CA2128020C - Additives and fuel compositions - Google Patents

Abstract

An additive composition for improving the cold flow properties of crude oils or fuel oils such as middle distillate Eras! oils comprises an addition product or condensate cold flow improver additive in combination with a demulsifier.

Description

i v~ ~"? S'!. 't :o 1%VU 93/1417~t E:: .~_ ~,. ..', ':' :.~ ;.? PCT/EP93/000~31 additives arid Fu~l ~~rnp~sa~ic~n~
This invention relates to the use of additives for improving the cold flow properties of crude oil or fuel oil, for example distillate petroleum fuel such as middle distillate fuel oil boiling within the range of 110°C to 500°C.
When oils and fuel oils are subjected to low ambient temperatures, wax may separate out from the fuel arid impair the flow properties of the oil. For example, middle distillate fuels contain wax which precipitat~s at icw tempdratures to form 9 0 large waxy crystals which tend to plug the small pore openings of fuel filters.
This problem is particularly acaate when the fuel is a diesel fuel because the nominal apertures in the fuel filter of diesel engines are typically of diameter between about 5 and 50 microns. Additives are known in the art for overcoming the above problem and are called Flow Improvers.
Such additives may act as wax crystal modifiers when blended with waxy mineral oil by modifying the shape and size of crystals of the wax therein and reducing the adhesive forces between the crystals and between the wax and the oil to permit the oil to remain fluid at a lower ts:mperature than in the absence ~f ~o the additive.
Many additives are desctib~d in the art for improving the cold-flow properties of oils, fbr example in the form of oil-soluble addition pr~du~ts or condensates that mad be polymeric or mbnomeric and as described, for example, in 25 US-A-3,046,470; ~JK-A-~ ,263,9 5~; 1~5-A-3;96 ,96~ ; and EF'-A-0;~6~ ,957:
Soiir~e ~f the above additives have been and are used comrnerciaily as Coid Flow lmprovers. However, there is a reed to improve p~rfor~nanc~, particularly over a range of oils.
so tJS-A-3;B50,5r37 describes fuel c~e~positic~ns c~mprising a middle distillate fuel and a flow improver composition comprising a hydroc~rbyl succinic acid or amine salt thereof, an ethylenewinyl acetate polymer ana, optionally, an aromatic monocarboxylic acid: Other additives ai'e described as c~ptionalty being present, one type beirog a d~m~alsifier: hfowwer, the demulsifier~ are not 35 described as having fl~w irhprover pro~aerties.

wca ~~m~~H ~~riEP~3iooos~
.,.; :,.;~~s ~~ ,~. ;:.' ;. ~ J a? J

fn this invention, it has surprisingly been found that demulsifiers may improve the cold flow properties of oils and also may art synergistically in providing such properties when used in combination with addition products or condensates that themselves have cold flow improving properties. Also, the proportions of demulsifier that are used may be surprisingly small.
A first aspect of the invention is an additive composition comprising:
(i) one or more non-metallic flow improving oil solubl~ addition praducts or 9 o cor~densates capable of improving, either jointly or singly, one or more cold flow properties of a crude oil or fuel oifo and (ii) a non-m~tallic oil soluble demulsifier, provided that th~ compon~nt (i) is not a combination of a substituted succinic acid der9vative and an ethylene-vinyl acetate copolymer.
The composition may be in admixture with a major proportion of ~ crude oil or a fuel oil, the composition constituting a minor p~~oportion. Further, the composition may be dispersed in a liquid medium compatible with a crude oil or a fuel to form ~o o concentrate.
A second aspect of the invention is the ease of an additive domposition of the first aspect of the invention for improving the cold flow prc~pertios ~f a crude oil or a fuel oil.
The examples hereinafter shovel that a deinulsitier used in combination vuith the addition pr~ducts andlor the cor~densates gives rise to unexpected impr~verttents in the.~ld flow propertied of ~ils.
3o The features of the invention will now be discussed in further detail.
~E~~L,.~iFI~R
in this specification, a dernc~lsifier is a material thaf oan caus~ an oil-water s5 emulsion to break down to form discrete; separable oil and water phases, he ail being a crude oil oc fuel t~i~ of the ir~~ention9 for example at a concentration of Q.1 to 2,800 ppm by weight based on the weight of the fuel. It requires a balance .. : ~ ;'a ; ~, : a ,., G.; .:. '." : ~i ~~..' ' .: ~,i rv~ ~~iy~ay~rH ~ Pcri~p~3iooo~, _3_ between hydrophilic and hydrophobic properties. Thus, it must be sufficiently hydrophobic to dissolve in the oil of an oil/water emulsion to break the emulsion, and must be sufficiently hydrophilic to prefer the aqueous phase which separates from the oil phase after the emulsion breaks.
The demuisifier may be a surfactant that alters the surface or interfacial tension of the droplets in the disperse phase ofi the emulsion to make them unstable, e.g.
by raising the surface or interfacial energy.
y o The demulsifiiers used in this invention have a hydrophilic part and a hydrophobic part. They may, for example, be divided into two groups as follows:
~r~rrap 1 is a condonsate comprising a hydrophobic part and orte or more oxyalkylated groups comprising the hydrophilic part.
The hydrophobic part is derived from a precursor having one or more groups such as hydroxy groups; amino groups, i.e. primary, secondary, tertiary and quaternary ammonium groups; and ha6ogen c,~roups capable of a condensation reaction to form the oxyalkylated groups.
~o The oxyalkylated group may, for examp9e, have up to 50 oxyalkyl units per group capable of a condensation reaction; and each such oxyaikylated unit may, for ' example, have from 2 to 6 carbon atoms and may for example be ethoxy, prapdxy, or butoxy. The oxyaikylated units in a particular oxyalkylated group 25 r~nay be the same or different.
~ne example of demulsifiier within C~r~up 1 is d phenolic resin of the gerDeral formula below, being a precursor for the hydr~phobic part, the hydrbxy groups of which have been condensed to form oxyalkylated groups:
so r>

WO 9:~/1~1178 PCT/lrl'93/OOOH1 a .> ''~ ~ ~~ ';3 : '~
. . '~'.~:-~ it where R represents an aliphatic hydrocarbyl group having firom 3 to 24 carbon atoms such as 9 or 15, and n represents an integer from 1 to 20 such as 4 to 10.
The hydrocarbyi group contains C and H atoms and is bonded to the rest of the molecule by a carbon atom. 1t may be straight chain or branched, be saturated or unsaturated, or be~ alicyclic and may contain one or more hetero atoms (e.g.
O, S, N) provided that such hetero atoms do not substantially ahter the hydrocarbyl nature of the group. Preferably, R is an alley! group.
Such phenolic resins may be made by the base catalysed oxyalkylation of an 1 o alkyl phenol-formaldehyde resin made by acid catalysis. They are described in, for example, US-A-2,499,367; US-A-3,424,565; and US-A-3,?5~2,657.
The number average molecular weight of such oxyalkylated phenolic resins as measured by Gel Permeation ~hrort~atography (t~PC) may, for example, be up to 200,000, such as up to 150,000, preferably up to 50,000, more preferably up to 25,000, even more preferably up to 10,000.
Another example of demulsifier within Caroup 1 is a linear mono or polyhydroxy compound, being a precursor for the hydrophobic pert, the hydroxy groups) of 20 which has or have been condensed to form oxyalkylated groups.
Such linear compounds may be mono or polyhydroxy alcohols such as m~no or poiyalkyiene glycols, e.g. where the alkylene groups have from 1 to 6 carbon atpms, or pentaerythritol~ or mono or p~lycarboxylic acids sr~ch as aliphatic fatty 2~ acids or adipic acid.
' A~aother example of demul~ifiier witB~in Croup 1 is a diglycidyl ether the epoxide groups ~f which being ring opened with a hydrbxy moiety; e:g. ~
p~lyoxyalkyl~ne such as polyethylene glycol or potypropyB~ne giyc~l to geraer~te; in ~dditiorx t~
so the oxyaBkyl groups, hydroxy groups whidh themselves can optionally be o~yaikylated to form a branched or cross-linked dsmulsifisr.
Another exar~pBe of demulsifier within Group 1 is an oxyalkylated amine (Primary; secondary, tertiary or quaternary) ~nalagous to the above-mentioned oxyalkyl~tad hydroxy compcaunds, and a~x~alkyBated fatty amines reacted with adipiG acld.
~xampies of demulsifiers are also described in US-,~-4,$36,629.

f1 ;'. ~~.! ...
Wta 9:~/I~1178 i,; ~ ~,. ~.:- i.~ ... '~y PC'I'/EP93/OU081 Group ~ is a compound having a suiphonate or suiphonic acid group as the hydr ophilic part, attached to a hydrophobic part which may, for example, be a long chain alkyl group. Specific examples are alkyl aryl sulphonates.
The demulsifiers used in this invention may also be characterised by their relative solubility numbers, referred to herein as RSN. The RSN can be correlated to the hydrolipophilic balance (HL.B), typically between 8 and t 1 for demulsifiers. RSN is determined by dissolving 1 g of the cfemulsifier in 50 ml of acetone and titrating distilled water into the solution until a pem~anent haze ~ o occurs. The number of mls of water added is the RSN. The RSN range of the demuisifiers used in this invention is suitably from about 4 to about 25, preferably to about 20.
Examples of demulsifiers that may be used in this invention are ethylene ~ 5 oxide/propylene oxide copolymers; p-alkylphenolformaldehyde resins of such copolymers and modifications thereof; polyester amines; amineoxyalkylates;
oxyalkylates; cyclic-p-alkylphenolformald~hyde resins and comp)ex modifications thereof; cross-linked polyols such as polyol esters, polymeric esters and resins, chain exfended polyols, oxyalkylated chain extended polyols, 2o alkoxylated fatty acids, and heteropolyols; amines such as oxyaikylated amines (e.g. ethoxylated armihes) and polyester amines; dxyalkylated phenol-formaldehyde resins; sulphonates; sul~hosucoinic acid esters; oxyaikylated phenols; poly-alphaohafins9 end blocked polyols. The above specified der~ul~ifi~rs are not necessarily mutually exclusive.
~5 The demulsifie~s may be used in this inventibn singly or as mixtures of snore than one demuisifier.
A~t~1'T~C~BV ~Ri~DII~"1'~ ~R t;~td~ENa~'TE~
'the addition products are formed by an addition reaction as such and tho condensates by a condensation reaction comprising addition ~f one moledule to another with the elimination of a simple molecule such as water, ammonia or an alcohol. They include maf~riais that are kn~~vn in the art for improving he cold s~ flow properties of ~ils. Bh this specification, reference $o such prbdu~ts and conderisates includes products and conclensates that hav~ bean made by a pr~cess sequence including an addition or cohdensation reaction, for example W() 93/ 14178 ; ~ .' : , ~ ~ ' ;~ 4' j PC d~/EP93/000~31 G.: ..:. .. '..~~ ~.~ ..J ~J

an addition product or condensate that has been subjected to one or more subsequent pracessing steps.
Examples of addition products are one or more copolymers ofi ethylene and an unsaturated monomer ofi the general fiormula ~~
wherein R6 is hydrogen or methyl, R~ is a -~~GR8 group o wh~rein R8 is a hydrogen fiormate or a C1 to Cz$, more usually Ci to ~C~7, and prefe~~ably a C~ to C8, straight or branched chain alkyl group; or R~ is a -C~t3R~
group wherein R$ is as previously described but is not hydrogen and I=i~ is hydrogen or -CCOR8 as previously defined, and may include other 1 s oomonomer(s) to give rise to, fior exemplar, ter~~olymers or tetrapolymers or higher, fior example where the other comonomer is an iso-oiefiin suarh as di-isbbtytylene or isobutylene.
The Monomer, when R6 and R~ are hydrogen and R~ is -~~CFds, includes vinyl zo alcohol esters ofi C9 to Czs; moray usually C9 to C5, mono-carboxylic acid, and preferably Cz to C2~, more usually C~ to C5 mort~-carboxylic did, and preferably Cz to C5 ~na~no-carbo~y46c acid. Examples ~f vinyl esters which may be copofymeris~d with ethylene include vin~rl aoet~te, vinyl ~ropia~nata~ and vinyl butyrate or is~butyrate, vinyl aa~~tate being preferred. It is prefierrad that these '5 copolymers have a number average molecular weight as measbred by vapoctr phase os~metr~r ofi 1,000 to 1 x,000, ~referabiy 1,000 to b;000.
Examples of condens~~es are as fcaiinws.
so An oil-soluble polar nitrogaan compound comprising one or more ~f the compounds (i) to (iii):
(i) an amine s~iit andlor amide torrraed by ra~~tir~g at least ~ne molar proporii~n of a hyd~osrarbyi substituted amine with a molar proportibn ~f a (;) ~ :,"a .l s~~ i~ ~'H
'~'V() ~Ja/1~17H i'~ .. :'.~~ ~~; ;~ ~:r to PCI'/EIy93/00081 _7_ hydrocarbyi acid having 1 to 4 carboxylic acid groups or their anhydrides, or a condensate such as described in EP-A-327,423;
(ii) a chemical compound comprising or including a cyclic ring systerr~, the compound carrying at least t~nro substitusnts of the general formula (!) below on the ring system (') where A is an aliphatic hydroc~rbyl group that is optionally interrupted by one or more hetero atoms and that is straight chain or branched, and I~' and R~ arer the same or different and each is independently a hydrocarbyl group containing 9 to 4~ carbon atones optionally interrupted by on~ or more hetero atoms, the ~iabstituents being the same or different and the compound optianally being in the form of a salt thereof; and (iii) a condensers of ~ long chain primary or secondary amine with a carboxylic acid containing polymer, for example as described in C"aB-A-2,121,807, FF~-Aa2,592,367 and L)E-A-3,941,569 .
9n (i), (ii) and (iii) ab~ve, the f~ii~wing is t~ be hated.
(i) Ester/amides may b~ used ~~ntaining 3Q t~ 3~~, prefierab8y 50 to ~ 50~
tote!
carbon atoms. '1'h~~e r~itrpgen c~srapo~nds are described in U~ Patent 2s ~ 211 534. suitable arnin~~ ire usually long c~~in ~t~-~~o primary, secondary; tertiaa'y or qua$ernary amine or mixtures there~f: but sh~rter chin amines r~~~ be used provitibd the res~rlting bitrogen dfamp~und i~~
~ii soluble end th~r~firar~ r~~rrrsall~ containing about 30 t~ 300 total ~arbd atoms. The nitrogen ~~~apound iareferably c~ntains at !dear one straight ~o chain C$ to C,~o; preferably ~1~, to C~;~ alky9 segment.
auitable amines include prirry~ry, secondary; terti~cy or quaternary; bat preferably are sdcondary. Tdrti~ay and quat~rnary amines cap ~niy f~rrrt mine salts. Exaimp6es of arnine~' incidde tetradbcyl amine, ,~~o~min~;
~5 and hydrc~~~nated tallow arming. Exarx~ples bf se~nddry ai~rines include diractacedyl amir~~ and rnethy!-beharsy~. Arnii~e mi'ctures are also ~uitab9e such as those derived from nat~rai materials. A preferred arr~ine is a ~v~a ia3mauH w~ri~~~~~iooos~
~ t ~ ;'; r, ~ : j ~
t,: .:. ('~~ v ~-( .' w ~~~
secondary hydrogenated tallow amine of the formula HNR~F~2 where in R~ and R~ are alkyl groups derived from hydrogenated tallow fat composed of approximately ~°/a C~ ~, 31 % G~ s, 59% C18.
Examples of suitable carboxylic acids and their anhydrides for preparing the nitrogen compounds include cyclohexane, 1,2 dicarboxyiic acid, cyciohexene '! ,2 dicarboxylic acid, cyciopentane 1,2 dicarboxyiic acid, ethylene diamine tetracarboxylic acid, naphthalene dicarboxyiic acid and the like. Generally, these acids have about 5-13 carbon atoms in the cyclic moiety. Preferred acids useful in the present invention are benzene dicarboxyiic acids such as phthaiic acid, isophthaiic acid, and terephthaiic acid. Phthalic acid or its anhydride is particularly preferred. 'The particularly preferred compound is the amide-amirfe salt formed by reacting 1 molar portion of phthalic anhydride with 2 moi~ar portions of ~ 5 dihydrogenated tallow amine. Another preferred compound is the diamide formed by dehydrating this amide-amine salt.
(ii) Preferably, A has from 1 tai 20 carbon atoms and is preferably a methylene or polymethylene group.
"Hydroparbyin rreeans an organic moiety composed of hydrogen arid carbon bonded to thd remainder of the mo9ecuie by a carbon atom ewhich, unless the context states othe~vise, may be aliphatic; including aiic~rciid;
aromatic; or any c~rrbbination thereof. It may be substituted ~r unsubstituted alkyl; aryl br aralkyl and rraay option~9ly contain unsaturation. Examples where it is substituted ire oxy-9 halogena- and ' hydroxy-hydrbcarbyi.
The cyclic ring system may include homocyclic; heterocyciic, ~r fused 3o poiycydlic assenlbiies, or a system where two or mare such cyanic assernbiies are jpined tb one an~ther and irk which the cyclic assemblies may be the sarn~ ~r ditfer~nt~ ~Vh~re them are two ur more siadh c~~iic assemblies, the substitubryts bf the general formula (i) may bb ~r~ the same or ~iiff~renf assemblies, preferably on the same as~ambly:
s5 Preferably, the or each cyclid assembly is ~romatib; more prefiarably benzene ring. Most prefarabl~, the cyclic ring system is a single beh~e~e rdc~ ~:~i ~ a a 7s ,, .; ;., ~~, :.~ ,, YCT/lE;P93/00081 ~ .: 1J
ring v~rhen it is preferred that the substituents are in the ortho or mete positions, which benzene ring rnay be optionally further substituted.
The ring atoms in the cyclic assembly or assemblies are preferably carbon atoms but may for example include one or more ring ~!, S or ~
atom, in 'nrhich case or cases the compound is a hetarocyclic compound.
Examples of such polycyciic assemblies include o (a) condensed benzene structures such as naphthalene, anthracene, phenanthrene, and pyrene;
(b) condensed ring structures wher~ none of or not all of the rings are benzene such as azulene, indene, hydroindene, fluorene, and 1 s diphenylene oxide;
(c) rings joined "end-on" such as diphenyi;
(d) heterocyclic compounds such as quinoline, indole, 2:3 2o dihydroindole; benzofuran, coumarin, isocoumbrin, benzothiophen, carbazole and thiodiphenyiamin~e;
~ (e) non-aromatic or partially saturated ring sy~terns such as decali~a (i.e. d~cahydrondphth~lene), a-pinene, pardiner~e, and bornylene;
2~ and (f) three-dimensional structures such as norbornene~ bicy~l~heptbne (i.e. norborndne); bicycldo~ar~e, and bicycl~octen~.
so Eabh hydrocarbyi group constituting R~ and R2 in the invention may f~r example bo an alkyl or alkylen~ group or a mono- or poly-alko~cya9ky!
group. Freferabi~; each hydroc~rbyl gr~up' is a straight chain alkyl group.
The number of carbon ate~rns in each hydr~carby! gr~up is preferably l6 to 40, more pref~r~bly 16 to 24.
Also, it is preferred that the cyolic system is substituted with tw~ only substit~ents of the general formula (!) and that A is a methylene group, i~t> 9:3/1417t~ PCI'/EP93/d1d108!
a ~ ~v f 1 w , 7 , i W
~ i ' .,, ;~ _ 1p LJ .. : ., ',. './ ..
Examples of salts of the chemical compounds are the acetate and the hydrochloride.
The compounds may conveniently be made by reducing the corresponding amide which may be made by reacting a secondary amine with the appropriate acid chloride.
(iii) Esters of telomer acid and aikanoloamines such as described in US-A-4,C09,~56; the reaction product of an amine containing branched 1 o carboxylic acid ester, an epoxide and a mono-carboxylic acid polyester such as described In US-A-4,6~1,07i .
Further examples of condensates ar~ the f~ilowing9 which are co-additives for improving the cold flour properties of distillate fuels. Examples of such co-additives are as follows:
~~~aka Polymers Such polymers are discussed in "Comb-Like Polymers. Structure and 2o Properties", N A Plate and V P Stlibaev, J. Poly. Sci. fVlacrornolecular Revs., 6, p 117 to X63 (1974).
. Advantageously, the comb polymer is a horrlopoiymer having, or a copolymer ai least 25-and preferably ~t least 40; m~re preferably at least 50, molar per cent of the units of v~hich have; side chains c~ntaining at least fi, and preferably at least 10, atoms, Examples are those having the general formula ~ H J t~l a ~ ~
,Cep Cr.,C_ ~ ~ a~ ~ ~ t- n where !~ .- R, CO.~JR, OC~:R, f~~CO.~R or ~R
E - H or CHI or p or F~1 G - Vii, or D

wca ~m r a r ~~ ~'~ .s~~ .':~ '~ ~ ~' ;_r~c rmP9moooH r m _ 1.0 (homopoiymer~ to 0.4 (mole ratio}
J - H, R~, Aryl or Heterocyclic group, or F3~CO.OR
K _ H, CO.OR1, OCO.FtI, OR1 or C02H
L - H, F3~, CO.~R~, OCO.R?, P.ryl or C02H
n - 0.0 to 0.0 (rraole ratio) Coo f~f > C~
Another rnonorner nay be terpolymerized if necessary.
1~
Examples of suitable comb polymers are fumaratefvinyl acetate copolymers, particularly those de scribed in European Patent Applications Ot5~~976 and 01 ~~'iT7; est~rified oiefinlrr~aleic are6~ydr'sds c~polyrners; pbiymers and copolym~rs of alpha of~finlr~aieic anhydride c~pofymers; polymers and copolymers of alpha olefins; ~esterified copolymers of styr~ne and malefic anhydride or fumaric acid; and polynners of alkyl esters of ita~nic acid or citraconic acid such as th~se r~here the aik~! ciroups hare from ~ 0 to 1 ~
carbon atoms and the polymer has a number a~drage~ molecular Freight of from 1,000 to 20,Q00.
2~
~~vy~~y~~~y~~n~ co~~~urla~
Examples ore poiyoxyeikylehe esters; ethers; ~st~r/ethers and mixtdre~
thereof, particularly ;those coratainir~g at toast one, preferably at least two C1 p to O~p linear s~turaged alBtyl groups end ~ polyoxyalkylen~ glycol group of nnoiecufar ~rreight 3 OO to b,000 preferably 200 t~ b000, the alkyl group in said p~lyoxy~lkylen~ glycol containing frorr~ 'i to 4 carboy atoms. These mat~ridls fcirm the subject of Eurbpean Patent F'ublicati~n 0 069 0~~ A2: Other such additives ~re~ describod in lJnited Mates Patent 4 491 455.
'The preferred'est~rs, ethers or ester/ethers rr~hieh may be used cmay be strtacturaliy depicted by the forrnuia s~~~~
v~here f~ and ~t2 are the same or different and rnay be ~O t)3/ 14178 PC'~'/EP93/0~08i ,!
.. ..; ;:>
(a) n-alley!
O
(b) n-alkyl-C
C) 1e (o) n-alkyl-U-C-(CHOW
O O
Ii !i (d) n-alkyl-t~-C-(CH2)yG--the alkyl group being linear and saturated and containing 1 a to 30 carbon 9 O atoms, and A r~presents the polyalkylene segment of the glycol in rrvhich the alkyfene group has 1 to 4 carbon Moms, such as polyoxyn~ethylene, polyoxyethylene or polyoxytrimethylene rvoiety which is substantially linear;
some degree of branching with lower alkyl side chains (such as in polyo~ypropylene glycol) may be tolerated bl,t it is pr~f~rred thafi the glyc~I
1 s should be substantially linear. A rnay also contain nitrogen.
suitable glycols ~cner~lly are substantially linear polyethy9~ne glycols (~~t,~) and p~fypr~pyhne glycols (PPG) havihg a ~aol~cular vveigh~'of about 100 to ~,~00, prbferabl~r about X00 to 2,000: asters are preferred and fatty acids 20 ~ c~tataining from 1 ~D-30 c~xrboh atoms are useful f~r reacting ea~ith the gly~l~ to form the esier aciditi~es; it berg preferred t~ use a Cys-G~4 fatty adid, esppdi~lly behenic acid. The esters may also be .prepared by esteriflying p!~ly~thoxylated fatty kids or pc~lyethoxyiated al~hnls.
25 f'~aly~xyalkyler~e diesters, diethers; eth~r/esters and rniactures tner~~~
are suitable as edditive~, die~~ers being Pref~rr~d for use in narrow boiling diiilatt~s when minor annount~ of monoethers and monc~ester~ (which are often formed 'so the ~rronufacturirig process) may also b~ preserve. It is important for additive perlomaance that ~ major ~m~unt of the dialkyl compound is present: In so particular, ~t~aric'~r beh~ni~c diesters ~f polyethylene glycol;
p~lypr~pyie~e glycol or polye~hylene/polypr~pylane glycol mixtures are pref~rred.~

,'1 ~-. ,.1 ~:.: .' ~: ; ~.~ ;.f l; P~Cf/EP9~/OUOfDD
W(? r~?3/ 14178 -'13-Examples of other compounds in this general category are those described in Japanese Patent Publication Nos 2-51477 and 3-34790 (Sanyo), and EP-A-~ 17,~ 03 and EP-A-326,356 (NOF).
Hydrc~carbc~n P~ly~ers Examples are those represented 'by the folloinring general formula .
T H !J H
I l I I
~-G
°3' T v ~ ~i U y~
where T - H or Fi1 U ~ H, T or Aryl - 1.0 to 0.0 (mole ratio) w -. 0.0 to ~ .0 (mole ratio) where Ft1 is alkyl.
These polymers may be made directly from ethylenically unsaturated monomers or indir~ctiy by hydrogenating the polymer made from monomers such as _ ispprene, butadiene etc.
A particularly preferred hydr~carbdn poiyrner is a c~poiyr~~r of ethylene and propylene haying an ethylene content preferably between 20 and sOp/o (~r/w) and is cor~-imoniy made via homogeneous catalysts.
zs sulphur Car~~xy Comp~unds Examples are those described in EP-A-0261357 which describes the i~se ofi compounds of the genera! formuh so ~~C/o~~~
C

w~~ mi~Il7~ hCTm~~3ioooH~
,, ; ~ r~ f~ ~~ ~'~
P:. .: . 1,i ;.~ , . ~l in which -Y-R2 is S03~r(+>NR3R2, -503->(+)HNRzR2, -S~3(-)(+)H2NR3[~2, -S03(-)t-f-)H3NR2~
-SO~NR3R2 c~f -S~3R2;
-X-R1 is -Y-R2 or -CONR~R1, -CO2(-)(+)NR3R1, -COZ(-)(+)HNR2R1, -R4-(~~OR1, °NR3COR1, -R'~R1, -R4l~C~R1, -R~,R1, -N(C~R~)R1 Or z~-)t+)NR3R1;
-Z(°) is S~3i') Or -COZ('i;
R1 and R~ are alkyl, alkoxy alkyl ~or polyalkoxy alkyl containing at least 1 ~
carbon atoms in the main Ghain;
R3 is hydrocarbyi and eaoh R~ may be the earns or different and R~ is' nothing or is C1 to C5 aikylene and in ~\
C
/C
the carbon-carbon (C-C, bond is 'either a) ethylenically unsaturated when A
and B r~nay be alkyl, alkenyl or substituted hydrocarbyi groups or b) pert of a cyolio structure vrhidh may be aromatic, polyraucl~ar aromatic or c~clo-ali~ahatic, it is preferred that X-R1 end Y=R~ b~t~veero them contain at least three alkyl, ' aikoxyalkyl or polyalkoxyalkyl group:
~Ifulticomponent additive systems Pray be used and the ratios of additives to b~
used will depend on the fuel to be treated.
3o C)IL
The oil may be a crude oil; i.e: ~i! obtained diredtiy from drilling and before refining; th~ compouhds. of this inv~ntior~ being suitable fer use as flog imps~vers or de~axing aids therein.

W~ 9.'i/I~i178 'x °; '~ ,°, :, .~, n P('1'/EP~31000~i F.,. . _. , . .. t y l ,. ~.i The oil may be fuel oil suitably a middle distillate fuel oil. Such distillate fuel oils generally boil within 'the range of about 110°C to about 500°C, e.g. 7 50° to about 400°C. The fuel oil can comprise atmospheric distillate or vacuum distilPate, or cracked gas oil or a blend in any proportion of straight run and thermally andlor s catalytically cracked distillates. The most common petroleum distillate fuels are kerosene, jet fuels, diesel fuels, heating oils and heavy fuel oils. The heating oil may be a straight atmospheric distillate, or it may contain minor amounts, e.g. up to 35 wt%, of vacuum gas oil or cracked gas ails or of both.
The fuel ail may be an animal, vegetable or mineral oil and may also be synthetic. It may alas contain other additives such as stabilisers, dispersants, antioxidants and corrosion inhibitors. Also, thp fuel oil may have a sulphur concentration of 0.2% by weight'or less based on the weight of the fuel, preferably 0.05% ar less, mare preferably 0.01 % ar less.
The concentration of the demulsifier in the oil ~maY far example be up to 2,000 ppm of additive (active ingredients by weight per weight of fuel, but preferably not greater than 50 ppm when used in combination with other additives, with a preferred lower limit of 5 ppm. The concentreti~n of such other 20 ~dditlves may be 10 to 2000 ppm (active ingrbdient) by weight per t~reight of fuel, pref~rabfy 25 to 500 ppm, more preferably 100 to 200 fpm. If used on its own, the demulsifier may nave a concentration of up to 1000 ppm by weight, . preferably up to 500 ppm, more preferably up to 300 ppm.
z5 ~ The additive or additives should be soluble the oil to the extent of at least 1000 ppm by weight per weight of ail at ambient temperature. However, at leapt same of the additive may come out of solution near the aloud point ~~ the oil in order to modify the wax crystals that form.
30 ~~hICEI~~"I~AT~
The concentrates of the present invention are convenient as a means for incorporating the additive into' bulk oil such as di~tilfate fuel, which incorporation may be done by methods known in the art. The coneentr~tes may alas contain other additives as required a0d preferably contain from 3 to 75 wt%, mire preferably 3 to 60 wt%, most preferably 10 to 50 wt% of the additives preferably in solution in oil. Examples of carrier liquid are organic solvents including ~U ~:3i ~ as 7s ~cri~p~3ioooH ~
'' ~ '. ';!;
. . . '..~ : .. ~. ~ _ hydrocarbon solvents, for example petroleum fractions such as naphtha, kerosene and heater oil; aromatic hydrocarbons containing aromatic fractions (e.g. ~olvesso (trade name)); and parafifiinic hydrocarbons such as hexane, pentane and isoparaffins, and includes mixtures of the above. The carrier liquid must, ofi course, be selected having regard to its compatibility with the additive and with the fuel.
The additives of the invention may be incorporated into bulk oil by other methods such as those known in the art. Ifi co-additives are required, they may be ~ o incorporated into the bulk oil at the same time as the additives of the invention or at a different time.
~~~4MP~~~
The invention will now be particularly described by way of example only, as fiollows.
AI3~1'rllJ~~
2o The ~oliowing additives were used and will be referred to under their designated numbers:
1. ~ernuisiifiers 1: a linear adipate made by esterification of adipie acid with polypropylene glycol under acidic conditions to give an adipat~
ester.
2: a product made by oxyalkylating dipropylene glycol under basic conditions to give an intermediate product which is reacted with a diglycidyl ether epoxy resin.

3: an oxyalkylated pofyether resin made by oxyaikylating dipropyiene glycol under basic conditions to give an intermediate product similar to that ~btained in preparing ~emulsifier 2, which product is reacted with a diglycidyl ethbr epoxy resin to give a pr~duct which is further oxyalkylated with propylene oxide.

rll :") .,v iu -. , .. '.I .: :i wt~ ~~i o a i ~t~ ~~rmP93iooos ~
2. Other l~dditives 4: an ethylene-vinyl acetate copolymer of number average molecular weight 5000 as measured by GPC (Gel Permeation Chromatography) and containing 13.5% by weight of vinyl acetate.

5: an ethylene-vinyl acetate copolymer of number average molecular weight 3300 as measured by f~PC and containing 36°,/° by weight of vinyl acetate.
~o 6: a hJ,N-~diaikylammonium salt of 2-N~,Nj_diaikyi-amidobenzoate being the reaction product of reacting one r~oie of phthali~
anhydride with t"avo m~les of dehydrogenated tallow amine to form a half amidelhaif amine salt.
an itaconate polymer of number' average molecular weight about X000 as measured by GPC prepared by~ polymerising a mbnoryaer ire cyclohexane solvent using a lfree radical catalyst, the monomer containing linear alkyl groups of 13 curb~n atorr~s.
a copoiyrr~er of styrene and e~t~rifi~d f~rmari~ acid ~nrher~in the eilkyt groups have 14 barbon a2br~n~, ~h~ cop~lym~r having a' number average rnolecuiar weight of ~f ~Q00 as measured by C~~C and prbportions of ~tyrone and esterified fumaric acid in the ratio of 1:1 (moie:moie).
g: a demuisifier coexisting of oh alkylated phenol-forinald~hyde resin condensate made by tie abed csit~iysed condensation ~f a C
dikylated phenol kith formaldehyde f~fl~wed' by oxyalk~latir~g under basis cohditions with ethylene oxide.
10: an eti~ylen~-vinyl acetate ~~pofynner of number averb~e mol~cuiar weight of 3;300 a~ measured by GPC and c~ntaining 2g% b~
weight of vinyl ad~tate 'WO ~~/ I ~t 1 "~~i PC'1'/EP93/OOOR 1 ..; :~~ ~ 1 l;., .~. . ~. ~ ' , :. r - 18 -FUlrLS
The following fuels were used:
Fuel IiVAT (C) density ~-86 Distafiatson (C) -(gems) so-2o ~~~-so a o.8 o.83s8 1 ~8 30 -o.2 0.8.00 91 30 y~a~ (a$ ~~6 D~still~tion (C) ~ Cao~~ ~~i~~

m~ ~~% s~~io Cloud Point) (C) C 2.0 -3 1 i'4 233 3~.3 3fi9 KEY: 1IVAT is Wax Appearance Temperature as measured by Differential Scanning Calorimetry (C?SC).
ASTIVI D-86:
~ 0 90-20 is the difference between the temperatures at which 90 and 20%
of the fuel (by ~olurr~e) hid distilled.
F~~-90 is the difference between the final boiling point of the fuel and the temperature at which 90°l~ of the fuel (ay ~oolume) has distilled.
FOP; i~~ are final end initial boiling points.
9 5 C~' as measured by iP 219/82.
°f STS
Additives were dissolved in tire fuels and the following tests performed on 2o untreated fuel and on fuel treated with additives to rneasur~ the following in order to assess the effectiveness of the additives tested as'filterabilaty improver in distillate fuels.
Cold Pilfer Pluggirsg Point (CPPP) The test ~ra~ carried out by the procedure described in detail in "Journal c~~
the Institute of Petroleum", l/oldme 52; Number 5109 June 1986, pp. 1 ~3-285. This .

W(? 9:i/ 14178 PC~1'/E~'93/U0081 test was designed to correlate with the cold flow of a middle distillate fuel oil in automotive diesel engines.
Sirl~ulated Filter Plugging Point (SFPP) s The test was carried out by the procedure substantially as described in EP-A-0,403,097 and is a variation of the CFPP test.
iP~ax Appearance 'Temperature {t,~a4'f) This is a measure of the onset of crystallisation and hence the Cloud Point and was determined by Differ~ntia! scanning Caiorimetry (USC). Thus, a small sample {25 ~.I) of test fuel is cooled at 2°Clminute from a temperature at feast 30°C above the expected cloud point of the fuel. An exotherm is observed when t s crystallisation commences in the sample and the ir1lAT is measured by an extrapolation technique using a Mettler TA 200013 differential scanning calorimeter.
~ ESUt.'T~
~o The results are shown in the tables below.
'Table 1 Additt~e(s) CFPP ~F~P
~xar~lple (C~ncentrat~on en pprn) (C) C) 1 None -2 Not measured 2 X {4'15) -1 -3 3 1 (3) 0 2 4 2 {8) _1 2 1 (8); X (415) -12 -'9 I

6 2 (3); X (415) -'i 2 -12 iCEY: Fuel A was used in each of examples 1 to 6 Additive X was ~ mixture of Additives 4, 5, 6, 7 and 8 in the weight ratio of 1:3:2:3:2.

'WO ')3/I~t178 PCT/EP93/00~81 . . ; . , ;., -~ ,.. - 20 -.. tJ
Table 2 Example Fuel Additive ~elta ltVAT
(Concentration in ppm) (C) 7 ~ A None 0 8 A - 3 (300) 5.8 9 A 2 (300) 3.5 B None 0 11 B 3 (300) 1.8 12 B 2 (300) 1.5 KEY: Delta ~fllAT is the difference in 11~AT between the untreated and the 5 treated fuel and therefore measures Cloud laoint ~epression.
The results of Table 1 show the synergy of derrmlsifier additives (i.e. 1 and 2) with other additives in filterability tests, and tho:>e of Table 2 show the effectiveness of demulsifier additives (i.e. 2 anti 3) in producing aloud point o depression.
TabBe 3 Example Ad~ii~ive ~~PP
(~onceniratidn ira ppr~) ,t 0 6 9 o C

13 I~~ne FAIL (4~) 14 20 FAIL (-8) 10a ' 20 =10 18 100 200 20 ~~ ~

1'T 1~0 EAIL ~-8)' 1 s Examples 13 to 18 were carried ~ut i~ Fu~l C. The r~s~its show that aFPI~
pertorr~aroce wa,s ~nha:nc~d when the demu~sifi~r (Additive 9)-was used in corrabin~,tion ~rith one or bath of the cold flow additives Additives 10 end fi) as in Examples 15 and 16:

Claims (21)

CLAIMS:

1. An additive composition comprising:
(i) one or more non-metallic flow improving oil soluble addition products or condensates capable of improving, either jointly or singly, one or more cold flow properties of a crude oil or fuel oil; and (ii) a non-metaAic oil soluble demulsifier for crude oil- or fuel oil-water emulsions, said demulsifier having a hydrophobic part and a hydrophilic part and being selected from Groups I and II below where Group I is a condensate comprising, as the hydrophobic part, a part derived from a precursor having one or more groups capable of a condensation reaction to form oxyalkylated groups, bonded to one or more oxyalkylated groups comprising the hydrophilic part, and Group II
is a compound having a sulphonate or sulphonic acid group as the hydrophilic part, attached to the hydrophobic part; provided that the component (i) is not a combination of a substituted succinic acid derivative and an ethylene-vinyl acetate copolymer.

2. The composition of claim 1 in admixture with a major proportion of a crude oil or a fuel oil, the composition constituting a minor proportion.

3. The composition of claim 1 dispersed in a liquid medium compatible with a crude oil or a fuel oil to form a concentrate.

4. The composition of any one of claims 1 to 3 wherein the demulsifier is of Group 1 where the hydrophobic part is derived from a precursor having one or more hydroxy groups, one or more of which hydroxy groups having been condensed to form the oxyalkylated groups bonded thereto.

5. The composition of claim 4 wherein the precursor has the general formula:
where R represents an aliphatic hydrocarbyl group having from 3 to 24 carbon atoms, and n represents an integer from 4 to 20.

6. The composition of claim 4 wherein the precursor is a linear mono- or poly-hydroxy compound, one or more of the hydroxy groups of which have been condensed to form the oxyalkylated groups.

7. The composition of any one of claims 1 to 4 wherein the demulsifier is of Group 1 where the hydrophobic part is derived from a precursor having one or more primary, secondary or tertiary amino groups or quaternary ammonium groups, one or more of which groups having been condensed to form the oxyalkylated groups bonded thereto.

8. The composition of any one of claims 1 to 7 wherein the demulsifier is of Group 1 where the or each oxyalkylated group has up to 50 oxyalkyl units per group capable of a condensation reaction, each such oxyalkyl unit having from to 6 carbon atoms.

9. The composition of claim 2 or any one of claims 4 to 8 wherein the oil is a fuel oil and the demulsifier is present therein in a proportion by weight that is not greater than 50 ppm.

10. The composition of claim 2 or any one of claims 4 to 8 wherein the oil is a middle distillate fuel oil.

11. The composition of any one of claims 1 to 10 wherein the flow improving addition product or condensate is selected from one or more of:
(a) an ethylene-vinyl ester copolymer (b) a comb-like polymer (c) a polar nitrogen-containing compound or compounds comprising an amore salt or an amide or both formed by reacting at least one molar proportion of a hydrocarbyl substituted amine with a molar proportion of a hydrocarbyl acid having 1 to 4 carboxylic acid groups or its anhydride.

12. The use of an additive composition as defined in claim 1 for improving the cold flow properties of a crude oil or a fuel oil.

13. The use of claim 12 wherein the demulsifier is of Group 1 where the hydrophobic part is derived from a precursor having one or more hydroxy groups, one or more of which hydroxy groups having been condensed to form the oxyalkylated groups bonded thereto.

14. The use of claim 13 wherein the precursor has the general formula:
where R represents an aliphatic hydrocarbyl group having from 3 to 24 carbon atoms, and n represents an integer from 4 to 20.

15. The use of claim 13 wherein the precursor is a linear mono or poly-hydroxy compound, one or more of the hydroxy groups of which have been condensed to form the oxyalkylated groups.

16. The use of claim 12 or 13 wherein the demulsifier is of Group 1 where the hydrophabic part is derived from a precursor having ane or more primary, secondary or tertiary amino groups ar quaternary ammonium groups, one or more of which groups having been condensed to from the oxyalkylated groups bonded thereto.

17. The use of any one of claims 12 to 16 wherein the demulsifier is of Group where the or each oxyalkylated group has up to 50 oxyalkyl units per group capable of a condensation reaction, each such oxyalkyl unit having from 2 to ~6 carbon atoms.

18. The use of any one of claims 12 to 17 wherein the oil is a fuel oil and the demulsifier is present therein in a proportion by weight that is not greater than 50 ppm.

19. The use of any one of claims 12 to 18 wherein the oil is a middle distillate fuel oil.

20. The use of any one of claims 12 to 19 wherein the flow improving addition product or condensate is selected from one or more of:
(a) an ethylene-vinyl ester copolymer (b) a comb-like polymer (c) a polar nitrogen-containing compound or compounds comprising an amine salt or an amide or both formed by reacting at least one molar proportion of a hydrocarbyl substituted amine with a molar proportion of a hydrocarbyl acid having 1 to 4 carboxylic acid groups or its anhydride.

21. The use of any one of claims 12 to 20 wherein the demulsifier has a Relative Solubility Number of from 4 to 25.