Additives For Low-Sulfur Marine Diesel
20170233670 · 2017-08-17
Assignee
Inventors
Cpc classification
C10L1/146
CHEMISTRY; METALLURGY
C10L2200/0438
CHEMISTRY; METALLURGY
C10L2230/14
CHEMISTRY; METALLURGY
C10L1/1641
CHEMISTRY; METALLURGY
C10L2270/026
CHEMISTRY; METALLURGY
International classification
Abstract
This invention relates to a fuel oil composition, containing a low-sulfur marine diesel having a sulfur content of less than 1 wt. % and (A) at least one ethylene copolymer and (B) at least one comb polymer.
Claims
1. A fuel oil composition comprising a low-sulfur marine diesel having a sulfur content of less than 1% by weight and (A) at least one ethylene copolymer and (B) at least one comb polymer.
2. The fuel oil composition as claimed in claim 1, in which the untreated low-sulfur marine diesel has a pour point of +6° C. or higher.
3. The fuel oil composition as claimed in claim 1 and/or 2, in which the low-sulfur marine diesel has a viscosity of not more than 200 mm.sup.2/s at 40° C.
4. The fuel oil composition as claimed in claim 1 and/or 2, in which the low-sulfur marine diesel has a viscosity of not more than 11 mm.sup.2/s at 40° C.
5. The fuel oil composition as claimed in one or more of claims 1 to 4, in which the low-sulfur marine diesel comprises a residue from the further processing of a mineral oil distillate.
6. The fuel oil composition as claimed in one or more of claims 1 to 5, in which the low-sulfur marine diesel has a sulfur content of 0.1% by weight or lower.
7. The fuel oil composition as claimed in one or more of claims 1 to 6, wherein the residue from the further processing of a mineral oil distillate which is used for production of the low-sulfur marine diesel contains at least 3% by weight of paraffins having more than 24 carbon atoms.
8. The fuel oil composition as claimed in one or more of claims 1 to 7, wherein the residue from the further processing of a mineral oil distillate which is used for production of the low-sulfur marine diesel has a pour point of 9° C. or higher.
9. The fuel oil composition as claimed in one or more of claims 1 to 8, wherein the ethylene copolymer (A) contains, as well as ethylene, 8.0 to 17 mol % of one or more vinyl and/or (meth)acrylic esters.
10. The fuel oil composition as claimed in one or more of claims 1 to 8, wherein the ethylene copolymer (A) contains, as well as ethylene and 8.0 to 17 mol % of one or more vinyl and/or (meth)acrylic esters, also 0.1 to 5 mol % of one or more olefins having 3-8 carbon atoms.
11. The fuel oil composition as claimed in claim 10, in which the olefin is propene.
12. The fuel oil composition as claimed in one or more of claims 1 to 11, in which the ethylene copolymer (A) contains one or more vinyl esters derived from carboxylic acids having 3 to 12 carbon atoms.
13. The fuel oil composition as claimed in claim 12, in which the vinyl ester is vinyl acetate.
14. The fuel oil composition as claimed in one or more of claims 1 to 13, in which the number-average molecular weight M.sub.n of the ethylene copolymer (A) is between 1000 and 7000 g/mol.
15. The fuel oil composition as claimed in one or more of claims 1 to 14, wherein the comb polymer (B) includes at least 40 mol % of repeat structural units (B1) that bear C.sub.10-C.sub.28-alkyl radicals.
16. The fuel oil composition as claimed in one or more of claims 1 to 15, wherein the comb polymer (B) comprises structural units B1 which derive from C.sub.10-C.sub.28-alkyl esters of unsaturated mono- and dicarboxylic acids, C.sub.10-C.sub.28-alkyl vinyl esters, C.sub.10-C.sub.28-alkyl vinyl ethers, C.sub.10-C.sub.28-alkyl allyl ethers and/or linear C.sub.12-C.sub.30-α-olefins.
17. The fuel oil composition as claimed in one or more of claims 1 to 16, wherein at least 20 mol % of the alkyl radicals bonded to the repeat structural units (B1) have 12 to 16 carbon atoms and at least 5 mol % have alkyl radicals having 18 or more carbon atoms.
18. The fuel oil composition as claimed in one or more of claims 1 to 17, wherein the sum S
19. The fuel oil composition as claimed in one or more of claims 1 to 18, wherein the carbon chain length distribution in the alkyl radicals of the structural units (B1) is implemented in one polymer.
20. The fuel oil composition as claimed in one or more of claims 1 to 18, wherein the carbon chain length distribution in the alkyl radicals of the structural units (B1) is implemented by mixing two or more polymers.
21. The fuel oil composition as claimed in one or more of claims 1 to 20, wherein the comb polymer (B) contains 1 to 60 mol % of repeat structural units (B2) other than the structural units (B1).
22. The fuel oil composition as claimed in claim 21, wherein the repeat structural units (B2) derive from unsaturated mono- and dicarboxylic acids or their C.sub.1- to C.sub.9-alkyl esters, C.sub.1-C.sub.9-alkyl vinyl esters, C.sub.1-C.sub.9-alkyl vinyl ethers, C.sub.1-C.sub.9-alkyl allyl ethers, linear C.sub.3-C.sub.8-α-olefins and/or branched C.sub.4-C.sub.50-olefins.
23. The fuel oil composition as claimed in one or more of claims 1 to 22, in which the number-average molecular weight of the comb polymers (B) is between 1000 and 100 000 g/mol.
24. The fuel oil composition as claimed in one or more of claims 1 to 23, in which the comb polymers (B) are selected from a) homo- and copolymers of C.sub.10-C.sub.28-alkyl vinyl esters, C.sub.10-C.sub.28-alkyl vinyl ethers and unsaturated C.sub.10-C.sub.28-alkyl monocarboxylates, b) copolymers, esterified with C.sub.10-C.sub.28 alcohols, of unsaturated dicarboxylic acids or anhydrides thereof with C.sub.12-C.sub.28-α-olefins, C.sub.10-C.sub.28-alkyl acrylates, C.sub.10-C.sub.28-alkyl methacrylates, C.sub.10-C.sub.28-alkyl vinyl esters and/or C.sub.10-C.sub.28-alkyl vinyl ethers, c) C.sub.10-C.sub.28-alkyl fumarate-C.sub.1-C.sub.5-alkyl vinyl ester copolymers and d) polymers of C.sub.12-C.sub.30-α-olefins.
25. The fuel oil composition as claimed in one or more of claims 21 to 24, in which the monomers B1 and B2 in the comb polymer (B) add up to 100 mol %.
26. The fuel oil composition as claimed in one or more of claims 1 to 25, containing a sum total of 0.001% to 2% by weight of the additive components (A) and (B).
27. The fuel oil composition as claimed in one or more of claims 1 to 26, wherein the fuel oil composition contains, per part by weight of the ethylene copolymer A), 0.05 to 20 parts by weight of the comb polymer B).
28. The fuel oil composition as claimed in one or more of claims 1 to 27, containing, based on the total amount of A) and B), less than 10% by weight of a nitrogen compound effective as a paraffin dispersant in middle distillates.
29. The use of an additive comprising constituents (A) and (B) as described in one or more of claims 1 and 9 to 27 for dispersion of the paraffins that precipitate out of low-sulfur marine diesel having a sulfur content of less than 1% by weight on storage below the cloud point.
30. The use as claimed in claim 29, wherein a total of between 10 and 20 000 ppm by weight of additive components (A) and (B) are added to the low-sulfur marine diesel.
31. The use of a comb polymer (B) for dispersion of the paraffins that precipitate out of a low-sulfur marine diesel containing at least one ethylene copolymer (A) below the cloud point.
32. The fuel oil composition as claimed in any of claims 1 to 28, wherein the low-sulfur marine diesel contains not more than 5% by weight of a residue from the processing of a desulfurized heavy gas oil.
33. A method of dispersing paraffins which precipitate out of low-sulfur marine diesel having a sulfur content of 1% by weight or lower on storage at temperatures below the cloud point, by adding to the low-sulfur marine diesel an ethylene copolymer (A) and a comb polymer (B) as described in one or more of claims 9 to 27.
34. A method of dispersing paraffins which precipitate out of a low-sulfur marine diesel having a sulfur content of 1% by weight or lower on storage below the cloud point, wherein the low-sulfur marine diesel contains an ethylene copolymer (A), by adding a comb polymer (B) as described in one or more of claims 15 to 25.
Description
EXAMPLES
[0090] To assess paraffin dispersion in low-sulfur marine diesel, the components characterized in table 1 were mixed to give the marine diesels listed in table 2. The content of n-paraffins having 25 to 80 carbon atoms is determined by means of gas chromatography (GC) or high-temperature GC, and the sulfur content by means of wavelength-dispersive x-ray fluorescence analysis according to ISO 14596.
TABLE-US-00001 TABLE 1 Characterization of the components used for the production of low-sulfur marine diesel Gas UCO UCO Kerosene Diesel oil (I) (II) Distillation [° C.] Initial boiling 189 164 196 284 266 point 50% 207 261 337 455 437 95% 251 348 389 543 510 Final boiling 263 358 396 570 530 point Cloud <−40 −6.8 14.1 33 13.9 point [° C.] Pour <−50 −21 12 27 12 point [° C.] Viscosity @ 2.0 3.2 9.8 23.4 21.2 40° C. [mm.sup.2/s] S content <2 5 8 92 148 [ppm] Density @ 0.815 0.8385 0.848 0.856 0.843 15° C. [g/cm.sup.3] n-Paraffins <0.1 0.6 1.9 8.0 13.1 C.sub.25-C.sub.80 [%]
TABLE-US-00002 TABLE 2 Characterization of the low-sulfur marine diesels produced from the components from table 1 Component Method Test oil 1 Test oil 2 Test oil 3 Kerosene [%] 12 — — Diesel [%] 27 — — Gas oil [%] — 65 74 UCO (I) [%] 61 — — UCO (II) [%] — 35 26 Density @ [g/cm.sup.3] ASTM 0.858 0.849 0.845 20° C. D-4052 Viscosity @ [cSt] ISO 3014 10.5 8.9 8.4 40° C. Cloud point [° C.] ISO 3015 23.9 15.6 13.9 Pour point [° C.] ASTM D-97 21 12 12 S content [ppm] ISO 14596 58 62 45
Additives Used
[0091] Ethylene copolymers A) used are ethylene copolymers prepared by means of high-pressure bulk polymerization, having the properties listed in table 3. The comonomer content is determined by means of 1H NMR spectroscopy; as a measure of the molecular weight, the viscosity of the solvent-free polymer is determined at 140° C. The molecular weights are determined by means of GPC in THF against poly(styrene) standards. The polymers are used in the form of 65% by weight concentrates or, in the case of A2, as a 35% concentrate in relatively high-boiling organic solvent.
TABLE-US-00003 TABLE 3 Ethylene copolymers used (A) V.sub.140 Mn Mw Polymer Comonomer content [mPas] [g/mol] [g/mol] A1 13.3 mol % VAc 125 3430 8130 A2 11.2 mol % VAc n.d. 12 800 237 000 A3 11.2 mol % VAc 280 4600 12 300 A4 16.6 mol % VAc 50 2100 3300 A5 14.0 mol % VAc 115 3300 8100 1.6 mol % VeoVa A6 14.0 mol % VAc 170 3900 9000 2.8 propene CH.sub.3 per 100 aliph. CH.sub.2 groups VAc = vinyl acetate; VeoVa ® = vinyl neononanoate; n.d. = not determined
[0092] Comb polymers used were polymers prepared by known processes. The essentially alternating copolymers B1 to B3 and B8 to B10 formed from 50 mol % of maleic anhydride (MA) and 50 mol % of linear α-olefin are prepared in a free-radically initiated solution polymerization in organic solvent and then esterified with 2 mol of the alcohol mixture specified in table 4. The polyalkyl acrylates B4, B5 and B11 and copolymer B6 were prepared in a free-radically initiated solution polymerization. The olefin copolymer B7 was prepared in an anionic polymerization. The composition of the alcohols and olefins relates to the mol % of the components in the respective mixture. The comb polymers are used in the form of 50% concentrates in relatively high-boiling aromatic solvent.
TABLE-US-00004 TABLE 4 A Comb polymers used (B) B1: Poly(MA-co-C.sub.18-α-olefin), esterified with 2 mol of an alcohol mixture of chain length distribution 80% C.sub.14—OH, 1% C.sub.18—OH, 13% C.sub.20—OH, and 6% C.sub.22—OH per mole of anhydride group. Sum S = 15.5 B2: Poly(MA-co-C.sub.18-αOlefin), esterified with 2 mol of an alcohol mixture of 43% C.sub.18—OH, 12% C.sub.20—OH and 45% C.sub.22—OH per mole of anhydride group, sum S = 19.5 B3: Poly(MA-co-C.sub.18-α-olefin), esterified with 2 mol of an alcohol mixture of 5% C.sub.18—OH, 62% C.sub.20—OH, 29% C.sub.22—OH and 4% C.sub.24—OH OH per mole of anhydride group. Sum S = 19.1 B4: Poly(alkyl acrylate) formed from 32 mol % of tetradecyl acrylate, 20 mol % of hexadecyl acrylate, 2 mol % of octadecyl acrylate, 26 mol % of eicosyl acrylate, 15 mol % of docosyl acrylate and 5 mol % of tetracosyl acrylate. Sum S = 17.7 B5: Poly(alkyl acrylate) formed from 15 mol % of dodecyl acrylate, 45 mol % of tetradecyl acrylate, 20 mol % of hexadecyl acrylate, 2 mol % of octadecyl acrylate, 12 mol % of eicosyl acrylate, 6 mol % of docosyl acrylate. Sum S = 15.4 B6: Copolymer formed from approximately equal molar proportions of a fumaric diester which has been prepared by esterification of fumaric acid with an alcohol mixture of 60 mol % of C.sub.14—OH, 29 mol % of C.sub.16—OH, 1 mol % of C.sub.18—OH, 7 mol % of C.sub.20—OH and 3 mol % of C.sub.22—OH, and vinyl acetate. Sum S = 15.3 B7: Copolymer formed from 30.2 mol % of hexadecene, 30.0 mol % of octadecene, 19.0 mol % of eicosene, 13.5 mol % of docosene, 6.5 mol % of tetracosene and 0.8 mol % of hexacosene. Sum S = 16.8 B8 (comp.): Poly(MA-co-C.sub.16/18-olefin) having equal proportions of C.sub.16 and C.sub.18 olefin, esterified with 2 mol of an alcohol mixture of 10% C.sub.12—OH, 32% C.sub.14—OH and 58% C.sub.16—OH per mole of anhydride groups. Sum S = 14.9 B9 (comp.): Poly(MA-co-C.sub.18-α-olefin), esterified with 2 mol of an alcohol mixture of chain length distribution 15% C.sub.10—OH, 46% C.sub.12—OH and 39% C.sub.14—OH per mole of anhydride groups. Sum S = 12.6 B10 (comp.): Poly(MA-co-C.sub.20/24-olefin) with 3% C.sub.18—, 44% C.sub.20—, 35% C.sub.22— and 18% C.sub.24-α-olefin, esterified with 2 mol of an alcohol mixture of 5% C.sub.18—OH, 62% C.sub.20—OH, 29% C.sub.22—OH and 4% C.sub.24—OH per mole of anhydride groups. Sum S = 20.2 B11 (comp.): Poly(alkyl acrylate) formed from 7% decyl acrylate, 74% dodecyl acrylate and 19% tetradecyl acrylate. Sum S = 11.5 B Alkyl chain distribution in the side chains of the comb polymers (B), mol % C.sub.10 C.sub.12 C.sub.14 C.sub.16 C.sub.18 C.sub.20 C.sub.22 C.sub.24 B1 53.3 33.3 0.7 8.7 4.0 B2 33.3 28.7 8.0 30.0 B3 33.3 3.3 41.3 19.3 2.7 B4 32.0 20.0 2.0 26.0 15.0 5.0 B5 15.0 45.0 20.0 2.0 12.0 6.0 B6 60.0 29.0 1.0 7.0 3.0 B7 30.2 30.0 19.0 13.5 6.5 0.8 B8 (comp.) 3.3 18.7 78.0 B9 (comp.) 10.0 30.7 26.0 33.3 B10 1.0 18.0 53.0 25.3 2.7 (comp.) B11 7.0 74.0 19.0 (comp.)
Paraffin Dispersion
[0093] To test the paraffin dispersion, 100 mL of the test oil are heated to 50° C., admixed with the amount of the additive concentrates specified in table 5 (the dosage rates are based on the amount of solvent-free polymer added), and agitated vigorously for 20 seconds. After determining the pour point [Pour point (before)], the oil is heated once again to 50° C. Subsequently, the oil is stored in a 100 mL upright cylinder for 72 hours, at the following temperatures: [0094] test oil 1 at 19° C. (5° C. below the cloud point). [0095] test oil 2 at 6° C. (10° C. below the cloud point) [0096] test oil 3 at 9° C. (5° C. below the cloud point) [0097] test oil 4 at 12° C. (9° C. below the cloud point)
[0098] After the storage test has ended, the upper and lower 50% by volume are assessed visually for presence of turbidity. The quantification of the amount of sediment is based on the total test volume. Subsequently, the upper 50% by volume are cautiously sucked away from the top and the pour point of the upper and lower phases is determined according to ASTM D97 [Pour point (after)], and cloud point according to ISO 3015. A turbid or at least cloudy upper phase and small differences in pour point and/or cloud point in the upper and lower phases show good dispersion. A small amount of sediment indicates weak dispersion and a compact, paraffin-rich sediment.
TABLE-US-00005 TABLE 5 Paraffin dispersion in test oil 1 (storage temperature 19° C.) Pour point Pour point Additive (dosage rate) (before) Visual assessment (after) [° C.] Cloud point [° C.] Example A [ppm] B [ppm] [° C.] upper lower upper lower upper lower ΔCP 1 A1 (500) B1 (125) −6 homogeneously homogeneously −3 −6 21.0 23.5 2.5 turbid turbid 2 A1 (625) B1 (150) −9 homogeneously homogeneously −6 −9 21.8 24.0 2.2 turbid turbid 3 A1 (500) B2 (125) 6 cloudy homogeneously 3 6 17.9 21.2 3.3 turbid 4 A1 (625) B2 (150) 3 homogeneously homogeneously 3 6 18.1 21.1 3.0 turbid turbid 5 A1 (500) B3 (125) 6 homogeneously homogeneously 3 6 20.0 23.2 3.2 turbid turbid 6 A1 (625) B3 (150) 3 homogeneously homogeneously −3 0 20.2 23.1 2.9 turbid turbid 7 A1 (500) B4 (125) 6 cloudy homogeneously 3 6 20.7 24.3 3.6 turbid 8 A1 (625) B4 (150) 0 homogeneously homogeneously −3 3 20.4 23.6 3.2 turbid turbid 9 A1 (625) B5 (150) −6 homogeneously homogeneously 3 6 20.2 23.6 3.4 turbid turbid 10 A1 (625) B6 (150) 3 slightly turbid homogeneously 0 6 20.0 23.8 3.8 turbid 11 A1 (625) B7 (150) 6 cloudy homogeneously 3 9 19.9 23.5 3.6 turbid 12 A6 (625) B1 (150) −6 slightly turbid homogeneously −6 −3 20.8 24.6 3.8 turbid 13 A2 (500) B1 (125) 9 cloudy homogeneously 6 12 19.1 23.8 4.7 turbid 14 A2 (625) B1 (150) 6 cloudy homogeneously 6 9 19.6 23.5 3.9 turbid 15 A3 (500) B1 (125) 6 cloudy homogeneously 3 6 18.0 22.9 4.9 turbid 16 A3 (625) B1 (150) −3 slightly turbid homogeneously −6 0 18.4 22.7 4.3 turbid 17 A4 (625) B1 (150) 3 cloudy homogeneously 0 6 19.0 23.1 4.1 turbid 18 A4 (625) B2 (150) 6 cloudy homogeneously 3 9 18.3 23.5 5.2 turbid 19 (comp.) A1 (500) B8 (125) −3 clear 10% sediment −6 +3 18.1 27.8 9.7 20 (comp.) A1 (625) B8 (150) −3 clear 20% sediment −9 −6 17.5 26.0 8.5 21 (comp.) A1 (500) B9 (125) 15 clear 20% sediment 6 18 17.9 25.0 7.1 22 (comp.) A1 (625) B9 (150) 12 clear 40% sediment 15 12 17.5 25.4 7.9 23 (comp.) A1 (625) B10 (150) 9 clear 20% sediment 12 6 17.8 24.4 6.6 24 (comp.) A1 (625) B11 (150) 12 clear 60% sediment 15 18 18.0 27.1 9.1 25 (comp.) A1 (660) — 15 clear 50% sediment 6 18 17.5 25.4 7.9 26 (comp.) A1 (825) — 12 clear 50% sediment 6 15 17.8 24.4 6.6 27 (comp) — B1 (150) 18 homogeneous; not free-flowing not applicable 28 (comp) — B2 (150) 18 homogeneous; not free-flowing not applicable 29 (comp) — B3 (150) 18 homogeneous; not free-flowing not applicable 30 (comp) — — 21 homogeneous; not free-flowing not applicable (comp.) = comparative measurement, non-inventive
TABLE-US-00006 TABLE 6 Paraffin dispersion in test oil 2 (storage temperature 6° C.) Additive (dosage Pour point Pour point rate) (before) Visual assessment (after) [° C.] Cloud point [° C.] Example A [ppm] B [ppm] [° C.] upper lower upper lower upper lower ΔCP 31 A5 (150) B1 (100) −6 homogeneously homogeneously −6 −6 14.2 15.7 1.5 turbid turbid 32 A5 (150) B3 (100) −6 homogeneously homogeneously −6 −3 14 16 2.0 turbid turbid 33 A5 (150) B5 (100) −3 homogeneously homogeneously −6 0 14.2 15.6 1.4 turbid turbid 34 A5 (150) B6 (100) 0 cloudy homogeneously −3 0 13.8 16 2.2 turbid 35 A2 (150) B1 (100) −6 cloudy homogeneously −6 −3 14.2 16.1 1.9 turbid 36 A2 (150) B2 (100) −3 cloudy homogeneously −6 0 13.9 15.9 2.0 turbid 37 A5 (150) B8 (100) 0 clear 30% sediment −9 3 5.7 16.7 11.0 38 A2 (150) B9 (100) 3 clear 25% sediment −6 6 5.8 17 11.2 39 (comp.) A5 (150) — 0 clear 20% sediment −9 9 6.0 17.4 11.4 40 (comp.) A2 (150) — 3 clear 20% sediment −9 9 5.9 17.8 11.9 41 (comp.) — B1 (100) 9 homogeneous; not free-flowing not applicable 42 (comp.) — B3 (100) 9 homogeneous; not free-flowing not applicable 43 (comp.) — — 12 homogeneous; not free-flowing not applicable (comp.) = comparative measurement, non-inventive
TABLE-US-00007 TABLE 7 Paraffin dispersion in test oil 3 (storage temperature 9° C. Additive (dosage Pour point Pour point rate) (before) Visual assessment (after) [° C.] Cloud point [° C.] Example A [ppm] B [ppm] [° C.] upper lower upper lower lower upper ΔCP 44 A6 (150) B1 (40) −6 homogeneously homogeneously −6 −6 12.1 13.6 1.5 turbid turbid 45 A6 (150) B2 (40) −3 homogeneously homogeneously −6 −3 11.9 13.7 1.8 turbid turbid 46 A6 (150) B4 (40) −3 homogeneously homogeneously −3 0 11.7 13.9 2.2 turbid turbid 47 A6 (150) B6 (40) 0 cloudy homogeneously −3 0 11.5 14.5 3.0 turbid 48 A6 (150) B7 (40) −3 cloudy homogeneously −6 −3 11.4 14.3 2.9 turbid 49 (comp.) A6 (150) B10 (40) 3 clear 35% Sediment −3 9 8.6 16.3 7.7 50 (comp.) A6 (150) B11 (40) 3 clear 30% sediment −3 9 8.9 16.7 7.8 51 (comp.) A6 (150) — 6 clear 20% Sediment −6 12 8.6 16.1 7.5 52 (comp.) — B1 (40) 12 homogeneous; not free-flowing not applicable 53 (comp.) — B6 (40) 12 homogeneous; not free-flowing not applicable 54 (comp.) — — 12 homogeneous; not free-flowing not applicable (comp.) = comparative measurement, non-inventive
Testing of the Filterability of Low-Sulfur Marine Diesel
[0099] To test the influence of additives comprising ethylene copolymer (A) and comb polymer (B) on the filterability of low-sulfur marine diesel, 100 mL of the additized oil were stored in accordance with the conditions described above for the paraffin dispersion (16 h, 5° C. below cloud point) stored. Subsequently, the oil, at the storage temperature, without prior heating, was sucked through a pipette out of the bottom of the measuring cylinder (100 mL) through a paper filter (Ø 4 cm, pore size ≈0.6 μm) at a constant absolute vacuum of 125 mbar. At intervals of 10 seconds, the time that was required for the filtration of the entire sample volume was determined, or, for samples that are difficult to filter, the volume filtered within 5 minutes. The dispersion was assessed here only qualitatively and was assessed as very good (++) when the upper phase was homogeneously turbid, as good (+), when the upper phase was cloudy and the lower phase was without separated sediment, or as poor (−) when the upper phase was clear and a sediment was visible.
TABLE-US-00008 TABLE 8 Filterability of test oil 1 at 19° C. (after storage at 19° C.) Additive (dosage rate) Filtration Example A [ppm] B [ppm] Dispersion t [sec.] Vol. [mL] 55 A1 (500) B1 (125) + 150 100 56 A1 (625) B1 (150) ++ 120 100 57 A1 (625) B2 (150) ++ 130 100 58 A1 (500) B3 (125) + 180 100 59 A1 (625) B3 (150) ++ 150 100 60 A1 (625) B4 (150) ++ 200 100 61 A1 (625) B5 (150) ++ 130 100 62 A3 (625) B1 (150) ++ 200 100 63 A4 (625) B1 (150) ++ 220 100 64 A6 (625) B1 (150) + 240 100 65 (comp.) A1 (625) B8 (150) — 300 50 66 (comp.) A1 (625) B9 (150) — 300 28 67 (comp.) A1 (625) B10 (150) — 300 70 68 (comp.) A1 (625) — — 300 35 69 (comp.) — B1 (150) solid not free-flowing 70 (comp.) — B3 (150) solid not free-flowing 71 (comp.) — — solid not free-flowing
TABLE-US-00009 TABLE 9 Filterability of test oil 2 at 6° C. (after storage at 6° C.) Additive (dosage rate) Filtration Example A [ppm] B [ppm] Dispersion t [sec.] Vol [mL] 72 A5 B1 ++ 110 100 73 A5 B2 ++ 130 100 74 A5 B6 ++ 130 100 75 A5 B7 ++ 120 100 76 (comp.) A5 B8 — 300 70 77 (comp.) A5 B11 — 300 90 78 (comp. A5 — — 300 35 79 (comp.) — B2 solid not free-flowing 80 (comp.) — B6 solid not free-flowing 81 (comp.) — — solid not free-flowing
[0100] In a further test series, the influence of the mixing ratio of components A and B on lowering of pour point, paraffin dispersion and filterability below the cloud point for a low-sulfur marine diesel was examined. For this purpose, a low-sulfur marine diesel (test oil 4) was used, which consisted of the UCOs III and IV and gas oil (II) with the characteristics reproduced in table 10.
TABLE-US-00010 TABLE 10 Characterization of test oil 4 and the underlying components UCO UCO Gas oil Test Method (III) (IV) (II) oil 4 Density @ 20° C. ASTM 0.946 0.937 0.899 0.929 [g/cm.sup.3] D-4052 Viscosity @ ISO 3014 19 6.4 2.2 10.6 40° C. [cSt] Cloud point [° C.] ISO 3015 29.5 11.0 −4.8 20.8 Pour point [° C.] ASTM 27 9 −9 21 D-97 S content [ppm] ISO 14596 154 72 30 93 Proportion in test — 39.6 29.6 30.8 100 oil 4 [% by wt.]
TABLE-US-00011 TABLE 11 Improvement in flowability, dispersion and filterability of test oil 4 at 12° C. (after storage at 12° C.) Additive (dosage rate) Pour Filtration A1 B1 point t Vol. Example [ppm] [ppm] [° C.] Dispersion [sec.] [mL] 82 0 300 15 solid not free-flowing (comp.) 83 30 270 6 + 210 100 84 50 250 3 ++ 190 100 85 75 225 0 ++ 160 100 86 150 150 0 ++ 140 100 87 200 100 −3 ++ 130 100 88 225 75 −3 ++ 120 100 89 250 50 3 + 160 100 90 270 30 6 + 230 100 91 300 0 9 — 300 40 (comp.) 92 0 0 21 solid not free-flowing (comp.)
[0101] The experiments show that additives comprising ethylene copolymers (A) and comb polymers (B) lead to good dispersion in wide mixing ratios, and the low-sulfur marine diesels additized therewith are filterable without difficulty. Additization with noninventive additives, by contrast, leads to marked sedimentation of the paraffins and to rapid filter blockage. While ethylene copolymers (A) on their own, and also combinations with noninventive comb polymers, lead to lowering of the pour point, only in combination with comb polymers (B) of the invention are good dispersion and filterability achieved. Comb polymers (B) on their own bring about only marginal lowering of the pour point, and so the samples solidify at storage temperatures below the pour point. In oils additized in this way, there is no sedimentation of paraffins, but they are not pumpable either. For this reason, separation and separate examination of upper and lower phase cannot be conducted in a comparable manner.
[0102] In further comparative experiments, a dark-colored bunker oil comprising residues from mineral oil distillation and having 2.9% by weight of sulfur was examined with regard to the influence of the additives of the invention on lowering of the pour point and on the influencing of paraffin dispersion and filterability by the test methods described above for low-sulfur marine diesel. Because of the low transparency of the bunker oil, the paraffin dispersion was assessed by determining the wax appearance temperature (by means of differential scanning calorimetry, DSC).
[0103] Further characteristics of the bunker oil used were a density (at 20° C.) of 0.995 g/cm.sup.3, a viscosity (at 40° C.) of 280 cSt, a pour point of 33° C. and a wax appearance temperature (corresponding to the cloud point, which cannot be determined in oils comprising residues) of 47° C.
TABLE-US-00012 TABLE 12 Improvement of flowability, dispersion and filterability of a bunker oil with 2.9% sulfur at 30° C. (after storage at 30° C.) Additive (dosage rate) Pour Dispersion Filtration A1 B1 point WAT WAT t Vol. Example [ppm] [ppm] [° C.] (upper) (lower) [sec.] [mL] 93 500 125 30 47° C. 47° C. 300 <10 (comp.) 94 1000 250 27 47° C. 47° C. 300 <10 (comp.) 95 0 0 33 47° C. 47° C. 300 <10 (comp.)
[0104] Comparative experiments 93 to 95 show that the phenomenon of paraffin sedimentation which is observed in low-sulfur marine diesel does not occur in conventional sulfur-rich bunker oil, and that filtration through fine filters is not possible.