Cold flow improvers for vegetable or animal fuel oils

Abstract

The present invention relates to a fuel oil additive comprising A) a copolymer of ethylene and from 18 to 35 mol % of at least one acrylic ester or vinyl ester having a C1-C18-alkyl radical and a degree of branching of less than 5 CH3/100 CH2 groups, andB) a comb polymer comprising structural units formed fromB1) at least one olefin as monomer 1, which bears at least one C8-C18-alkyl radical on the olefinic double bond, andB2) at least one ethylenically unsaturated dicarboxylic acid as monomer 2, which bears at least one C8-C16-alkyl radical bonded via an amide and/or imide group, in which the parameter Q

Description

EXAMPLES

TABLE 1
Characterization of the ethylene copolymers used
			CH3/100	Content of
Example	Comonomer(s)	V140	CH2	vinyl ester
A1 (C)	Ethylene/VAC/	110 mPas	4.2	13.3 mol %
	vinyl
	neodecanoate
A2	Ethylene/VAC	52 mPas	4.0	20.2 mol %
A3 (C)	Ethylene/VAC	154 mPas	3.0	16.7 mol %
A4 (C)	Ethylene/VAC	125 mPas	3.0	13.8 mol %
VAC = vinyl acetate

The vinyl ester content was measured by means of pyrolysis and subsequent titration.

The viscosity (V₁₄₀) was measured with a Haake Reostress 600 viscometer.

The degree of branching (CH₃/100CH₂) was measured on a ¹H NMR unit at 400 MHz in CDCl₃, and calculated by means of integration of the individual signals.

TABLE 2
Characterization of the comb polymers used
				Acid
				number
Example	Comonomers	Amine	Q	[mg KOH/g]
B1	MSA-co-C14/16-α-olefin	C12 amine	25	2
	(1:0.5:0.5)
B2	MSA-co-C14/16-α-olefin	C14 amine	25.0	57
	(1:0.5:0.5)

TABLE 3
Acrylates
C1 Poly(octadecyl acrylate), K value 32
C2 Poly(behenyl acrylate), K value 18

TABLE 4
Characterization of the test oils
	Oil No.:	CFPP [° C.]	Composition
	E1	−16	RME
	E2	−13	RME/AME 90:10
	E3	−11	RME/AME 80:20
	E4	−12	RME/SoyaME 92:8
	E5	−12	RME/SoyaME 80:20
	E6	−9	RME/SoyaME 60:40
	E7	−8	RME/PME 85:15
	SoyaME = soya methyl ester
	RME = rapeseed oil methyl ester
	PME = palm oil methyl ester
	AME = used oil methyl ester

TABLE 5
Methyl ester distribution of the test oils
	E1	E2	E3	E4	E5	E6	E7
C16:0	4.27	6.81	5.58	5.22	5.8	7.14	11.18
C18:0	0.92	2.35	2.35	1.01	1.94	2.25	2.25
C18:1	59.48	54.55	54.88	55.94	53.08	43.93	52.87
C18:2	29.56	20.79	21.84	23.48	25.27	32.04	19.43
C18:3	1.58	9.58	9.58	9.59	8.31	7.47	8.81
C20:1/2/3	1.48	1.49	1.61	1.43	1.33	1.09	1.23
C20:0	0.63	0.66	0.67	0.64	0.65	0.6	0.63
C22:0	0.23	0.39	0.44	0.39	0.39	0.39	0.34

In the tables which follow, the mixing ratio according to weight of the additives A, B and C is A:B=4:1, or, when C is present in the mixtures, A:B:C=4:1:0.2. The total amount of additive is evident from the top row of the table.

TABLE 6
CFPP testing in test oil E1
	Comb	Ethylene			1200	1500
Ex.	polymer	copolymer	Polyacrylate	1000 ppm	ppm	ppm
1	B1	A2	—	−23	−26	−28
2 (C)	B1	A1	—	−18	−20	−22

TABLE 7
CFPP testing in test oil E2
	Comb	Ethylene			1200	1500
Ex.	polymer	copolymer	Polyacrylate	1000 ppm	ppm	ppm
3 (C)	B1	A1	—	−13	−13	−16
4	B1	A2	C1	−14	−17	−22
5	B1	A2	—	−13	−18	−22
6 (C)	B2	A3	—	−13	−14	−15

TABLE 8
CFPP testing in test oil E3
	Comb	Ethylene	Poly-	800	1000	1500
Ex.	polymer	copolymer	acrylate	ppm	ppm	ppm
7 (C)	B1	A1	—	−11	−18	−22
8	B1	A2	—	−20	−23	−24
9	B1	A2	C1	−19	−22	−25
10 (C)	B1	A3	—	−11	−17	−16

TABLE 9
CFPP testing in test oil E4
	Comb	Ethylene	Poly-	1200	1500	2000
Ex.	polymer	copolymer	acrylate	ppm	ppm	ppm
11 (C)	B1	A1	—	−17	−20	−23
12	B1	A2	—	−20	−22	−22
13	B1	A2	C1	−20	−23	−22
14 (C)	B1	A3	—	−16	−18	−18
15 (C)	B2	A3	—	−15	−17	−18

TABLE 10
CFPP testing in test oil E5
		Comb	Ethylene	Poly-	1500	2000
	Ex.	polymer	copolymer	acrylate	ppm	ppm
	16 (C)	B1	A1	—	−19	−21
	17	B1	A2	—	−20	−23
	18 (C)	B1	A4	—	−17	−19

TABLE 11
CFPP testing in test oil E6
		Ethylene
Ex.	Comb polymer	copolymer	Polyacrylate	2000 ppm
21(C)	B1	A1	—	−18
23	B1	A2	—	−21

TABLE 12
CFPP testing in test oil E7
	Comb	Ethylene
Ex.	polymer	copolymer	Polyacrylate	4000	5000
24 (C)	B1	A1	—	−11	−14
26	B1	A2	—	−14	−16

Claims

1. A fuel oil additive comprising A) a copolymer of ethylene and from 18 to 35 mol % of at least one acrylic ester or vinyl ester having a C1-C18-alkyl radical and a degree of branching of less than 5 CH3/100 CH2 groups, andB) a comb polymer comprising structural units formed fromB1) at least one olefin as monomer 1, which bears at least one C8-C18-alkyl radical on the olefinic double bond, andB2) at least one ethylenically unsaturated dicarboxylic acid as monomer 2, which bears at least one C8-C16-alkyl radical bonded via an amide and/or imide group,in which the parameter Q

2. The fuel oil additive as claimed in claim 1, wherein Q assumes values of from 24 to 26.

3. The fuel oil additive as claimed in claim 1, wherein constituent A) comprises from 18.5 to 27 mol % of at least one vinyl ester.

4. The fuel oil additive of claim 1, wherein constituent A) comprises from 0.5 to 10 mol % of olefins having from 3 to 10 carbon atoms.

5. The fuel oil additive of claim 1, wherein the degree of branching of constituent A) is less than 4 CH3/100 CH2 groups, determined by means of 1H NMR spectroscopy.

6. The fuel oil additive of claim 1, wherein the at least one olefin which forms constituent B1) is an α-olefin.

7. The fuel oil additive of claim 1, wherein a molar ratio of comonomer B1) to comonomer B2) in copolymer B) is between 1.5:1 and 1:1.5.

8. The fuel oil additive of claim 1, wherein copolymer B, as well as comonomers B1) and B2), further comprises up to 20 mol % of a further comonomer other than B1) and B2), selected from the group consisting of an olefin having from 2 to 50 carbon atoms, an allyl polyglycol ether, a C1-C30-alkyl (meth)acrylate a vinylaromatic or a C1-C20-alkyl vinyl ether, and a polyisobutene having molecular weights of up to 5000 g/mol.

9. The fuel oil additive of claim 1, wherein constituent A) has a melt viscosity V140 of from 5 to 100 mPas.

10. The fuel oil additive of claim 1, wherein constituent A) has a molecular weight of from 1000 to 10 000 g/mol.

11. The fuel oil additive of claim 1, in which constituent B) has a molecular weight Mw of from 1200 to 200 000 g/mol.

12. A fuel oil composition comprising a fuel oil of vegetable or animal origin and the fuel oil additive of claim 1.

13. The fuel oil composition as claimed in claim 12, wherein the fuel oil further comprises a mixture of fatty acid esters of C1- to C4-alcohols.

14. The fuel oil composition as claimed in claim 13, wherein the fatty acid esters include stearic acid methyl ester and palmitic acid methyl ester in a proportion of at least 7% by weight.

15. A process for improving the cold behavior of fuel oils of vegetable or animal origin, said process comprising admixing a portion of the fuel oil additive of claim 1 with said fuel oil.