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 13 to 17 mol % of at least one acrylic ester or vinyl ester having a C1-C18-alkyl radical and a melt viscosity V140 of not more than 80 mPas, 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	35 mPas	3.9	16.6 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 determined 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	25	2
	(1:0.5:0.5)	amine
B2	MSA-co-C14/16-α-olefin	C14	25.0	57
	(1:0.5:0.5)	amine

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	−8	SoyaME RME 30:70
	E2	−7	RME/PME 85:15
	E3	−11	RME/AME 60:40
	E4	−10	RME/AME 50:50
	E5	−8	RME/AME 40:60
	E6	−8	RME/AME 45:55
	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
	C16:0	6.53	6.21	6.74	7.33	8.13	7.76
	C18:0	1.19	2.36	2.71	2.97	3.32	3.16
	C18:1	45.19	48.73	52.56	50.84	45.36	46.77
	C18:2	36.33	28.77	26.45	28.17	32.27	31.00
	C18:3	8.37	9.18	6.36	5.49	5.45	5.89
	C20:1/	0.79	1.25	1.14	1.04	0.97	1.03
	2/3
	C20:0	0.39	0.57	0.58	0.56	0.53	0.57
	C22:0	0.15	0.39	0.48	0.51	0.50	0.49

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	Poly-	2000	3000	4000
Ex.	polymer	copolymer	acrylate	ppm	ppm	ppm
1	B1	A2	—	−18	−22	−20
2 (C)	B1	A1	—	−12	−16	−10
3	B1	A2	C3	−18	−21	−21

TABLE 7
CFPP testing in test oil E2
	Comb	Ethylene	Poly-	2000	3000	4000
Ex.	polymer	copolymer	acrylate	ppm	ppm	ppm
4 (C)	B1	A4	—	−6	−10	−10
5	B1	A2	C1	−8	−10	−11

TABLE 8
CFPP testing in test oil E3
	Comb	Ethylene		2000
Ex.	polymer	copolymer	Polyacrylate	ppm	3000 ppm
6	B1	A2	—	−20	−23
7 (c)	B1	A4	—	−17	−19

TABLE 9
CFPP testing in test oil E4
		Ethylene		2000
Ex.	Comb polymer	copolymer	Polyacrylate	ppm	3000 ppm
8	B1	A2	—	−17	−22
9 (C)	B2	A3	—	−14	−17

TABLE 10
CFPP testing in test oil E5
	Comb	Ethylene		2000	3000
Ex.	polymer	copolymer	Polyacrylate	ppm	ppm
10	B1	A2	—	−13	−18
11	B1	A2	C2	−13	−18
12 (C)	B1	A3	—	−11	−13

TABLE 11
CFPP testing in test oil E6
		Comb	Ethylene
	Ex.	polymer	copolymer	Polyacrylate	4000 ppm
	13	B1	A2	—	−19
	14	B1	A2	C2	−19
	15 (C)	B1	A3	—	−16

Claims

1. A fuel oil additive comprising A) a copolymer of ethylene and from 13 to 17 mol % of at least one acrylic ester or vinyl ester having a C1-C18-alkyl radical and a melt viscosity V140 of not more than 80 mPas, 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 15 to 17 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 6 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 80 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.