins having from 2 to 10 carbon atoms, such as ethylene, propylene, butene-1, isobutene, butadiene, isoprene, 1-hexene, 1-octene, etc. For suitable use as a depressant additive (reducing the temperature loss of fluidity ) at least part of alkyl g the group or group is preferably a straight chain, i.e. mostly linear. It is believed that this feature is preferred in order to provide this chain with a more favorable interaction with the chain structure of wax-forming hydrocarbons. It is known that in many cases there should be a methyl branch at the point of attachment of the alkyl chain to the aromatic ring, even when an α-olefin is used. It is believed that this is within the scope of the meaning of unbranched chain or linear alkyl groups. Similarly, in some cases, the fraction of the alkyl groups may contain a lower alkyl branch at the attachment point (or α position), possibly due to the migration of the active site during the alkylation reaction. Commonly used olefins are 1-mono olefins, such as ethylene homopolymers. These aliphatic hydrocarbyl groups can also be obtained from halogenated (e.g., chlorinated or brominated) analogues of such homo- or interpolymers. Such groups, however, can be obtained from other sources, such as monomeric high molecular weight alkenes (for example, 1-tetracontain) and their chlorinated analogues and hydrochlorinated analogues, aliphatic oil fractions, in particular paraffin waxes and cracked and chlorinated analogues and their hydrochlorinated analogues, petroleum jelly oils, synthetic alkenes, such as alkenes obtained by the Ziegler-Natta method (for example, poly (ethylene) greases) and other sources known to those skilled in the art. Any unsaturation in hydrocarbyl groups can be reduced or eliminated by hydrogenation according to methods known in the art. Obtaining by means of or by the use of substances that are substantially free of chlorine or other halogens, is sometimes preferable for environmental reasons.

 In one embodiment, a portion of the hydrocarbyl groups is derived from polybutene. In another embodiment, a portion of the hydrocarbyl groups is derived from polypropylene. In a preferred embodiment, the hydrocarbyl group is prepared from a mixture of substantially unbranched olefins having chain lengths predominantly of 30-36 carbon atoms, as described above.

 More than one such hydrocarbyl group may be present on each aromatic nucleus in an aromatic group, but usually no more than 2 or 3. Most often, only 1 hydrocarbyl group is present on the aromatic part, in particular when the hydrocarbyl-substituted phenol is based on a single benzene ring .

 The attachment of a hydrocarbyl group to the aromatic moiety of the first reactant of the present invention can be accomplished using a number of techniques well known to those skilled in the art. In particular, one suitable technique is the Friedel-Crafts reaction, in which an olefin (for example, a polymer containing an olefin bond), or a halogenated or hydrohalogenated analog thereof, is reacted with a phenol in the presence of an Lewis acid catalyst. Methods and conditions for carrying out such reactions are well known to specialists in this field. See, for example, a discussion in an article entitled “Alkylation of Phenols” in “Kirk-Othmer Encyclopedia of Chemical Technology”, Third Edition, Vol. 2, pages 65-66, Interscience Publishers, a division of Wiley and Company, N.Y. Other equally relevant and convenient methods for attaching a hydrocarbon-based group to an aromatic moiety can easily come to mind by those skilled in the art.

Example 1
12-liter, four-, round-bottomed flask equipped with a thermocouple, a nitrogen purge tube (14 l / hr (0.5 std. Ft ³ / hr (std.ft ³ / hr) N _2), a mechanical stirrer, Deam-Stark trap Friedrich's refrigerator is charged with 1902 g (20.2 equivalents) of distilled (95%) phenol. The phenol is heated with stirring to 100 ^° C. and 62.4 g of Amberlyst 15 ^TM catalyst (supplied by Rohm and Haas) are charged. The mixture is then heated to 150 ^o C and incubated for 1.5 hours, collecting 9.5 ml of colorless condensate in a trap.The mixture is maintained at 150 ^o C, while 2150 g of a mixture of C ₃₀₊ α-olefins from Chevron charged over 1.3-hour period, after which the mixture was kept at 150 ^o C for a further 5 hours, the mixture was cooled to 120 ^o C and filtered through a glass microfiber filter pad to remove the catalyst The filtrate is distilled at 160 ^o C.. at a pressure of 1.5 kPa (kPa) (11 mm H _g .) The resulting material was again filtered through a microfiber glass filter pad at 120 ^° C. to give the product as a liquid, which solidified as a waxy solid.

Example 2
In the apparatus described in example 1, load 2140 g (22.8 equivalents) of distilled phenol. Purge with nitrogen at 31 L / hr (1.1 stand.fut ³ / h (std. Ft ³ / hr). After heating to 100 ^o C, charged with 61.4 g of Amberlyst ^TM 15 catalyst and 14 ml colorless collected condensate. A mixture of maintained at 150 ^° C., while 2240 g of Cheron’s _24-28 α-olefins were charged over a 1.5 hour period, after which the mixture was kept at 150 ^° C. for another 3 hours, the mixture was cooled to 120 ^° C and filtered through a glass microfibrillar filter pad to remove the catalyst. The filtrate is distilled at 150 ^o C under a pressure of 2.4 kPa (kPa) (18 mm H _g) for 0.5 hours. The resulting vesche GUT microfibrillar again filtered through a glass filter pad at 110 ^o C, to give the product as a pale yellow oil which solidified as a white wax.

 The second component, which interacts with the formation of a depressant additive, is an aldehyde with from 1 to 12 carbon atoms, or its source. Suitable aldehydes have the general formula RS (O) H, where R is preferably hydrogen or a hydrocarbyl group described above, although R may include other functional groups that do not interfere with the condensation reaction (described below) of the aldehyde with a hydroxyaromatic compound. This aldehyde preferably contains from 1 to 12 carbon atoms, more preferably from 1 to 4 carbon atoms and even more preferably from 1 to 2 carbon atoms. Such aldehydes include formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, pentanaldehyde, caproaldehyde, benzaldehyde and higher aldehydes. Monoaldehydes are preferred. The most preferred aldehyde is formaldehyde, which can be introduced in the form of a solution, but which is more often used in polymer form, in the form of paraformaldehyde. Paraformaldehyde can be considered a reactive equivalent or an aldehyde source. Other reactive equivalents include hydrates or cyclic trimers of aldehydes.

 Hydrocarbyl phenol and aldehyde are usually reacted in relative amounts within the molar ratios of phenol: aldehyde 2: 1 to 1: 1.5. Preferably, approximately equal molar amounts up to 30% molar excess of aldehyde (based on monomeric aldehyde) should be used. Preferably, the amount of aldehyde exceeds the amount of hydrocarbyl phenol by 5-20, more preferably by 8-15 percent, calculated as a molar percentage. The components are reacted under conditions leading to the formation of an oligomer or polymer. The molecular weight of the product may depend on parameters such as equivalent reactant ratios, reaction temperature and time, and the presence of impurities. The product may have from 2 to 100 aromatic units (i.e., substituted aromatic phenolic monomer units) present ("repeating") in its chain, preferably from 3 to 70 such units, more preferably from 4 to 50, 30 or 14 links. When the hydrocarbyl phenol, in particular, is an alkyl phenol having 24-28 carbon atoms in the alkyl chain, and when the aldehyde is formaldehyde, the substance will preferably have a number average molecular weight of from 1,000 to 24,000, more preferably from 2,000 to 18,000, still more preferably from 3,000 to 6,000. The molecular weights of hydrocarbyl substituent substances with a chain length of about 34 carbon atoms should be proportionally relatively higher.

The hydrocarbyl phenol and the aldehyde are reacted by mixing the alkyl phenol and the aldehyde in an appropriate amount of an oil solvent or, optionally, another solvent, such as an aromatic solvent, such as sulfuric acid, sulfonic acid, such as alkyl phenyl sulfonic acid, para-toluenesulfonic acid or methanesulfonic acid, organic acid such as glyoxylic acid or Amberlyst ^TM catalyst solid, microporous catalyst - slightly cross-linked sulfonated polystyrene-divinylbenzene resins supplied by Rohm and Haas. The mixture is heated, usually to 90-16 ^° C, preferably from 100 to 150 ^° C or to 120 ^° C, for a suitable period of time, such as from 30 minutes to 6 hours, preferably 1-4 hours, to remove the water generated during condensation. Time and temperature correlate, since a reaction at a lower temperature usually requires a longer time, etc. The selection of optimal conditions is within the qualifications of a specialist in this field. If necessary, the reaction mixture can then be heated to a higher temperature, for example, 140-180 ^o C, preferably 145-155 ^o C, to remove volatile products and to shift the reaction towards its completion. The product can be treated with a base such as NaOH, if necessary, in order to neutralize the strong acid catalyst and obtain the sodium salt of the product, if necessary, and then the product is isolated using conventional techniques, such as filtration.

и позиционные изомеры их.The product of this reaction can usually be considered as including polymers or oligomers having the following repeating structure:

and positional isomers of them.

Получение депрессантных присадок по вышеуказанному способу обеспечивает вещество, которое обычно демонстрирует улучшенные свойства, связанные с их манипулированием, такие как повышенная температура вспышки, по сравнению с депрессантными присадками, получаемыми при помощи способов предшествующего уровня техники.However, a portion of the formaldehyde that is preferably used is believed to be incorporated into the molecular structure as substituent groups and linking groups, such as groups illustrated by the following types, including ether bonds and hydroxymethyl groups;

The preparation of depressant additives according to the above method provides a substance that usually exhibits improved properties associated with their manipulation, such as an increased flash point, compared with depressant additives obtained using the methods of the prior art.

Example 3
A 5-liter vessel with a set of equipment similar to Example 1 was charged with 1850 g of C ⁺ ₃₀ alkyl phenol from Example 1. The substance was heated with stirring to 100 ^° C and 11.2 g of concentrated sulfuric acid was added over a period of 10 minutes, and then immediately 9.6 g of paraformaldehyde (91%) are charged. Eleven additional downloads of paraformaldehyde were carried out over the next 3 hours, a total of 115 g, and condensate was collected in a trap during this time period. After a 3-hour period, add a drop of anti-foaming agent, and the temperature is raised to 115 ^o C for 0.5 hours, kept at this temperature for 2 hours, and then heated to 150 ^o C for 0.3 hours and maintained at this temperature for 2.0 hours. 631 g of a commercial paraffin high boiling solvent are added, lowering the temperature to 131 ^° C. To this mixture is added 18.4 g of 50% (by weight) aqueous sodium hydroxide over a period of 10 minutes. The mixture was heated to 150 ^° C. for 0.5 hours and another 992 g of paraffin solvent was added, as well as 95 g of filter aid. After 1 hour at this temperature, the mixture was filtered at 75 ^° C using an additional filter aid and the filter aid was washed with an additional 292 g of paraffin solvent. The product is a filtrate that contains approximately 50% of a high boiling paraffin solvent.

Example 4
A 1 liter, four-necked, round-bottomed flask equipped with a nitrogen purge line, stirrer, thermocouple pocket, Dean-stark collection trap, Friedrich's refrigerator, charged 360.2 g (0.787 equivalents) of predominantly C _24-28 alkyl substituted phenol. The batch was heated with stirring under nitrogen duct 14 liters / hour (0.5 stand.fut ³ / h (std. Ft ³ / hr), to 70 ^o C, and add 75 g of the crude aromatic solvent-solvent (initial boiling temperature of 179 ^o C). The mixture is heated to 100 ^o C and over a 2.8-hour period, 28.89 g of paraformaldehyde (91%; 0.875 equivalents) are added in 12 equal portions. After adding the first portion, 2.06 g of concentrated sulfuric acid are added acid, as well as a drop of kerosene solution of a silicone antifoam agent (Dow Corning ^TM 200 Fluid). After complete addition, araformaldegida, the mixture is heated to 115 ^o C over 0.25 hours and maintained at this temperature for 1.7 hours, then heated to 150 ^o C over 0.4 hours and held at this temperature for 1.5 hours and then heated to 156 ^° C. for about 0.5 hours. Adding 295 g of an additional diluent aromatic solvent causes the temperature to drop to 122 ^° C. Sodium hydroxide, 3.8 g of a 50% solution and 19.7 g are added. filter aid (FAX-5 ^TM ). The mixture is again heated to 150 ^° C. After 0.8 hours at 150 ^° C., the mixture is cooled to less than 50 ^° C. and filtered to obtain 728.2 g of a brown oily filtrate, which is a product containing approximately 50% solvent.

Example 5
Basically, the procedure of Example 4 is repeated, except that a 5 liter vessel is used. The vessel was charged with 1870 g of condensate C _24-28 -alkylphenol / formaldehyde and 389 g of o-xylene. Concentrated sulfuric acid, 11.3 g, was added at 80 ^° C. over a 10 minute period. Paraformaldehyde, 150 g, 91%, is loaded in 12 portions at 80-100 ^o C for 3 hours, and the water formed during condensation is collected. Two drops of antifoaming agent are added and the mixture is heated to 115 ^° C. for 2 hours, then to 150 ^° C. for 1 hour and kept at this temperature for another 2 hours. Then add 642 g of technical paraffin high boiling solvent, lowering the temperature to 131 ^o C. To the mixture add 17.9 g of 50% (by weight) aqueous sodium hydroxide dropwise over a 1-minute period. The mixture is heated to 150 ^° C. for 0.5 hours, then adjusted to 130 ^° C. at 8.6 kPa (kPa) (65 mm H _g ) for 1 hour. A further 1283 g of high-boiling technical paraffin solvent are added, as well as 95 g of filter aid. After additional stirring for 1 hour, the mixture is filtered through 25 g of filter aid at 110 ^o C.

Example 6
A 1-liter, four-necked, round-bottom flask equipped as in Example 4 was charged with 360 g of C _24-28 -alkylphenol and heated with stirring and with a nitrogen purge (17-28 L / hr (0.6-1.0 standard feet) ³ / hr (std. Ft ³ / hr) to 83 ^° C. Sulfuric acid, 2.2 g was added, and the mixture was heated to 101 ^° C. Paraformaldehyde, 29.11 g (91%), was added in 16 portions, over a three hour period, and condensate is collected.

The mixture is heated to 115 ^o C for 0.4 hours and incubated for 1.75 hours, then heated to 150 ^o C for 0.4 hours and incubated for 1.75 hours. The mixture was allowed to cool to 125 ^° C. and 4.09 g of 50% sodium hydroxide was added. The mixture is heated and maintained at 150 ^° C. for 1 hour. Then add 371 g of industrial paraffin high boiling solvent, as well as 22 g of filter aid. The mixture was cooled to some extent and filtered using an additional filter aid over a 3-hour period. The filtrate is a product.

Example 7
In 760 liter reaction vessel with a glass jacket, equipped with a stirrer, column, condenser, receiver (distillate), and purging with nitrogen (570 l / h (20 std. Ft ³ / hr (std. Ft ³ / hr) is charged with 155 kg C _24-28 -alkylphenol and 31 kg of a technical aromatic solvent solvent. The mixture is heated, with stirring, to 79-85 ^o C, after which 890 g of concentrated sulfuric acid is added. The mixture is heated to 104-110 ^o C and added 12.2 kg of paraformaldehyde (91%), in 9 equal portions, over 5-6 hours, removing the aqueous distillate as it forms. The mixture is heated to 118-124 ^o C for three hours and maintained at this temperature for another 2 hours, then to 127 ^o C, while adding 1.35 kg of 50% aqueous sodium hydroxide.The mixture is heated to 149-154 ^o C for two hours (with increased flow of nitrogen) to remove residual water.The mixture is cooled to 60 ^o C, and add 126 kg of additional technical aromatic solvent solvent to obtain a 50% solvent. The mixture is filtered at 60-66 ^° C. using 2.7 kg of filter aid.

Example 8
The procedure of Example 7 is mainly repeated, using a molar equivalent amount of C ₃₀₊ alkylphenol instead of C _24-28 alkylphenol. In this example, no solvent is used at the initial stage of the reaction, but the amount added after the reaction is the calculated amount needed to obtain 50% polymer, 50% solvent. In an alternative embodiment of this example, a solvent is used, as in Example 7.

The depressant additives of the present invention, which have an average alkyl chain length of at least 30 carbon atoms, are particularly suitable for lowering the pour point of certain petroleum oils, i.e., crude oils or fractions of crude oils, such as residual oil, vacuum gas oil or vacuum residual oils (Bunker C crude oil), i.e. naturally occurring and partially refined oils, including partially refined oils derived from oil. Suitable oils are typically oils that have an initial (i.e., unmodified, or prior to treatment with a depressant additive) pour point of at least 4 ^° C (40 ^° F), preferably at least 10 ^° C (50 ^o F) or more preferably 16 ^o C (60 ^o F), although they also show some advantage in certain oils that go beyond these limits. The use of these substances, in particular, is valuable for those crude oils that are difficult to process in other ways. For example, they are particularly useful for oils (crude oils or fractions of crude oils, such as those described above) that have a wax content higher than 5%, preferably higher than 10%, by weight, measured using UOP-46 -85 (UOP method, "Paraffin wax content of petroleum oils and asphalts"). (Wax-containing substances are sometimes referred to as paraffin-containing substances, with paraffin being the approximate equivalent of wax, and in particular oil waxes. The present invention, in particular, is not limited to any particular type of wax, which may cause a loss of fluidity in a given liquid. Thus It covers paraffin wax, microcrystalline waxes and other waxes. It is known that for many important materials, such as petroleum oils, the content of paraffin wax is especially important). Substances of depressant additives are also useful for oils with a high content of high boiling fraction, i.e., in which a fraction boiling between 271 ^° C (520 ^° F) and 538 ^° C (1000 ^° F) (i.e., about C ₁₅ and above) is at least 25%, preferably at least 30%, more preferably at least 35%, of an oil (excluding any fraction of 7 or less carbon atoms). Among high boiling oils, they are especially useful if more than 10%, preferably more than 20%, more preferably higher than 30%, of the high boiling (271-538 ^o C) fraction boils between 399 ^o C (750 ^o F) and 538 ^o C (1000 ^° F) (i.e., about C ₂₅ and higher) as determined by ASTM D 5307-92. Preferably, this highest boiling point (399-538 ^° C.) should include at least 10% of the total oil content (excluding any fraction of 7 or less carbon atoms). Preferably, the analysis is carried out on crude oil from a stock tank crude, which is degassed and which contains little or no C ₄ fraction or lower. They are also useful for materials that have an AP1 density higher than 20 ^° (ASTM D-287-82).

где B_n представляет весовой процент фракции масла кипящей нефти, содержащей алкан C_nH_2n+2 и n - число углеродов соответствующего парафина. Значения этих кипящих фракций определяют по ASTM способу D 5307-92. Наиболее предпочтительно, когда подходящие масла будут иметь определенное выше значение N_W, а также одну или более из выше определенных характеристик, таких как температура потери текучести выше 4^oC и/или содержание воска выше чем 5% (UOP-41-85 способ).These depressant additives are, in many cases, useful for the treatment of oils (e.g., crude oils and their fractions) that have N _w higher than 18, preferably higher than 20, and more preferably higher than 22. Here N _W is the weight average carbon atoms of oil molecules, determined using

where B _n represents the weight percent of the boiling oil fraction containing alkane C _n H _{2n + 2} and n is the carbon number of the corresponding paraffin. The values of these boiling fractions are determined according to ASTM method D 5307-92. Most preferably, suitable oils will have the N _W value as defined above, as well as one or more of the above defined characteristics, such as pour point above 4 ^° C and / or wax content higher than 5% (UOP-41-85 method) .

The amount of depressant additive used in the oil or other wax-containing liquid should correspond to an amount suitable to lower its pour point by a measurable value, i.e., at least 0.6 ^o C (1 ^o F), preferably at least 2 ^° C. (3 or 4 ^° F.), and even more preferably 6 ^° C. (10 ^° F.). This decrease in pour point can be easily determined by those skilled in the art using the ASTM D-97 methodology. Typically, the amount of depressant used should be from 50 to 10,000 ppm by weight (ppm), preferably from 100 to 5,000 ppm, more preferably from 200 to 2,000 ppm, based on the liquid to which it is added.

Examples 9-16
The depressant additive obtained as in Example 13 is introduced in the amounts indicated for the various crude oils listed in the table at the end of the description, each of which has a pour point of at least 4 ^° C before treatment. The depressant additive is added in the usual way, t that is, when mixing in crude oil at a temperature above the temperature of the loss of fluidity of the oil, although other methods of addition may be obvious to a person skilled in the art. The pour point decreases as indicated.

The drawing shows the composition Anadarco Tucker crude oil, a similar composition of examples 11 and 14, presented as% Weight as a function of the boiling fraction. The large peak for C ₄₀ in both cases represents the sum of the components boiling in the C ₄₀ range and above.

 The depressant additives of the present invention can be administered in pure form (solvent content 0%) or in the form of concentrates containing a solvent such as hydrocarbon oil. When administered as a concentrate, the amount of oil can be up to 90% of the composition, usually 10-90%, preferably 30-70%, and more preferably 40-60%. Alternatively, depressant additives can be administered as dispersions in substances such as acetates (for example, 2-ethoxyethyl acetate) or aqueous glycol mixtures (for example, a mixture of ethylene glycol and water).

 Each of the documents referenced above is incorporated herein by reference. In addition, in the examples, or unless otherwise indicated, all numerical quantities in this description, defining quantities of substances, reaction conditions, molecular weights, number of carbon atoms, etc., should be considered as modified by the word "about". Unless otherwise specified, each chemical or composition referred to herein shall be interpreted as a technical grade substance that may contain isomers, by-products, derivatives, and other such substances that are believed to be commonly present in technical grades. However, the amount of each chemical component is presented excluding any diluent or diluent oil that may normally be present in the technical substance, unless otherwise specified. Used here, the expression "containing, mainly" allows you to exclude substances that do not materially affect the basic and new characteristics of the composition to be considered.

Claims (13)

1. A liquid composition containing wax, which includes I) a liquid containing wax with an initial pour point of at least 4 ^° C, and II) a depressant additive comprising the product of reaction (a) of a hydrocarbyl-substituted phenol with an average number of carbon atoms in a hydrocarbyl substituent of at least 30 and (c) an aldehyde with from 1 to 12 carbon atoms or its source, in an amount sufficient to lower the pour point of said wax-containing fluid.  2. The composition according to claim 1, in which the hydrocarbyl-substituted phenol is monohydroxybenzene substituted by an alkyl group with an average number of carbon atoms of at least 30.  3. The composition according to claim 2, in which the alkyl group is a failure mixture of alkyl substituents with the number of carbon atoms, preferably from 30 to 36.  4. The composition according to p. 2, in which the average number of carbon atoms in the alkyl substituents is 31 to 40.  5. The composition according to claim 1, in which the aldehyde is formaldehyde or its source.  6. The composition according to p. 1, in which the reaction product is a reaction product of hydrocarbylphenol and an aldehyde or its source in a molar ratio of from 2: 1 to 1: 1.5 and in which the reaction product comprises from 2 to 100 aromatic units.  7. The composition according to claim 1, in which the liquid containing wax is an oil with a wax content of more than 5%. 8. The composition according to claim 1, in which the liquid containing wax, is an oil in which the fraction with a boiling point between 271 and 538 ^o C includes at least 25% of the oil, except for the fraction with 7 or less carbon atoms.  9. The composition according to claim 1, in which the liquid containing wax is an oil with an average number of carbon atoms greater than 18, with the exception of the fraction with 7 or less carbon atoms.  10. The composition according to claim 1, in which the amount of depressant additives is from 50 to 10,000 parts per million by weight based on the liquid containing wax. 11. A method of lowering the pour point of a liquid containing wax with an initial pour point of at least 4 ^° C., comprising adding a depressant to the liquid, including the product of reaction (a) of a hydrocarbyl-substituted phenol with an average number of carbon atoms in the hydrocarbyl-substituent, at least 30, and (c) an aldehyde with from 1 to 12 carbon atoms or its source in an amount sufficient to lower the pour point of said fluid.  12. The method according to p. 11, in which the depressant additive is added to the liquid containing wax, with stirring at a temperature above the temperature of the loss of fluidity of the liquid containing wax. 13. The use of a depressant additive comprising the reaction product of (a) a hydroxyl substituted phenol with an average number of carbon atoms in the hydrocarbyl substituent of at least 30, and (c) an aldehyde with 1 to 12 carbon atoms or a source thereof to lower the temperature of fluidity loss of a liquid containing wax with an initial pour point of at least 4 ^° C. Priority on points:
September 8, 1995 according to claims 1 to 13;
04/08/1996 according to claims 1 to 13 (clarification of signs).

Images