EP0549918B1 - Demulsifier based on an alkoxylate and process for the preparation of the alkoxylate - Google Patents

Description

The present invention relates to petroleum emulsion breakers containing an alkoxylate of an alkylphenol-formaldehyde resin, an alcohol, a bisphenol or an amine and a process for the preparation of the alkoxylates using a special catalyst.

With the extraction of crude oils, the increasing exploitation of the deposits means that an increasing proportion of water is also extracted. Surface-active substances contained in the crude oils emulsify most of the water, forming stable water-in-oil emulsions. The emulsified water can make up 0.1 to over 50% by weight of the total emulsion. Salts can be dissolved in the emulsion water, which lead to corrosion problems when the crude oil is further processed in the refinery. The emulsion water must therefore be separated before transport or reduced to an acceptable concentration. This is usually done by adding so-called petroleum emulsion splitters, whereby heating the crude oil facilitates and accelerates the separation.

The crude oils differ greatly in their composition depending on their provenance. The natural emulsifiers contained in the crude oils also have a complicated chemical structure, so that in order to overcome their effect, oil demulsifiers (demulsifiers) have to be selectively developed. By opening up new crude oil fields and changing production conditions for older fields, new demulsifiers are constantly needed, which cause faster separation into water and oil and the lowest possible residual water and residual salt quantities.

The most frequently used demulsifiers are ethylene oxide / propylene oxide block copolymers, alkoxylated alkylphenyl-formaldehyde resins, as are described, for example, in DE-PS 27 19 978, alkoxylated polyamines (see, for example, US 3 907 701 and DE-OS 24 35 713) and Crosslinking products of the above basic classes with multifunctional reagents, such as diisocyanates, dicarboxylic acids, bisglycidyl ethers, di- and trimethylolphenols.

However, the known petroleum emulsion splitters often do not quite meet the requirements, since the separation of the emulsion into specification-compliant oil and water with the lowest possible residual oil content either takes too long a time or requires excessive dosages of the splitter.

The object of the present invention was therefore to provide petroleum emulsion splitters which allow the emulsion to be separated as rapidly as possible into oil and water in the shortest possible time, i.e. which show good effectiveness even in low doses.

Since the exploitation of the crude oil fields as far as possible and the complete separation of the residual oil from the water are becoming increasingly important for economic and ecological reasons, the solution to this task is of additional importance.

in der A für einen Ethylen-, Propylen- und/oder Butylen-Rest steht und n = 3-100 ist und in der R für den Rest

• eines Alkylphenol-Formaldehyd-Harzes der Formel II
  
  worin R¹ ein verzweigtkettiger C₃-C₁₈-Alkylrest und y = 3 bis 30 ist;
• eines Alkohols der Formel III
  
  worin R entweder ein C₁-C₂₀-Alkylrest mit x = 1 und z = 0 ist, oder R ein C₂-C₁₀-Alkylenrest mit x = 2 und z = 0 oder mit x = 1, z = 1 und R³ = C₁-C₆-Alkyl- oder C₁-C₂₀-Acylrest ist, oder R ein C₆-C₁₀-Arylrest ist, der mit bis zu 2 C₃-C₁₈-Alkylresten substituiert sein kann, wobei x = 1 und z = 0 ist;
• eines Amins der Formel IV
  
          R⁴-NH₂     IV
  
  worin R⁴ ein linearer oder verzweigter C₁-C₆-Alkyl- oder C₁-C₁₀-Hydroxyalkyl-Rest ist oder einem Rest der folgenden Formel V entspricht
  
  mit R⁵ = H oder C₁-C₃-Alkyl, m = 2 bis 4, r = 2 bis 10 und q = 0 bis 5,
• eines Bisphenols der Formel VI
  
  worin k = 0 bis 3 sowie R⁶ und R⁷ unabhängig voneinander H und C₁-C₃-Alkyl sein kann; oder
• eines Polyethylenimins mit dem Molekulargewicht M_w von 2000 bis 50 000

steht; wobei die

Reste jeweils anstelle der am Sauerstoff oder Stickstoff stehenden Wasserstoffe der Alkylphenol-Formaldehyd-Harze, der Alkohole, Bisphenole, Amine oder Polyethylenimine stehen und p der Anzahl der zu alkoxilierenden Wasserstoffe entspricht, dadurch gekennzeichnet, daß das Alkoxilat der Formel I eine Polydispersität Q = $\overline{\text{M}}$

_w/ $\overline{\text{M}}$

_n von mindestens 1,7 aufweist.It has now been found that this object can be achieved using petroleum emulsion splitters based on an alkoxylate of the general formula I

in which A represents an ethylene, propylene and / or butylene radical and n = 3-100 and in R represents the rest

• an alkylphenol-formaldehyde resin of the formula II
  
  wherein R¹ is a branched chain C₃-C₁₈ alkyl group and y = 3 to 30;
• an alcohol of formula III
  
  wherein R is either a C₁-C₂₀ alkyl group with x = 1 and z = 0, or R is a C₂-C₁₀ alkylene group with x = 2 and z = 0 or with x = 1, z = 1 and R³ = C₁-C₆ -Alkyl- or C₁-C₂₀ acyl radical, or R is a C₆-C₁₀ aryl radical which can be substituted with up to 2 C₃-C₁₈ alkyl radicals, where x = 1 and z = 0;
• an amine of formula IV
  
  R⁴-NH₂ IV
  
  wherein R⁴ is a linear or branched C₁-C₆ alkyl or C₁-C₁₀ hydroxyalkyl radical or corresponds to a radical of the following formula V.
  
  with R⁵ = H or C₁-C₃-alkyl, m = 2 to 4, r = 2 to 10 and q = 0 to 5,
• a bisphenol of formula VI
  
  wherein k = 0 to 3 and R⁶ and R⁷ can independently be H and C₁-C₃-alkyl; or
• of a polyethyleneimine with a molecular weight M _w of 2,000 to 50,000

stands; being the

In each case, radicals are in place of the hydrogens of the alkylphenol-formaldehyde resins, the alcohols, bisphenols, amines or polyethyleneimines and p corresponds to the number of hydrogens to be alkoxylated, characterized in that the alkoxylate of the formula I has a polydispersity Q = $\overline{\text{M}}$

_w / $\overline{\text{M}}$

_n of at least 1.7.

It is essential for the desired properties of the petroleum emulsion splitters according to the invention that the alkoxylate shows the stated polydispersity. This polydispersity is achieved by producing the alkoxylate using a special catalyst.

_w von 2000 bis 50 000 mit Ethylenoxid, Propylenoxid und/oder Butylenoxid umsetzt in Gegenwart eines, gegebenenfalls teilhydrolisierten, Metall-Alkoholats als Katalysator, wobei das Metall aus den Metallen der Gruppen IIA, IIIA, IVB, sowie Zn, Ce und La ausgewählt ist und die Alkoholat-Gruppe 1 bis 8 C-Atome aufweist.The present invention therefore also relates to a process for the preparation of alkoxylates of the above general formula I, which is characterized in that alkylphenol-formaldehyde resins of the above formula II, bisphenols of the above formula VI, alcohols of the above formula III , Amines of formula IV given above or polyethyleneimines with a molecular weight $\overline{\text{M}}$

_w reacted from 2000 to 50,000 with ethylene oxide, propylene oxide and / or butylene oxide in the presence of an optionally partially hydrolyzed metal alcoholate as a catalyst, the metal being selected from the metals from Groups IIA, IIIA, IVB, and Zn, Ce and La and the alcoholate group has 1 to 8 carbon atoms.

In the petroleum emulsion splitters based on alkoxylated compounds known from the prior art, hydroxides of the alkali metals are used as catalysts for the alkoxylation (see, for example, DE-PS 20 13 820, column 5, AII). With these catalysts, as was found in comparative experiments, only polydispersities up to 1.6 are achieved.

It has now surprisingly been found that the crude oil emulsions according to the invention achieve a significantly faster splitting of the crude oil emulsions, and that the splitters according to the invention can be dosed correspondingly lower.

_w/ $\overline{\text{M}}$

_n ist bekanntlich ein Maß für die Molekulargewichtsverteilung von polymeren Verbindungen (siehe z.B. Encyclopedia of Polymer Sci. and Engineering, Vol. 10, S. 4, J. Wiley 1987). Je größer der Wert von Q, desto breiter die Molekulargewichtsverteilung. Für die erfindungsgemäß hergestellten Alkoxilate heißt dies, daß sie eine breitere Molekulargewichtsverteilung zeigen als die bekannten, mit Alkalihydroxid als Katalysator hergestellten Verbindungen.The polydispersity Q = $\overline{\text{M}}$

_w / $\overline{\text{M}}$

_As is known, _n is a measure of the molecular weight distribution of polymeric compounds (see, for example, Encyclopedia of Polymer Sci. and Engineering, Vol. 10, p. 4, J. Wiley 1987). The larger the value of Q, the wider the molecular weight distribution. For the alkoxylates prepared according to the invention, this means that they have a broader molecular weight distribution than the known compounds prepared with alkali hydroxide as a catalyst.

For the alkylphenol-formaldehyde resins, this can also be expressed by the hydroxyl number: while the known alkoxylates have hydroxyl numbers from 130 to 170, the alkoxylates prepared according to the invention have hydroxyl numbers above 170, preferably between 180 and 300.

_w von 2000 bis 50 000, insbesondere von 5000 bis 25 000 eingesetzt.The starting compounds for the preparation of the alkoxylates are alkylphenol-formaldehyde resins of the formula II, alcohols of the formula III, amines of the formula IV, bisphenols of the formula VI or polyethyleneimines with a molecular weight $\overline{\text{M}}$

_{w used} from 2000 to 50,000, in particular from 5000 to 25,000.

Alkylphenol-formaldehyde resins, alcohols and polyethyleneimines are preferred.

As alkylphenol-formaldehyde resins which can be prepared by known processes, in particular those are used which carry an iso-C₄-C₁₂ alkyl radical and in which y = 5 to 11. An iso-C₈-C₁₂ alkyl radical is particularly preferred.

In particular, diols such as e.g. Ethylene glycol, diethylene glycol or butylene glycol, or glycol monoesters such as e.g. Ethylene glycol monoacetate used.

The amines to be used include, in particular, the polyalkylene polyamines, such as Diethylene triamine, triethylene tetramine or tetraethylene pentamine. Alkanolamines are also suitable.

The polyethyleneimines are preferably branched and contain primary, secondary and tertiary amine groups.

Bisphenol A should be mentioned in particular as bisphenol.

All of these compounds are known per se and have been described many times in the literature.

The alkoxylation of the alkylphenol-alkylphenol-formaldehyde resins, the alcohols, bisphenols, amines and polyethyleneimines takes place with ethylene oxide, propylene oxide and / or butylene oxide. Ethylene oxide and / or propylene oxide are preferably used.

The reaction is carried out in an inert solvent, e.g. Toluene or xylene, usually at 100 to 180 ° C. The moles of alkylene oxide are introduced per unit to be alkoxylated or OH or H₂N group, so that n = 3-100, preferably 3 -50, particularly preferably 4-12. In the case of the amines, there is a 2-stage reaction, as is e.g. is described in DE-OS 24 35 713, advantageous. The amount of starting compound and alkylene oxide in relation to the solvent is e.g. chosen so that an 80 wt .-% solution results.

The metal alcoholates according to the invention are used as catalysts, which can be represented by the following formula VII:

Me (OH) _d (OR) _e VII


where Me stands for metals of group IIA, in particular Mg, Ca and Ba, of group IIIA, in particular Al, of group IVB, in particular Ti (group name corresponding to CAS up to 1986), and Zn, Ce or La, d = 0 and the upper limits of d and e depend on the valence of the metal. Aluminum tri or titanium tetra alcoholates are preferably used, in particular aluminum tri (isopropylate).

The metal alcoholates can also be used in conjunction with Zn-alkylene and small amounts of H₂O in hexane (see US 3,384,603).

The amount of the catalyst used, based on the end products, is 0.05 to 5% by weight.

The starting compounds can also be used in a conventional manner, i.e. catalyzed with alkali metal hydroxides, prepared, partially oxyalkylated compounds are used. It is only essential that the required polydispersity is obtained by subsequent alkoxylation using the above-mentioned metal alcoholates according to the invention.

_w- und $\overline{\text{M}}$

_n-Werte wurden gelpermeationschromatographisch bestimmt.The polydispersity Q must be at least 1.7 in order to achieve the desired effect. Q is preferably 1.7-5, particularly preferably 1.8 to 3.0, in particular 1.8 to 2.8. It can be observed that the differences in the Q values between alkoxylates prepared with conventional catalysts and alkoxylates prepared with the catalysts to be used according to the invention are different, depending on which compound RH one starts from. However, the difference between these Q values, based on the same starting compound RH, should be 0.3 or more.

The ones required to calculate Q. $\overline{\text{M}}$

_w - and $\overline{\text{M}}$

_n values were determined by gel permeation chromatography.

Säulenmaterial:

PL-Gel mit 5 µm Teilchengröße

Säulenlänge:

300 cm, Durchmesser 7,5 mm.

The conditions for the GPC analysis were as follows:

Column material:

PL gel with 5 µm particle size

Column length:

300 cm, diameter 7.5 mm.

Detektor:

RI + UV (254 nm).

A column combination of guard column, a column with 100 Å material, 2 columns with 500 Å material and another column with 1000 Å material was used. The internal standard was toluene, the flow was 1 ml / min, the temperature 70 ° C.

Detector:

RI + UV (254 nm).

The feed volume was 20 ul of a 1 wt .-% solutions, solvent THF.

_n- und $\overline{\text{M}}$

_w-Werte wurden mit Hilfe von Eichsubstanzen (Ethoxilate) mittels eines üblichen Rechenprogramms aus dem Chromatogramm ermittelt.The $\overline{\text{M}}$

_n - and $\overline{\text{M}}$

_w values were determined from the chromatogram using calibration substances (ethoxylates) using a standard computer program.

In addition to the alkoxylate A of the general formula I, the petroleum emulsion splitter according to the invention can contain, as further component B, a different alkoxylated polyalkylene polyamine which does not have the Q values according to the invention. Such additional components are known and e.g. described in more detail in DE-PS 27 19 978, for which purpose in this patent reference is made in particular to column 4, B. This additional mixture component is also disclosed in DE-OS 22 27 546.

The weight ratio A to B is preferably 60:40 to 40:60% by weight.

The splitters are advantageously added to the crude oil emulsions in amounts of 1 to 1000 ppm, preferably 10 to 100 ppm, based on the weight of the emulsion to be split, at temperatures between 20 and 80 ° C.

The splitters can be used as solutions because of their better meterability. Mixtures of organic solvents (eg methanol) with water or organic solvents with boiling points between 50 and 200 ° C. can be used as solvents serve, for example toluene, xylenes, tetrahydrofuran, dioxane, lower alcohols and light petroleum fractions of the boiling point mentioned.

If solutions are used, these are expediently adjusted to an active substance content (splitter content) of 0.5 to 50% by weight. During the cleavage, the solutions are preferably added to the crude oils at the probes (in the field). The cleavage then already runs at the temperature of the freshly pumped water-in-oil emulsion at such a rate that the emulsion can be broken on the way to the processing plant. There it is separated in a possibly heated separator and possibly with the help of an electric field without difficulty into pure oil and salt water.

Examples

NPFH:

iso-Nonylphenol-Formaldehyd-Harz

EONP:

mit 4,1 mol EO, KOH-katalysiert, alkoxiliertes iso-Nonyl-phenol-Formaldehyd-Harz

DPFH:

iso-Dodecylphenol-Formaldehyd-Harz

EO:

Ethylenoxid

PO:

Propylenoxid

ATIP:

Aluminium-tri-(isopropylat)

2. Nach dem Stand der Technik (s. DE-PS 27 19 978) wurden auf 782 g (0,0191 Mol) eines Polyethylenimins mit einem Molekulargewicht von ca. 18.000 (44%ige Lösung in H₂O) ca. 500 g Propylenoxid (PO) in einem 2 l-Rührautoklaven mit Stickstoff bei 90 bis 100°C während 600 min bei 6,5 bar aufgepreßt. Anschließend wurde das Wasser im Vakuum entfernt. Man erhielt 852 g Produkt, d.h. die tatsächliche Aufnahme an PO betrug 1,1 Mol pro Ethylenimineinheit im Polyethylenimin.
In einer zweiten Stufe wurden auf 53,4 g Produkt aus Stufe 1 667 g Propylenoxid in Gegenwart von 0,53 g (1 Gew.-%) K-tert.-Butylat in dem Rührautoklaven bei 130 bis 140°C während 36 h bei 7,4 bar aufgepreßt. Das überschüssige Propylenoxid PO wurde anschließend abgezogen. Man erhielt 715 g Produkt, d.h. es wurden 22,8 Mol PO pro Ethylenimineinheit im Polyethylenimin aufgenommen.
In einer dritten Stufe wurden schließlich auf 214,4 g Produkt aus Stufe 2 132 g Ethylenoxid (EO) in Gegenwart von 2,14 g K-tert.-Butylat bei 120 bis 130°C während 150 min bei 6,8 bar aufgepreßt und das überschüssige EO abgezogen. Man erhielt 361 g Produkt, d.h. die tatsächliche Aufnahme an EO betrug 21,9 Mol pro Ethylenimineinheit im Polymeren.
Das Endprodukt wies einen Q-Wert von 1,4 auf.
3. Bei der Herstellung des erfindungsgemäßen Alkoxilats wurden zunächst die Stufen 1 und 2 wie unter 2. angegeben durchgeführt und dann das K-tert.-Butylat abgetrennt.
Auf 214,4 g des so erhaltenen Produkts wurden 132 g EO in Gegenwart von 6,43 g Aluminium-tri-isopropylat (≙ 3 Gew.-%) im Rührautoklaven mit Stickstoff bei 120 bis 130°C während 870 min bei 9,4 bar aufgepreßt und anschließend überschüssiges EO abgezogen. Man erhielt 365 g Produkt, d.h. die tatsächliche Aufnahme an EO betrug 21,8 Mol pro Ethylenimineinheit im Polyethylenimin. Dieses Produkt wies einen Q-Wert von 1,7 auf.
B) Anwendungstechnische Beispiele
Die nach A)1. erhaltenen Alkoxilate wurden mit einem oxalkylierten Polyalkylenpolyamin B, hergestellt gemäß DE-PS 27 19 978, Spalte 4, B, im Verhältnis 1:1 gemischt und auf ihre Wirksamkeit als Erdölemulsionsspalter geprüft.
Dann wurden die jeweils angegebenen Mengen des entsprechenden Alkoxilats zu 100 g einer der in Tabelle 2 angegebenen Rohölemulsionen zugesetzt. Die Mischungen wurden jeweils in einem Glaskolben mit einem mechanischen Rührer bei 55°C 10 Minuten mit einer Rührgeschwindigkeit von 500 UpM gerührt und in einen 100 ml Standzylinder eingegossen. Der Standzylinder wurde in ein Wasserbad mit der angegebenen Prüftemperatur gestellt und die Wasserabscheidung im Verlauf von 4 Stunden beobachtet und aufgezeichnet.

A) Preparation examples of alkoxylates
1. The starting compounds given in Table 1 were reacted with the moles of alkylene oxide also given using the respective catalyst in toluene at the temperatures given. The polydispersities Q obtained are also shown in Table 1. Table 1 Alkoxylate Starting product Moles of alkylene oxide catalyst Q T in ° C A1 NPFH 4.1 EO ATIP 2.4 120-130 A2 EONP 5.0 PO ATIP 1.9 130-140 A3 NPFH 9.7 PO ATIP 2.4 130-140 A4 NPFH 4.9 EO ATIP 2.7 120-130 A5 DPFH 9.3 EO ATIP 2.5 120-130 A6 DPFH 7.8 PO ATIP 2.1 130-140 A7 DPFH 6.8 EO ATIP 2.0 120-130 Comparative examples: Alkoxylate Starting product Moles of alkylene oxide catalyst Q a1 NPFH 4.1 EO KOH 1.5 a2 EONP 4.9 PO KOH 1.6 a3 NPFH 5.6 EO + 1.8 PO KOH 1.4 a4 NPFH 15.1 EO + 15.0 PO KOH 1.5 a5 NPFH 9.8 PO KOH 1.5 Abbreviations:

NPFH:

iso-nonylphenol formaldehyde resin

EONP:

with 4.1 mol EO, KOH-catalyzed, alkoxylated iso-nonyl-phenol-formaldehyde resin

DPFH:

iso-dodecylphenol formaldehyde resin

EO:

Ethylene oxide

PO:

Propylene oxide

ATIP:

Aluminum tri- (isopropylate)

2. According to the prior art (see DE-PS 27 19 978) about 500 g propylene oxide (782 g (0.0191 mol) of a polyethyleneimine with a molecular weight of about 18,000 (44% solution in H₂O) ( PO) in a 2 l stirred autoclave with nitrogen at 90 to 100 ° C for 600 min at 6.5 bar. The water was then removed in vacuo. 852 g of product were obtained, ie the actual PO uptake was 1.1 mol per ethyleneimine unit in the polyethyleneimine.
In a second stage, 667 g of propylene oxide were added to 53.4 g of product from stage 1 in the presence of 0.53 g (1% by weight) of K-tert-butoxide in the stirred autoclave at 130 to 140 ° C. for 36 hours 7.4 bar pressed. The excess propylene oxide PO was then removed. 715 g of product were obtained, ie 22.8 mol of PO per ethyleneimine unit were taken up in the polyethyleneimine.
In a third stage, 132 g of ethylene oxide (EO) were finally injected onto 214.4 g of product from stage 2 in the presence of 2.14 g of K-tert-butoxide at 120 to 130 ° C. for 150 min at 6.8 bar and the excess EO is deducted. You got 361 g of product, ie the actual uptake of EO was 21.9 mol per ethyleneimine unit in the polymer.
The end product had a Q value of 1.4.
3. In the preparation of the alkoxylate according to the invention, stages 1 and 2 were first carried out as indicated under 2. and then the K-tert-butoxide was separated off.
To 214.4 g of the product obtained in this way, 132 g of EO were present in the presence of 6.43 g of aluminum tri-isopropylate (≙ 3% by weight) in a stirred autoclave with nitrogen at 120 to 130 ° C. for 870 min at 9.4 pressed on bar and then removed excess EO. 365 g of product were obtained, ie the actual uptake of EO was 21.8 mol per ethyleneimine unit in the polyethyleneimine. This product had a Q value of 1.7.
B) Application engineering examples
According to A) 1. The alkoxylates obtained were mixed with an oxalkylated polyalkylene polyamine B, prepared according to DE-PS 27 19 978, column 4, B, in a ratio of 1: 1 and tested for their effectiveness as a petroleum emulsion breaker.
Then the amounts of the corresponding alkoxylate given in each case were added to 100 g of one of the crude oil emulsions shown in Table 2. The mixtures were each stirred in a glass flask with a mechanical stirrer at 55 ° C. for 10 minutes at a stirring speed of 500 rpm and poured into a 100 ml standing cylinder. The standing cylinder was placed in a water bath at the specified test temperature and the water separation was observed and recorded over a period of 4 hours.

In the following test, the alkoxylates were tested under conditions which are otherwise the same as those given in Table 2, without the additional component B: A2 120 Northern German Oil II 50 13 a2 120 Northern German Oil II 50 14

The results are shown in Table 3.

The even numbered examples are the comparative examples

The results show that the petroleum emulsion splitters according to the invention result in significant improvements in the splitting speed with a large number of different crude oil emulsions.

Claims (8)

1. An oil demulsifier based on an alkoxylate of the formula I

   

   where A is ethylene, propylene and/or butylene, n is 3-100 and R is the radical

   of an alkylphenol/formaldehyde resin of the formula II

   

   where R¹ is branched C₃-C₁₈-alkyl and y is from 3 to 30, of an alcohol of the formula III

   

   where either R is C₁-C₂₀-alkyl, x is 1 and z is 0 or R is C₂-C₁₀-alkylene, x is 2 and z is 0 or x is 1, z is 1 and R³ is C₁-C₆-alkyl or C₁-C₂₀-acyl, or R is C₆-C₁₀-aryl which may be substituted by up to 2 C₃-C₁₈-alkyl radicals, x is 1 and z is 0,
   of an amine of the formula IV
   
           R⁴-NH₂     IV
   
   

   where R⁴ is a straight-chain or branched C₁-C₆-alkyl or C₁-C₁₀-hydroxyalkyl radical or is a radical of the following formula V

   

   where R⁵ is H or C₁-C₃-alkyl, m is from 2 to 4, r is from 2 to 10 and q is from 0 to 5,
   of a bisphenol of the formula VI

   

   where k may be from 0 to 3 and R⁶ and R⁷ independently of one another may each be H or C₁-C₃-alkyl,
   or of a polyethyleneimine having a molecular weight $\overline{\text{M}}$

   

   _w of from 2,000 to 50,000,

   where the

   

   radicals are each present in place of those hydrogens of the alkylphenol/formaldehyde resins, alcohols, bisphenols, amines or polyethylene-imines which are on the oxygen or nitrogen and p is the number of hydrogens to be alkoxylated, wherein the alkoxylate of the formula I has a polydispersity Q = $\overline{\text{M}}$

   

   _w/ $\overline{\text{M}}$

   

   _n of at least 1.7.
2. An oil demulsifier as claimed in claim 1, wherein R is a radical of an alkylphenol/formaldehyde resin of the formula II, where R¹ is iso-C₄-C₁₂-alkyl, y is from 5 to 11 and/or n is from 3 to 50, preferably from 4 to 12.
3. An oil demulsifier as claimed in claim 1, wherein R is an alcohol of the formula III, where x is 2 and z is 0 or x is 1, z is 1 and R³ is C₁-C₃-acyl.
4. An oil demulsifier as claimed in claim 1, wherein Q is from 1.7 to 5.0, preferably from 1.8 to 3.0.
5. An oil demulsifier as claimed in claim 1, which, in addition to the alkoxylate of the formula I, contains a different oxyalkylated polyalkylenepolyamine.
6. An oil demulsifier as claimed in claim 1, wherein A is an ethylene and/or propylene radical.
7. A process for the preparation of alkoxylates of the formula I as claimed in claim I, wherein an alkylphenol/formaldehyde resin of the formula II as claimed in claim 1, a bisphenol of the formula VI as claimed in claim 1, an alcohol of the formula III as claimed in claim 1, an amine of the formula IV as claimed in claim 1 or a polyethyleneimine having a molecular weight $\overline{\text{M}}$

   

   _w of from 2,000 to 50,000 is reacted with ethylene oxide, propylene oxide and/or butylene oxide in the presence of an unhydrolyzed or partly hydrolyzed metal alcoholate as a catalyst, the metal being selected from the metals of the groups IIA, IIIA and IVB and Zn, Ce and La and the alcoholate group being of 1 to 8 carbon atoms.
8. A process as claimed in claim 7, wherein the metal is Al or Ti and the alcoholate group is a C₂-, n-or iso-C₃-, n- or iso-C₄- or tert-C₄- group.