CA2068173A1 - Identification of liquid hydrocarbons using chemical markers - Google Patents

Abstract

The present invention relates to a composition, a method for preparing a composition, and a method for analyzing the composition where the composition includes a liquid hydrocarbon and one or more marker compounds of formula (I) where Y is selected from X-R2 or NR3R4, and where X is an oxygen atom or a sulfur atom, R2 is an organic radical having from about 1 to about 30 carbon atoms, R3 and R4 are the same or different organic radical having from about 1 to about 30 carbon atoms The markers can be present in the amounts from about 05 parts per million to about 50 parts per million, preferably from about 05 to about 25 parts per million and preferably from about 1 to about 10 parts per million and is usable to identify not only the source and identity of the particular hydrocarbon liquid, but also to allow expedient tracing of the hydrocarbon back to its source and analysis of the particular type of additives that may be present and to what extent they are present in the hydrocarbon. J:\\NALD\\020\\PA\\01.str

Description

2 ~ 7 ~

FIELD OF THE INVENTION

This invQntion relates to the use of specific chemical compounds a~ chemical markers to be added to liquid hydrocarbons in low concentrations in order to uniquely mark the liquid hydrocarbon so that it can be quickly identi~ied with respect to its source and integrity The chemical mar~ers can also be premixed with any p-r~ormance enhancement pac~age to further allow identification of th~ typ- and amount of the package present in the hydrocarbon liquid 8ACXGROU~D OF T~E I~VENTION

Numerous techniques have been used for marking liquid hydrocarbons for the purpose of identifying its source and integrity ~hes~ methods typically involve the incorporation o~
small amount~ o~ chemical additives or markers to the liquid Sub~qu-nt det-ction o~ th- mark-rs can be achi~ved by a number of ~tandard analytical techniqu-s such a~ colorimetry, IR, W or W-Vis spectroscopy, mass spectrometry, neutron activation or atomic adsorption spectroscopy Radioactive tracers or markers have also been used including the addition o~ tritium, iodine-131, or sulfur-35, in order to trac~ fuels in pipQlines and in oil storage facilities There are various circum~tances when it would be advantageous to determin- tho pr-~-nc- and concentration o~ a substance which had pr-viow ly be-n add-d to a hydrocarbon liquid The presence and conc-ntration o~ p-r~ormanc--enhancing additives in a hydrocarbon might b- in~-rred by m-a~uring th~ concentration o~ a specif1c sub~tanc- that wa~ co-injected into the hydrocarbon along with the primary additiv- Al~o, i~ a hydrocarbon liquid were accidentally discharged into the ~nvironment, th- sourc- o~ th- hydrocarbon might be dstermin~d by identifying a ~peci~ic uni~ue substance t~at had previou~ly b-en added to th~ hydrocarbon Similarly, the uniquely 2~81~^~

marked hydrocarbon could be monitored throughout its distribution network to verify its identity and aid in quality assurance programs that seek to prevent contamination with other hydrocarbon liquids.
For example, motor oil consists of a major amount of paraffinic hydrocarbon and a minor amount of a mixture of performance-enhancing additives. However, once mixed, it is difficult to determine the concentration of the additive package in the oil. If a known amount o~ an easily detectable substance were included in the additive packaq-, the concentration of the package in the oil could be inferred by determining the quantity of marker substance in the ~inished motor oil. This would simplify quality control measurements and allows identification of the oil once in service.
Thi~ can also be applied to additives that are blended into ga~oline, diesel fuels and other hydrocarbons.
In another example, environmental damage occurs when crude oil washe~ up on shore as a result o~ accidental or intentional discharge~ ~rom tank~r vessels. If all tanker ve~sels were required to in~ect small amounts o~ a marker substance into the hydrocarbon when on-loading their cargo, the source and responsibility of all spills could be determined and appropriate action taken.
Environmental damage and poisoning o~ ground water can result from the leakage of gasoline or fuel oils ~rom storage tanks. To determine the extent and location o~ such leakage, it would be desirable i~ the ~oil, ~luid or ground water adjacent to the storage ve~Qel could be coll-cted and then analyzed to d~termine if the tluid was escaping ~rom the vessel. Such lQaks commonly occur in tank ~arm~, ~ervic- tation underground tanks, pipelines and the like.
In U.S. Patent No. 4,141,692, Keller described the use of chlorinated hydrocarbon marking agents in liquid hydrocarbon environments. The marking agents were rQstricted to chlorinated hydrocarbons having at least 3 chlorine atom~, at least two carbon atoms and a Cl/C atom ratio of at least 1 to 3. The components were detectable using a electron capture detector after gas chromatoqraphic separation. Although the compounds were described ; 3 20~8~ 7~

as relatively non-toxic, the use of chlorinated hydrocarbons as markers has certain disadvantages. The most obvious disadvantage is that chlorinated markers used in liquid hydrocarbon fuels can produce potentially toxic oxidative break down products when the fuel is burned. The break down products also will generally add to increased amounts of chlorinated hydrocarbon emissions into the atmosphere, a potential risk to the ozone layer.
In U.S. Patent No. 4,209,302, Orelup described the use of 1-(4-morpholino)-3-~ or ~-naphthylamino) propanes in the concentration rangQ from 0.5 to 12 part per million (ppm) as potential marking agents for gasoline. These markers did not impart a color to the gasoline, but required "wet chemical" extraction followed by subsequent treatment with diazotized 2-chloro-4-nitroaniline to yield a pink solution which could be measured colorimetrically. The major di~advantage of this technique is the necessity for performing a preliminary chemical extraction prior to iden~ification and quantitation which can lead to increased errors in measurement.

SUMMARY OF THE INVENTION
This invention relates to a liquid composition containing a liquid hydrocarbon and one or more marker compounds or agents of formula (I) below:
' where Y is selected from X-R2 or NR3R~, and where X is an oxygen atom or a sulfur atom, ~2 is an organic radical having from about 1 ' ~

.

2 ~

to about 30 carbon atoms, R3 and R4 are the same or different organic radical having from about l to about 30 carbon atoms The pr-5~nt invention also relates to a method for preparing and a method for analyzing the composition with respect to the marker compound(s) identity and quantity Optionally, the liquid hydrocarbon can contain a performance enhancing package and the marker(s) can bQ added to the package prior to introducing the packag- into the hydrocarbon liquid Th- marker is added in sufficient quantities to ensure that identification and quantitation of the marker can be achieved Typically, the marker is added in a range from about 0 5 to about 50 parts p-r million (ppm) based on the weight of liquid hydrocarbon to be marked The addition of the chemical marker(s) allows the source and integrity of a hydrocarbon liquid to be determined as well as indirectly the type and/or amount of any performance enhancement - material or package added to a particular liquid h~,irocarbon to be determined Thus, an appropriately marked hydrocarbon liquid can be analyz-d to guard against mixing it with diff-r-nt typ-s of liquids Th- hydrocarbon liquid can include, but is not limit-d to, gasoline, lubricatin~ oils, crude oil, and the like The markers can also be used to identify the source of a liquid hydrocarbon which has been previously marked by a marking agent of the present invention The sourco identification can b- used to as~ess responsibility and potential liability for environmental damages Analysis of the marked liquid can also b- used to d-termine the typ- and nature of any liquid hydrocarbon 1-aks or ~pills ~SCRIPTION OF THE PREFERRED EM30DIMENT
The composition of the presQnt invention comprises a liquid ; hydrocarbon and one or more marker compound or ag-nt, said marker being pre~ent in su~icient quantity to facilitate subsequent analytical identification and quantitation and typically ranging from about 0 5 ppm to about 50 ppm based on the weight of the liquid 20~817~

hydrocarbon Preferably, the markers of the present invention are present in amount from about O S ppm to about 25 ppm and more particularlY, from about 1 ppm to about 10 ppm However, lesser and greater amount can be used The limitation on the low end regarding quantity is determined by the sensitivity of the analytical detectors The higher amount is controlled by convenience The markors are required to be soluble in the li~uid hydrocarbon at the particular level5 cho~en in order that accurate measurements can be mado The method o~ preparing a composition of the present invention compris-s the stops o~ adding one or more markers to a liquid hydrocarbon under mixing condition suf~icient to facilitate admixing o~ th- mixture into said liquid, said marker being present in su~ricient guantity to facilitate subsequent analytical identi~ication and quantitation typically ranging from about 0 5 ppm to about 50 ppm based on th- weight of tho liguid hydrocarbon to be marked Pr-~erably, the mark-rs o~ the present invention are pr-sont in amount ~rom about 0 5 ppm to about 25 ppm and more particularly, ~rom about 1 ppm to about 10 ppm The hydrocarbon liquid c~n optionally contain a per~ormance enhancing package and the markors can be added to the package prior to adding the packa~e to the liquid The method ~or analyzing the liquid composition o~ the present invention comprise~ the ~t~ps o~ analyzing a sample o~ said liquid compo~ition by an analytical m~thod, said liquid composition comprising a liguid hydrocarbon and one or more markers in su~ici-nt quantity to ~acilitate subsequent analytical id-ntification and guantitation and said analytical method being su~icl-nt to d-t-rmin- th- id-ntity and concentration of the mark-r(~) contain-d in th- liguid composition The marker~ can be pr-sont in the rang- ~rom about 0 5 ppm to about 50 ppm ba~ed on the weight o~ the liguid hydrocar~on to be marked Pr-~erably, the markers o~ the presont invention are present in amount from about 0 5 ppm to about 25 ppm and more particularly, ~rom about 1 ppm to about 10 ppm The hydrocarbon liquid can optionally contain a , . . . .

2~

performanCe enhancing package and the markers can be added to the package prior to adding the package to the liquid The analytical methods useful in the present invention include, but is not limited to, gas chromatographic separation followed by component detection using a detector such as an electron capture detector, a mas~ spectrometer, a flame photometric detector, ~lectrolytic conductivity detector, microcoulometer, chemilumin~scence detector, a nitrogen phosphorous detector, a photoionization dQtector~ infra-red spectrometer, ultra violet sp-ctrom~tQr, fluorescence detector, microwave inductive plasma d-t-ctor, gas density balance detector, ultrasonic detector or other ~imilar d-tectors, high performance liquid chromatographic s-paration followed by component detection using one of the above llst~d d~tectors, or other analytical methods capable of identifying and quantifying th- markers Gas chromatography followed by componsnt det~ction u~ing an electron capture detector is preferred Th~ mark~rs aro compounds of formula (I) ~D2 L
, ~
~o~

whor- Y i~ ct-d ~rom X-Rl or NR2R3, and where X is an oxygen atom or a ~ul~ur atom, R1 is an organic radical having from about 1 to about 30 carbon atoms, R2 and R3 are the same or different organic radlcal having from about 1 to about 30 carbon atoms The term organic radical used to describ~ Rl-3 includes substituents selected from the illu~trativs and reprQsQntative group consisting of a hydrogen atom, a linear or branched al~yl having from about 1 to about 30 carbon atoms, an aryl group having from about 6 to about 2 ~ 7 3 30 atoms, a cycloaliphatic group having from about 3 to about 30 carbon atom~, a heterocyclic group, a substituted alkyl group, a substituted aryl group, a diol, a polyol, an alkylated or acylated glycol, an alkylated or acylated polyglycol, and alkylated or acylated ethylene polyamine Preferably, Rl is selected from the illustrative and representative group consisting of a linear or branched alkyl group having from about 1 to about 30 carbon atoms, an alkylated glycol and an alkylated polyglycol The liquid hydrocarbon can be selected from the illustrative and repr-sentativ- group consisting of crudQ oil, residual oil, lubricating oil, hydraulic and circulating oils, heating oil, diesel ~uel and mid-distillates, jet ~uel, aviation fuel, gasoline, gasohol or alcohol oxygenated gasoline components such as MTBE, fuels, polymer lattice~ and solutions, and bulk liquid polymers and mixtures thereof and similar hydrocarbon liquids or liquid mixtures The per~ormance enhancing package can comprise mixtures of components s-lect-d from the illustrative and representative groups consisting of detergents, dispersants, corrosion inhibitors, anti-oxidants and stabilizers, wax crystal modifi-rs, EP and anti-wear agents, emulsion breakers and dehazers and octane enhances Each marker represonted by formula (I) can be used indep-nd~ntly or in combination to mark a particular liquid hydrocarbon Thus, th- m-thyl and ethyl derivatives could be added togother or used indep-nd-ntly a~ a marking agent, along with any o~
the other higher alkyl analogs Alternately, a set of n markers of formula (I) can bs us-d to e~tablish a tagging cod~ by adding to ach dist~nct hydrocarbon liquid in a given sequence o~ quantities o~ ach of th- n markers Thus, using 3 distinct markers of formula (I), A, B, and C, and 2 distinct quantitative values of the markers suc~ as l and 2, on- could uniquely tag 8 liquid hydrocarbons as shown b-low 1 ~lA,lB,lC); 2 (lA,lB,2C); 3 (lA,2B,lC); 4 (2A,lB,lC);
(lA,2B,2C); 6 (2A,lB,2C); 7 (2A,2B,lC); and a. (2A,2~,2C) It can readily be seen that this coding process obeys the 5 formula of Mn coding sequences where M are the allowed quantities 2~ 3 such as lOppm, 20ppm, 30ppm, etc and n is the number of markers The numeric value of n which corresponds to the number of markers used in a give sequence can range from about 2 to about 20 markers or more The number of allowable marker quantities or levels, M, S used in a given sequence can range from about 2 to about lo different quantities or more The exact number of markers, n, and th- nu~b-r of 1QVe1SI M, used in a given sequence will be dictated by conv-nience and simplicity The quantitative values can be separatod by an increment of from about 1 to about 20 ppm and preferably from about 5 to about 10 ppm again with necessity and convenience dictating the exact increment Although the general formula for enumerating the coding sequences is Mn, when one of the allowed quantitative levels is zero, or the absence of a marker, then the number of usable sequences is reduced by one which would corre~pond to a sequence where no markers are added Compound~ of Formula (I) can typically be prepared by the reaction of 3,5-dinitro benzoic acid or its reactive analogs, including the acid chloride, bromide or the anhydride, with either an alcohol, a thiol or an amine Thus, when Y i9 equal to X-R1 the compound of Formula (I) can be prepared by reacting 3,5-dinitro benzoic acid or a reactive analog with an alcohol or thiol where Rl is selected from the illu~trative and repre~-ntative group consisting of a hydrogen atom, a lin-ar or branched alkyl having from about 1 to about 30 carbon atom~, an aryl group having from about 6 to about 30 atoms, a cycloaliphatlc group having from about 3 to about 30 carbon atoms, a h-t-rocyclic group, a sub~tituted alkyl group, a substituted aryl group, a diol, a polyol, an alkylated or acylated glycol, an alkylat-d or acylated polyglycol, and alkylated or acylated ethylene polyamine Pre~-rably, R1 is selected from the illustrative and representative g~oup consisting of a linear or branched alkyl group having from about 1 to about 30 carbon atoms, an alkylated glycol and an alkylated polyglycol ~8~ 7 ~

The alcohols useful in the preparation of markers of formula (I) includ~, but are not limited to, methanol, 2-methoxyethanol, 2-- ( 2-methoXyethoxy) ethanol, ethanol, 2-ethoxyethanol, 2 - ( 2 -ethoxyethOXy) ethanol, propanol, 2-propoxyethanol, 2- ( 2-propoxyethoxy) ethanol, 2-propanol, 2-methy1-l-propanol, 2-methy1-2-propanol, butanol, 2-butoxyethanol, 2-(2-butoxyethoxy)ethanol, 2-butanol, 2-methyl-1-butanol, 3-methyl-1-butanol~ 2-ethyl-1-butanol, n-pentanol, 2-pentanol, 2-pentoxyethanol, 2- ( 2-pentoxy-thoxy) ethanol, 2-methyl-1-pentanol, 4-methyl-2-pentanol, 2, 4-dimethyl-3-pentanol, 3-methyl-~-pentanol, hexanol, 2-hsxoxyethanol, 2- (2-hexoxyethoxy) ethanol, 2-hexanol, 3-hexanol, 2-ethyl-l-hexanol, 3,5,5-trimethyl-1-hexanol, heptanol, 2-heptanol, 3-heptanol, 2, 6-dimethyl-4-heptanol, octanol, 2-octanol, 3-octanol,

3, ~-dimethyl-l-octanol, nonanol, and d~canol The analogous thio1 roag-nt~ can b~ u~d to pr~paro sulfur analog~ of the benzoate comE~ound~ derived ~rom th- above listed alcohols Wh-n Y i~ equal to NR2R3 th- compound can b- prepared by reacting 3, S-dinitro b-nzoic acid or a reactiv- analog with an appropriate amin~ where R2 and R3 are the same or di~erent and are s-lect~d ~rom the illustrative and representative group consisting o~ a hydrog-n atom, a lin-ar or branched alkyl having from about 1 to about 30 carbon atoms, an aryl group having from about 6 to about 30 atoms, a cycloaliphatic group having from about 3 to about 30 carbon atom~, a h-terocyclic group, a substituted alkyl group, a sub~titut-d aryl qroup, a diol, a polyol, an alkylated or acylated glycol, an alkylated or acylat-d polyglycol, and alkylated or acylat-d ethyl-n- polyamin- Pr-ferably, R2 and R3 are selected from th- illu~tratlv- and representative group consisting of a 1 inear or branched alkyl group having ~rom about 1 to about 3 o carbon atom~, an alkylated glycol and an alkylated polyglycol The amin-~ u~e~ul in the preparation o~ marker~ o~ ~ormula (I) include, but are not limited to, linear primary amines such as methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, nonylamine, decyl amine, 3S branched primary analogs, dialkylamin~ such as dimethylamine, 20~1 73 diisopropylamine, dipropylamine, dibutylamine, di-sec-butylamine~
dip-ntylamin-, dihexylamine, di-(2-ethylhexyl)amine and dioctylamin-, and mixed dialkyl amine~ such as methylethylamine, methylbutylamine~ ethylhexylamine and the like As mentioned previously, the preferred analytical detection method is gas chromatography (GC) using an electron capture detector ~ECD) to d-termin- the concentration and identity of the specific ~arker(~) in the liquid composition The ECD detects a chemical compound by the compounds ability to capture electrons present in th- d-t-ctor a~ th- compound passes out o~ a GC separation column and into and through th- ECD
Ga~ chromatography separates chemicals accordinq to their int-raction with a given GC column stationary phase at a given constant t-mperature or according to a given temperature program A temperature program is a computer controlled sequence of t-mporatur- incr-a~-~ or decreases utilized to enhance chromatographic s-paration and the short analysi~ time Each ch-mical compound interacts difterently with a giv~n stationary pha~e under given temp-ratur- condition which caus-~ ach particular compound to hav- a unique retention t~me, the di~erenc- between the tim- the compo~ition is introduced onto the column and the time a giv-n compon-nt Qxits from th- column and is detected by a detector The r-tention tim-, onc- d-t-rmined, can b- used to identify the marker whil- th- p-ak area can be used to d-t-rmine the conc-ntration ot th- mark-r The identity o~ th- particular markers ean th-n b- w -d to id-ntify the sourc- ot th- particular hydrocarbon, as w-ll a~ id-nti~ying the nature o~ th- hydrocarbon liguid Thus, it th- hydrocarbon liquid contains a performance enhanc-m-nt mat-rial or packag- to which a marker has been added, th-n th- conc~ntration ot th- package as well as th- nature o~ the particular packag- and liquid can be determined by the GC ~ethod of analy~is .
Th- stationAry phases usetul to separat- and identify the markers ot the pr-s~nt invention are silicones selected from the illustr~tive and representative group consisting of 2 ~ 7 ~

dialkylpolYsilOxanes, alkylarylpolysiloxanes, substituted alkylarylpOlYsiloxanes~ copolymers thereof and mixtures thereof and carbowaXe9, where the alkyls have from about 1 to about 10 carbon atoms, the aryls have from about 6 to about 14 carbon atoms, and the substituted alkyls are cyanoalkyls, dialkylaminoalkyls, alkoxyalkyls, and haloalkyls and where copolymers means any polymer comprising two or more of the above listed homopolysiloxanes unlts Pr~ferably, th~ materials are selected from the group consisting of dimsthylpolysiloxane, phenylmethyl polysiloxane and cyanopropylphenyl-methyl polysiloxane The GC columns can be packed or unpacked both of which are standardly known in the art The column can be coated or packed with the stationary phase as is standardly known in the art For a qeneral di~cussion of GC separation and analysis, see l~Modern Practic- of Gas Chromatography", edited by Robert L Grob, published by John Wiley and Sons The lectron capture detector is described in many publications such a~ the tsxtbook entitled, "Modern Practice of Gas Chromatography", edited by Robert L Grob, published by John Wiley and Sons (see particularly pages 255-267) Since electron capture detection is a well-known technique, it i9 not described here in any greatsr detail - The preferrad GC process of the present invention comprises the steps of 1) injecting a liquid compo~ition comprising â liquid hydrocarbon and one or mor- markers onto a first end of a first GC
column through an in~-ctor port equipped with a carrier gas supply which 9uppli-- a carri-r ga~;
2) ~-parating said markers from a major portion of said liquid into on- or mor- discrete peaks on said first column;
3) opening a valv- conn-cted to a s-cond end of ~aid ~irst column for one or mor- time windows;

4) collecting each of said marker- corre~ponding to each of said window~ into a cold trap comprising a fir~t end of a second GC
cooled by a coolant;

2~17^3

5) removing said coolant from said cold trap;

6) further separating said makers on said second column; and det~cting each of said makers with an electron capture detector equipped with a make up gas, S said first column containing a first column stationary phase and being of a first length suf~icient to affect an initial or partial separation o~ ths marker from said major portion of said l~quid, said windows corresponding to one or more retention times of sa~d markQrs and being o~ sufficient duration to allow all or nearly all, but prQferably all, of each marker to pass therethrough, and said second column containing a second column stationary phase being the same or di~er-nt from said first stationary phase and being of a second length ~ufficient to separate each o~ said markers from any other compon-nt~ in said liquid The valve opening is typically controlled by a computer system wh-r- th- operator would input into the computer the retQntion times corre~ponding to each marker and the duration o~ the window during which tim~ the valve will b- in an open condition At all other times, the valv- will remain in a closed condition and the non-marker components of the liquid will either simply exit the first column or b- introduced into an optional second detector usually a ~lame ionization d-t-ctor Th- duration o~ the window is set so that th- valve opens su~iciently be~ore the marker peak arrives at the valve and r-main~ op-n su~iciently arter the mark-r peak to in-ur- that all or n-arly all, but pre~erably all, o~ the marker peak i- d-posit-d into th- cold trap Th- ma~or portion o~ th- liquid composition is comprised of , non-polar hydrocarbons, but the composition can al~o contain minor i polar or oth-r components It ~hould be r-cognized that the minor polar compon-nt o~ th- liquid could possibly be contained within any one o~ said windows This po~ ibility is one o~ the reasons for employing a doubl- column GC method The second column insures complete separation o~ said markers ~rom any other components in said liquid Th- second column al~o insures sup-rior id~nti~ication and quantitation o~ said markers 2~ 7~

The term peak as used in the present invention is meant to refer to th- band or front of molecules moving through the columns that are composed primarily of the marker molecules The coolants useful in the present invention can be selected from the illustrative and representative group consisting of carbon dioxide, nitrogen, a freon, an alcohol, a glycol or any other similar cooling gas or liquid Th- column stationary phases are as previously described, pr-fer-ntially th- stationary phases are different; one phase being ot a di~erent polarity than the other phase Thus, the first stationary phase could be an arylalkyl polysiloxane while the second stationary phass could be a dialkyl polysiloxane or vis-a-versa The polarity of different typically used silicones is generally ~nown in the art The stationary phase can either be packed into the column absorb-d on an inert carrier or preferably coated on the colu~n~ to a thickn-ss from about 0 1 to 1 5 micron~
Th- column~ pr-~-rred for this invention ar- columns having a diam-ter from about 0 1 to 0 7 millimeters, pr-ferably from about 0 18 to O S3 millimeters with 0 25 to 0 53 millimeters being particularly preferred The columns are known as capillary columns in th- art The l-ngth of the first column is preferably shorter than th- l-ngth of the second column and being from about 5 to about 60 meter~ with from about 10 to 20 meters being preferred and fro~
about 12 to about 18 mat-rs being particularly pr-~erred The length of th- s-cond column i~ from about 10 to about 60 meters with 20 to 40 m-t-r~ b-ing pr-f-rr-d and from about 25 to about 35 meters b-lng particularly pr-r-rr-d Th- in~-ctor port is maintained at a temperature su~icient to in~ur- that all th- components are vaporized before entering the fir~t colu~n, typically from about 250C to about 300C The method can ith-r b- carri-d out in an isothermal condition, a constant temperaturQ condition where thQ i~othermal temperature can generally be from about 175C to about 275C The method can also be per~ormed using temperature programming Temperature programming allow~ the temperature of the method to be either increased or 2 ~ 7 ~

decreased at a given rate measured in C/minute The exact temperature program used is highly subjective and any appropriate temperature prosramming sequence generally used in the art can ~e applied to the present method Preferably, the method is performed using temperature programming The carrier gas is an inert gas used in GC to establish a so called mobil phase while the silicone stationary phase establishes thQ 90 called stationary phase, both of which are well known in the art and are responsible for accomplishing separation because different molecules spend different amount of time in each phase pre~erred carrier gas is h~lium and the preferred make up gas is nitrogen ~ he makeup gas used by the electron capture detector is nitrogen or a mixture of argon/methane i~ the carrier gas is helium, nitrogen if the carrier gas is nitrogen, and nitrogen or a mixture of argon/methane i~ the carrier gas is hydrogen In order to be a useful marker for the present invention, the compound must be chlorine free and contain groups which have high electron a~finities illustrated by nitro and nitrate compounds, carbonyls, nitriles and organo-metallic compounds, compounds containing conjugated double bonds, certain aldehydes and ketonic groupings having a conjugatod system A list of typical electrophoric compounds that would be illustrative of groupings and compounds capable o~ ctron capture detection is givsn in "Modern Practic- o~ Ga~ Chromatography" on pag- 266 The di~clo~ure of which her-in is incorporat-d by r~ference ThQ dosag- of th- marker compounds containing the electrophoric groupings i~ within the range of 0 5-50 parts per million (ppm), with a typical dosag- being 1-10 ppm ~n most ca~e~ when the treated liquid hydrocarbons or the fuel into which the additive pac~age has been placed are tested, it is possiblQ to detect the presence of the mar~er compound at a dosage as low as O S ppm In certain instances even lower dosages can be detected 2~8~ 73 The present invention can be further understood and additional aspects can be discerned from the following illustrative and representative examples.

PREPARATIo~ OF MARXERS OF FORMULA (I

This example illustrated the general preparation of 3,5-dinitrobenzoate~ and thio benzoates by esterification of 3,5-dinitrob-nzoic acid with a ~uitable alcohol or thiol This particular examplQ depicts the preparation of 2-ethylhexyl-3,5-dinitrobenzoat-To a 250 Ml 4-necked glass reaction flask with a stirri~q paddl-, thermometer, dean stark trap with condenser and a gas inlet adaptor wa~ added approximately 106 1 grams (0 5 moles) of 3,5-dinitrobenzoic acid, 7$ 6 grams of 2-ethylhexanol (0 55 moles) and 0 1 gram~ of methane sulfonic acid The mixture wa~ heated to 140C
and ~ochanically ~tirred After one hour, vacuum was ~lowly applied to th- v-ss-1 until a mild reflux was obtained The reflux was continu-d for two hour~ at 140C and water was collected in the dean stark trap until the acid value of the pot material was below 8 milligrams potas~ium hydroxide (KOH) per gram of material (95%
esterification) The ve~sel was cooled below 100C and then 50 Ml of 1 0 M aqueou~ pota~ium carbonate was added After thorough mixing, th- ba~e wa~h was discarded After a subsequent water wash, the ve~8-l wa~ r-h-ated to 140C and vacuum wa~ applied to remove any r--idual wat-r and alcohol Thi~ xampl- illu~trated the preparation of n-decyl-3,;-dinitrob~nzoat-~ according to tho procedure described in Example 1 except 10 60 grams (0 05 mole~) of 3,5-dinitrobenzoic acid and 8 ~2 grams (0 055 moleq) of decyl alcohol were used E~e~,~

20~ 73 Thi~ example illustrated the preparation of the 2-t2-hexoxy-thOXy)Qthyl-3~s-dinitrobenzoate according to the procedure describsd in Exampl~ l except 10 60 grams (o OS moles) of 3, 5-dinitrob-nZOiC acid and 9 6 grams (0 05S moles) of 2-(2-hexoxyethoxy)ethanol were used This reaction can also be performedby using a heterogeneou~ acidic catalyst instead of methyl sulfonic acid such as Amberlyst 15 ~MP~E 4 Thi~ xampl- illustrated the preparation of the 2-hexoxyethyl-3,5-dinitrob-nzoat- according to th- procedure described in Example 1 except 42 42 gram~ (0 2 molos) of 3,5-dinitrob-nzoic acid, 30 71 grama (0 21 mole~) o~ 2-hexoxyethanol, 5 grams of Amberlyst 15 and 2S Ml o~ toluene were u~ed Thi~ xample illustrat~d the preparation of 2-(2-ethoxyethoxy) ethyl-3,S-dlnitrobenzoate~ according to the procedurc de~cribed in Exampl- 1 xc-pt 42 42 gram (0 2 mole~) or 3,S-dinitrobenzoic acid, 2028 28 gram- (0 21 mole~) of 2-(2-ethoxy-thoxy)-thanol, 5 grams of Filtol 13 LM (a~ catalyst) and 25 Ml o~ toluene were used This example illu~trat-d the preparation o~ l-methyl-2-25propoxyethyl-3,5-dinitrob nzoat-~ according to the procedure d--cr~b-d in Exampl- 1 xc-pt 42 42 gram~ (0 2 mol-~) o~ 3,5-dinitrob-nzo~c acld, 24 81 gramn (0 21 mol-s) o~ propyl propasol, 3 3 gram- o~ Amb-rly-t 15 (aa cataly~t) and 25 Ml o~ tolu-ne were u--d ~æz.~z Thi~ example illustrat-d the preparation o~ 2-~2-propoxyethoxy) ethyl- 3,5-dinitrobenzoates according to the procedure described in Exampl- 1 except 42 42 gram~ (0 2 moles) o~ 3,5-dinitrobenzoic acid, 2~gl 7.~

27 8 grams (0 21 moles) of 2-(2-propoxyethoxy)ethanol~ 5 grams of Amberlyst 15 (a~ catalyst) and 25 Ml of toluene were used This example illustrated the preparation of the 2-propoxyethyl-3,5-dinitrobenzoate according to the procedure described in Example 1 exc~pt 42 42 grams (0 2 moles) o~ 3,5-dinitrobenzoic acid, 18 5 grams (0 21 mole~) o~ 2-propoxyethanol, 5 grams of Amberlyst 15 (instead of methan- sulfonic acid) and 25 mL of toluene were used Although example 1-8 ar- specific in examples of the preparation of markers of formula (I) using the general procedure of Example 1, it should be appreciated that this same technique can be applied with equal ease to any other alcohol or analogous thiol and listed and generally enumerated in the specification This xample illustrated the general preparation of 3,5-dinitrobenzoates and thio benzoates by esterification of the acid chlorido of 3,5-dinitrobenzoic acid (DNBC) with a suitable alcohol or thiol This particular example depicts the preparation o~ the 2-butoxyethyl ester of 3,5-dinitrobenzoic acid To a glas~ reaction flask was added 115 3 grams (0 5 moles) of 3,5-dinitrobenzoyl chloride Then 65 grams (0 55 moles) of 2-butoxyethanol wa~ add-d all at once and a slow nitrog-n purge through th- ve~sel and into a wat-r trap was begun The mixture was stirr-d wlthout h-atlng ~or thirty minutes then warmed to 800C for thirty minut-s Th-n tho product was washed twice with 50 Ml of 1 0 M aqueou- potas~ium carbonat- and once with water The vessel was then h-at-d to 140 C and vacuum was applied to remov- residual water and alcohol 2 ~ 7 ~

This example illustrated the preparation of the ethyl-3,5-dinitrobenzoates according to Example 9 except that 23.06 grams (0.
moles) of DNBC and 50 mL of ethanol were used.

S ~AMPLE 11 This example illustrated the preparation of the pentyl-3,5-dinitrobenzoates according to Example 9 except that 23.06 grams (0.1 moles) of DNBC and 9.25 grams (1.2 equivalence) of pentanol were used .

E,~EL~
Th$s example illustrated the preparation of the hexyl-3,5-dinitrobenzoates according to Example 9 except that 23.06 grams (0.1 moles) of DNBC and 10.73 grams (1.2 equivalence) of hexanol were u~-d.

Thio example illustrated the preparation of the octyl-3,5-dinitrobenzoates according to Example 9 except that 23.06 grams (0.1 moles) of DNBC and 13.76 grams (1.2 equivalence) of octanol were us-d.

This example illustrated the preparation of the decyl-3,~-dinitrobenzoates according to Example 9 except that 23.06 grams (0.1 moles) of DNBC and 16.62 grams (1.2 equivalence) of decanol were used .

~.~
Thi~ exampl< illustrated the preparation of the 2-(2-butoxy~thoxy) ethyl- 3,5-dinitrobenzoates according to Example 9 except that 23.06 grams (0.1 moles) of DNBC and 17.33 grams (1.2 equivalence) o~ 2-(2-butoxyethoxy)ethanol were u~ed.

2Q~ 73 This example illustrated the pr~paration of the 2-(2-methoxyethOXY) ethyl- 3,5-dinitrObenZOateS according to Example 9 except that 23 06 grams (0 1 moles) of DN8C and 12 62 grams (1 2 equivalenCe) of 2-(2-methoxyetboxy)ethanol were used ,. S

This exampl- illustrated th- preparation o~ the 2-methoxyethyl-3,5-dinitrobenzoat-s according to Exampl- 9 xc-pt that 23 06 grams (0 1 mol--) of DNBC and 8 00 grams (1 2 quivalence) of 2-~hoxy-thanol w-re us-d ';

Thi~ example illustrated the preparation o~ the 2-methyl-1-p-ntyl-3,5-dinitrobenzeate~ according to Example 9 except that 15 00 lS gram~ (0 06S mole~) of DN~C and 8 00 gram~ (1 2 equivalence) of 2-m-thyl-1-p-ntanol w~r~ used ' Thi~ ~xampl- illu~trat-d th~ pr~paration o~ the 4-methyl-2-p-ntyl-3,5-dinitrob-nzoat-- according to Example 9 except that lS 00 grams (0 06S moles) of DNBC and 8 00 gram~ (1 2 equivalence) of 4-- methyl-2-pentanol were used :, ~.~
Thi~ xampl- illu~tratad the preparation o~ th- 2,4-dim-thyl-3-p-ntyl-3,S-dinitrob nzoat-- according to Exa~pl- 9 xcept that 15 00 gra~- (0 06S mol-a) o~ D~BC and 9 07 grams (1 2 equival-nce) o~ 2,4-dl~-thyl-3-p-ntanol w r- u~-d 82~oeL~_ZL
Thi~ xa~pl- illu~trat-d the pr-paration of the l-h-ptyl-3,5-dinitrob-nzoat-s according to Example 9 exc~pt that 15 00 grams (0 065 mol--) of DNBC and 9 07 gra~s (1 2 equival-nc-) o~ l-heptanol w~re us-d ,:, .

`'~ ' .

2~3~7~

This example illustrated the preparation of the 2-octyl-3,s-dinitrobenzoates according to Example 9 except that lS.Oo grams (0.065 moles) of DNBC and 10.17 grams (1.2 equivalence) of 2-octanol S were used.

This example illustrated the preparation of the 3,5,5-trimethyl-l-h-xyl 3,5-dinitrobenzoates according to Example 9 except that 15.00 grams (0.065 moles) of DNBC and 11.25 grams (1.2 equivalence) o~ 3,5,5-trimethyl-l-hexanol were used.

,EXAMPLE 24 This example illustrated the preparation of the 3,7-dimethyl-1-octyl-3,5-dinitrobenzoates according to Example 9 except that 15.00 gram~ (0.065 moles) o~ DNBC and 12.35 grams (1.2 equivalence) of 3,7-dimethyl-1-octanol were used.

This example illu~trated the preparation of the 2-methyl-1-butyl-3,5-dinitrobenzoate according to Example 9 except 2-methyl-1-butanol was used in place o~ 2-butoxyethyanol.
..

This example illustrated the preparation or the 3-methyl-1-butyl-3,5-dinitrob-nzoat- according to Example 9 except 3-methyl-l-butanol wa~ u--d in place o~ 2-butoxyethyanol.

~X~PLE 27 This example illu~trated the preparation of the methyl-3,5-dinitrobenzoat- accordin~ to Example 9 except methanol was used in place o~ 2-butoxyethyanol.

2 ~ 7 ~

This example illustrated the preparation of the 2-ethyl-1-butyl-3~5-dinitrobenzoate according to Example 9 except 2-ethyl-1-butanol was used in place of 2-butoxyethyanol Although example 9-28 are specific examples of the preparation of markers of formula (I) using the general procedure of Example 9, it should b~ appr-ciated that this same technique can be applied with ~qual oa~ to any oth-r alcohol or analogous thiol and listed and gen-rally enumerated in th~ ~pecification This example illustrated the general preparation of 3,s-dinitrobenzamides by amidization of the acid chloride of 3,s-dinitrobenzoic acid (DNBC) with a suitable amine This particular lS example depicts thQ preparation of N,N-dibutyl-3,5-dinitrobenzamide To a glass reaction flask wa~ added 46 1 g (0 ~ moles) of 3,5-dinitrob-nzoyl chlorid- and 120 grams o~ toluene Then 25 9 grams (0 2 mole~) of dibutylamin- was added ov-r tw~nty minutes followed by 20 3 grams (0 2 mole~) o~ triethylamine added over ten minutes The mixture was warmed to 60C and vigorously stirred for thirty minutes T~en the mixture was washed twice with 100 Ml o~ water, follow-d by aqueous potassium carbonate and water again The vessel was th-n s-t up ~or distillation and heated to 140C to remove re~idual water and toluene ~EL~3 Thi~ xampl- illu~trat-d the preparation of the N,N-dipenyl-3,S-dinitrob-nzamide according to Example 29 except that 23 06 grams ~0 1 mol-~) o~ DNBC and 16 52 grams (1 05 equivalents) of dipentylamin- w-r- used This example illustrated the preparation o~ the N-(2-ethylhexyl)-3,5-dinitrobenzamide according to Example 29 except that 2~81~

23 06 grams (0 1 moles) of DNBC and 26 50 grams (2 05 equivalents) o~ 2-ethylh-XYl amine were used This example illustrated the preparation of the N,N-di(2-ethylh-xyl)-3,5-dinitrobenzamide according to Example 29 except that roughly two equivalents o~ di-(2-ethylhexyl) amine was used instead o~ dlbutyl amine Although xamplQ 29-32 are specific example~ of the preparation o~ mark~r~ o~ ~ormula (I) using the general procedure of Example 29, it should b- appreciated that this same techniqu- can b~ applied with equal as- to any other amine listed and generally enumerated in th- ~p-ciricatiOn PB~PA~A~LQN OF MARKER LIQUID COMPOSITION

Thi- xampl- illu~trat~d tho g~nQral pr-paration and analysis ot a liquid hydrocarbon with a marker of th~ pr-~-nt invention In particular, thi~ example depicted the marking o~ isooctane with thr-- marker~ of formula (I) and a mod-l compound o~ ~ormula ~I) The exampl- also d~pict~d th- analysi~ of thQ markQd i~ooctana using a GC with an lectron captur~ d~tector (ECD) To a volum-tric ~la~ wa- added 5 00 grams o~ each o~ the product~ ~rom Exampl-~ 1 (2--thylh-xyl-3,S-dinitrob-nzoate), 9 (2-butoxy-thyl-3,5-dinitrob-nzoat~), 29 (N,N-dibutyl-3,5-dlnltrob-nza~id-), and ~,2-diphanyl ~than~dion- for co~parison The volu~a wa~ ad~u~t-d to 100 mL with toluene and the contents thoroughly mix-d Thon 10 ~1 o~ this solution was added by syringe to 100 mL o~ i~ooctan- Th- isooctano ~olutiGn containing the four lectron-captur~-datection-s~n~itiv~ compound- wa- analyz-d by gas chromatography with a polydimethylsiloxan- capillary column and ECD
The following data wa~ record-d TA~3LE I
~3 ' ' . ', . ' :

~Q~8~ 7~

Retention Relative Markers Time ~min ) Sen~itivity 1~2-diphenyl ethanedionQ 2 06 l oO
2-ethylhexyl-3,5-dinitrobenzoate3 44 0 62 2-butoxyethyl-3,5-dinitrobenzoate 2 78 0 68 N,N-dibutyl-3,5-dinitrobenzamide4 31 1 21 ~
lS This xample illustrat-d the u~e of the marker from Example 29 (N,N-dibutyl-3,5-dinitrobenzamide) to mark commercial gasoline The marker was added to the p-rformance enhancement package and was asily analyz-d according to the procedure in Example 33 1 0 grams o~ N,N-dibutyl-3,5-dinitrobenzamid- was dissolved in a 99 0 gram~ o~ a comm-rcial ga~olin- additiv~ packag- containing a polym-ric doterg-nt, a ~ynthetic carri~r oil and a blend of d-mul~i~ying ag-nt~ The r-sulting packag- wa~ blended into unadditized premium unleaded gasolinQ at a dosage o~ 500 pp-~wt/wt) When analyzed by gas chromatography using the same condition~ as in Exampl~ 33, N,N-dibutyl-3,5-dinitrobenzamide was detected in th~ flat ba~-lin- region of the GC trac~ at 4 3 minutes after in~-ction All oth-r electron captur- detector sensitive component~ o~ th- ga~olin- had passed through the column within three minute~
Although thi~ xample dealt with commercial ga~oline, the mark-d hydrocarbon liquid~, a~ u~Qd in th~ ~peci~ication and in the claim~ int-nd-d to cov-r a wid- variety and type of organic liguid~ Thu~, typical liquid~ that may be marked using the invention ar- such liguid~ as gasolino and ga~oline blending compon-nt~, di~ uols, ~-t ~u-l~, lubricant~, heating oils, residual oil~ re~ulting ~rom th- re~ining o~ petroloum, coal oils and the like 2~

This example illustrated the found retention times of a series o~ 28 of the markers of formula (I) using a polydimethylsiloxane capillary column equipped with a flame ionization detector Although the detector was different than the electron capture detector, the retention times were unaffected being simply the time required for the marker to exit out of the column and to encounter a detector at the column exit To a volumetric flask was added 5 00 grams of each of the ~ollowing markers (Ml-M28) from the following examples Ml is N-(2-ethylhexyl)-3,5-dinitrobenzamide from Example 31;
M2 is N,N-di(2-ethylhexyl)-3,5-dinitrobenzamide from Example 32;
M3 is 2-(2-hexoxyethoxy)ethyl-3,5-dinitrobenzoate from Example 3;
M4 is N,N-dipentyl-3,5-dinitrobenzamide from Example 30;
MS is 2-ethylhexyl-3,S-dinitrobenzoate from Example l;
M6 i~ hexyl-3,5-dinitrobenzoate ~rom Example 12;
M7 is pentyl-3,5-dinitrobenzoate from Example 11;
M8 is 2-octyl-3,5-dinitrobenzoate from Example 22;
M9 is N,N-dibutyl-3,5-dinitrobenzamide from ExampIe 29;
M10 i~ 2-methyl-1-pentyl-3,5-dinitrobenzoate from Example 18;
Mll is 3-m-thyl-1-butyl-3,5-dinitrobenzoate from Example 26;
M12 iJ 4-m-thyl-2-pentyl-3,S-dinitrobenzoate ~rom Example 19;
M13 i8 3,5,5-trim-thyl-1-hexyl-3,5-dinitrobenzoate ~rom Example 23;
M14 is 2-t2-butoxyethoxy)ethyl-3,5-dinitrobenzoate from Example 15;
M15 is 2-methyl-1-butyl-3,5-dinitrobenzoate ~rom Example 25;
M16 is 2-(2-propoxyethoxy)ethyl-3,5-dinitrobenzoate from Example ~;
M17 is 2-(2-methoxyethoxy)ethyl-3,5-dinitrobenzoate from Example 16;
M18 i5 decyl-3,S-dinitrobenzoate from Examples 2 or 14;
M19 is methyl-3,5-dinitrobenzoate from Example 27;
M20 i~ 2-methoxyethyl-3,5-dinitrobenzoate ~rom Example 17;
M21 is 2-ethyl-1-butyl-3,5-d~nitrobenzoate from Example 28;
M22 is 2,4-dimethyl-3-pentyl-3,5-dinitrobenzoate ~rom Example 20;
M23 i~ heptyl-3,5-dinitrobenzoat- from Example 21;
M24 i~ 2-h-xoxy-thyl-3,S-dinitrobenzoatQ ~rom Exampl- 4;
M~S i- 2-propoxy-thyl-3,5-dinitrobenzoate from Example 8;
M26 i~ 3,7-dim-thyl-1-octyl-3,S-dinitrobenzoate from Example 24;
M27 ia 2-butoxy-thyl-3,5-dinitrobenzoate ~rom Example 9;
M28 ia octyl-3,5-dinitrob-nzoate ~rom Example 13 The volume was adju~ted to 100 Ml with xylene and the contents thorouqhly mixed Then 0 4 ~L o~ this solution was injected into the GC at a 1 to 6 split ratio The GC wa~ e~uipped with a 12 meter by 0 53 millimeter polydimethyl~iloxane coated capillary column with l micrometer coating The injector port wa~ 2~5C and column 2~81~3 temp-rature o~ 230OC Under these conditions the following data set of retention times were recorded TABLE II
Retention S Marker Time , M6 4 95 ~7 3 22 ;25 Ml9 1 79 M2~ 4 78 ; M28 6 61 Although th- ~ark-r~ o~ the pre-ent invention have been d-~crib-d h-r-inabo~- in ~om- d-ta$1, it ~hould be appreciated that a vari-ty o~ analogou~ mark-r~ will b- readily apparent from the ~peci~ic ~or~ula~ ncompa-~ed in the sp-ci~ication and claimed in th- claim~ Oth-r marker~ and compo ition~ which incorporate modi~ication and analog- to the mark-r~, compo~ition~ and methods de~crib-d h-reinabov- are equally includ-d within this application :
:

.
.
-~ ' --

Claims (27)

WHAT IS CLAIMED IS

1 A composition comprising a liquid hydrocarbon and one or more marker compounds, said marker being present in sufficient quantity to facilitate subsequent analytical identification and where said marker is a compound of formula (I) where Y is selected from the group consisting of X-R1 and NR2R3, where X is either oxygen or sulfur, where R1 is a organic radical having from about 1 to about 30 carbon atoms, and where R2 and R3 are the same or different organic radical having from about 1 to about 30 carbon atoms.

2 A composition according to claim 1, wherein said marker is a compound of formula (I) where Y is X-R1, where X is oxygen and where R1 is a selected from the group consisting of a hydrogen atom, a linear or branched alkyl having from about 1 to about 30 carbon atoms, an aryl group having from about 6 to about 30 atoms, a cycloaliphatic group having from about 3 to about 30 carbon atoms, a heterocyclic group, a substituted alkyl group, a substituted aryl group, a diol, a polyol, an alkylated or acylated glycol, an alkylated or acylated polyglycol, and alkylated or acylated ethylene polyamine.

3 A composition according to claim 2, wherein said marker is a compound of formula (I) where R1 is selected from the group consisting of a linear or branched alkyl group having from about 1 to about 30 carbon atoms, an alkylated glycol and an alkylated polyglycol.

4 A composition according to claim 3, wherein said marker is a compound of formula (I) where R1 is selected from the group consisting of methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, isopropyl, isobutyl, isopentyl, t-butyl, neopentyl, 2-methyl-1-butyl, 2-ethyl-1-butyl, 2-methyl-1-pentyl, 4-methyl-2-pentyl, 2,4-dimethyl-3-pentyl, 2-ethylhexyl, 3,5,5-trimethyl-1-hexyl, 2-octyl, and 3,7-dimethyl-1-octyl

A composition according to claim 3, wherein said marker is a compound of formula (I) where R1 is selected from the group consisting of 2-(2-methoxyethoxy)ethyl, 2-(2-ethoxyethoxy)ethyl, 2-(2-propoxyethoxy)ethyl, 2-(2-butoxyethoxy)ethyl, (2-pentoxyethoxy)ethyl, 2-(2-hexoxyethoxy)ethyl, 2-methoxyethyl, 2-ethoxyethyl, 2-propoxyethyl, 2-butoxyethyl, 2-pontoxyethyl, 2-hexoxyethyl and 1-methyl-2-propoxyethyl.

6. A composition according to claim 1, wherein said marker is a compound of formula (I) where Y is X-R1, whare X is sulfur and where R1 is selected from the group consisting of a hydrogen atom, a linear or branchod alkyl having from about 1 to about 30 carbon atoms, an aryl group having from about 6 to about 30 atoms, a cycloaliphatic group having from about 3 to about 30 carbon atoms, a heterocyclic group, a substituted alkyl group, a substituted aryl group, a diol, a polyol, an alkylated or acylated glycol, an alkylated or acylated polyglycol, and alkylated or acylated ethylene polyamine

7. A composition according to claim 6, wherein said marker is a compound of formula (I) where R1 is selected from the group consistins of a linear or branched alkyl group having from about 1 to about 30 carbon atoms, an alkylated glycol and an alkylated polyglycol

8. A composition according to claim 7, wherein said marker is a compound of formula (I) where R1 is selected from the group consisting of methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, isopropyl, isobutyl, isopentyl, t-butyl, n-opentyl, 2-methyl-1-butyl, 2-ethyl-1-butyl, 2-methyl-1-pentyl, 4-methyl-2-pentyl, 2,4-dimethyl-3-pentyl, 2-ethylhexyl, 3,5,5-trimethyl-1-hexyl, 2-octyl, and 3,7-dimethyl-1-octyl

9. A composition according to claim 7, wherein said marker is a compound of formula (I) where R1 is selected from the group consisting of 2-(2-methoxyethoxy)ethyl, 2-(2-ethoxyethoxy)ethyl, 2-(2-propoxyethoxy)ethyl, 2-(2-butoxyethoxy)ethyl, (2-pentoxyethoxy)ethyl, 2-(2-hexoxyethoxy)ethyl, 2-methoxyethyl, 2-ethoxyethyl, 2-propoxyethyl, 2-butoxyethyl, 2-pentoxyethyl, 2-hexoxyethyl and 1-methyl-2-propoxyethyl.

10. A composition according to claim 1, wherein said marker is a compound of formula (I) where Y is NR2R3 and where R2 and R3 are the same or different and selected from the group consisting of a hydrogen atom, a linear or branched alkyl having from about 1 to about 30 carbon atoms, an aryl group having from about 6 to about 30 atoms, a cycloaliphatic group having from about 3 to about 30 carbon atoms, a heterocyclic group, a substituted alkyl group, a substituted aryl group, a diol, a polyol, an alkylated or acylated glycol, an alkylated or acylated polyglycol, and alkylated or acylated ethylene polyamine.

11 A composition according to claim 10, wherein said marker is a compound of formula (I) where R2 and R3 are the same or different and selected from the group consisting a linear or branched alkyl group having from about 1 to about 30 carbon atoms, an alkylated glycol and an alkylated polyglycol.

12. A composition according to claim 11, wherein said marker is a compound of formula (I) where R2 and R3 are the same or different and selected from the group consisting of methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, isopropyl, isobutyl, isopentyl, t-butyl, neopentyl, 2-methyl-1-butyl, 2-ethyl-1-butyl, 2-methyl-1-pentyl, 4-methyl-2-pentyl, 2,4-dimethyl-3-pentyl, 2-ethylhexyl, 3,5,5-trimethyl-1-hexyl, 2-octyl, and 3,7-dimethyl-1-octyl.

13. A composition according to claim 1, wherein said marker is present from about 0 5 parts per million to about 25 parts per million.

14. A composition according to claim 13, wherein said marker compound is present in an amount from about 1 part per million to about 10 parts per million.

15. A composition according to claim 1, wherein said liquid hydrocarbon is selected from the group consisting of crude oil, residual oil, lubricating oil, hydraulic and circulating oils, heating oil, diesel fuel and mid-distillates, jet fuel, aviation fuel, gasoline, gasohol or alcohol fuels, polymer lattices and solutions, MTBE (methyl t-butyl ether), and bulk liquid polymers or mixtures thereof.

16. A method for marking a hydrocarbon liquid comprising the steps of adding one or more markers to a liquid hydrocarbon, said marker being present in sufficient quantity to facilitate subsequent analytical identification and quantitation and ranging from about 0.5 ppm to about 50 ppm based on the weight of the liquid hydrocarbon and where said marker is a compound of formula (I) IMP
where Y is selected from the group consisting of X-R1 and NR2 R3, where X is either oxygen or sulfur, where R1 is an organic radical having from about 1 to about 30 carbon atoms, and where R2 and R3 are the same or different organic radical having from about 1 to about 30 carbon atoms.

17. A method according to claim 16, wherein said marker is a compound of formula (I) where Y is X-R1, where X is oxygen and where R1 is a selected from the group consisting of a hydrogen atom, a linear or branched alkyl having from about 1 to about 30 carbon atoms, an aryl group having from about 6 to about 30 atoms, a cycloaliphatic group having from about 3 to about 30 carbon atoms, a heterocyclic group, a substituted alkyl group, a substituted aryl group, a diol, a polyol, an alkylated or acylated glycol, an alkylated or acylated polyglycol, and alkylated or acylated ethylene polyamine.

18. A method according to claim 17, wherein said marker is a compound of formula (I) where R1 is selected from the group consisting of a linear or branched alkyl group having from about 1 to about 30 carbon atoms, an alkylated glycol and an alkylated polyglycol.

19. A method according to claim 16, wherein said marker is a compound of formula (I) where Y is NR2R3 and where R2 and R3 are the same or different and selected from the group consisting of a hydrogen atom, a linear or branched alkyl having from about 1 to about 30 carbon atoms, an aryl group having from about 6 to about 30 atoms, a cycloaliphatic group having from about 3 to about 30 carbon atoms, a heterocyclic group, a substituted alkyl group, a substituted aryl group, a diol, a polyol, an alkylated or acylated glycol, an alkylated or acylated polyglycol, and alkylated or acylated ethylene polyamine.

20. A method according to claim 19, wherein said marker is a compound of formula (I) where R2 and R3 are the same or different and selected from the group consisting a linear or branched alkyl group having from about 1 to about 30 carbon atoms, an alkylated glycol and an alkylated polyglycol.

21. A method according to claim 16, wherein a set of n markers are added to said liquid at M different quantitative values to form a unique tag for said liquid where n is a number having a value from about 2 to about 15 and M is a number of from about 2 to about 10.

22 An analytical method comprising the steps of analyzing a sample of a composition comprising a liquid hydrocarbon and one or more markers by an analytical method sufficient to identify and quantify said markers, said marker being present in sufficient quantity to facilitate subsequent analytical identification and quantitation where said marker is a compound of formula (I):

where Y is selected from the group consisting of X-R1 and NR2 R3, where X is either oxygen or sulfur, where R1 is an organic radical having from about 1 to about 30 carbon atoms and where R2 and R3 are the samo or different organic radical having from about 1 to about 30 carbon atoms.

23. An analytical method according to claim 22 wherein said analytical method is gas chromatoqraphy adapted with an electron capture detector.

24. An analytical method according to claim 23 wherein said gas chromatogram is equipped with a column including a stationary phase selected from the group consisting of dialkylpolysiloxanes, alkylarylpolysiloxane, substituted alkylarylpolysiloxanes, copolymers thereof and mixtures thereof and carbowaxes, where the alkyls have from about 1 to about 10 carbon atoms, the aryls have from about 6 to about 14 carbon atoms, and the substituted alkyls are cyanoalkyls, dialkylaminoalkyls, alkoxyalkyls, and haloalkyls

25. An analytical method according to claim 22 wherein said the material is selected from the group consisting of dimethylpolysiloxane, phenylmethyl polysiloxane and cyanopropylphenyl-methyl polysiloxane.

26. A method according to claim 22, wherein a set of n markers are analyzed at M different quantitative values to determine a unique tag for said liquid where n is a number having a value from about 2 to about 15 and M is a number of from about 2 to about 10.

27. A method for analyzing a liquid composition containing one or more markers comprising the steps of:
1) injecting a liquid composition comprising a liquid hydrocarbon and one or more markers onto a first end of a first GC
column through an injector port equipped with a carrier gas supply;
2) separating said markers from a major portion of said liquid into one or more discrete peaks on said first column;
3) opening a valve connected to a second end of said first column for one or more time windows;
4) collecting each of said markers corresponding to each of said windows into a cold trap comprising a first end of a second GC
cooled by a coolant;
5) removing said coolant from said cold trap;
6) further separating said markers on said second column; and 7) detecting each of said markers with an electron capture detector equipped with a make up gas, said first column containing a first column stationary phase and being of a first length sufficient to affect an initial or partial separation of the marker from said major portion of said liquid, said windows corresponding to one or more retention times of said markers and being of sufficient duration to allow all or nearly all of each marker to pass therethrough, and said second column containing a second column stationary phase being the same or different from said first stationary phase and being of a second length sufficient to separate each of said markers from an other components in said liquid.