Methods and compounds for removing non-acidic contaminants from hydrocarbon streams
10822549 ยท 2020-11-03
Assignee
Inventors
- Paul J. Biggerstaff (Sugar Land, TX, US)
- Jerry J. Weers (Richmond, TX)
- Sai Reddy Pinappu (Houston, TX, US)
- Weldon J. Cappel (Tomball, TX, US)
Cpc classification
B01D2252/20473
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
An extraction solvent comprised of one or more ethyleneamines having structure (I), (II), or (III): ##STR00001##
where R.sub.1-R.sub.6 can independently be H, C.sub.1-C.sub.4 linear or branched alkyl, amido (RRNCO), or hydroxyalkyl, where each R in the amido group independently H or C.sub.1 alkyl, and where x ranges from 1 to 6, may be contacted with a hydrocarbon stream to remove or extract non-acidic contaminants, such as thiophenes, benzothiophenes, alkyl sulfides, alkyl disulfides, mercaptans, aromatics, oxygenates, metals, olefins, and combinations thereof, from the hydrocarbon stream. The extraction solvent may include co-solvents and the hydrocarbon stream may be in gas and/or liquid form.
Claims
1. A process for removal of non-acidic contaminants from a hydrocarbon stream comprising the contaminants, the process comprising: contacting the hydrocarbon stream containing non-acidic contaminants selected from a group consisting of thiophenes, benzothiophenes, alkyl sulfides, alkyl disulfides, mercaptans, aromatics, oxygenates, metals, olefins, and combinations thereof with an extraction solvent comprising one or more ethyleneamines having structure (I), (II), or (III): ##STR00008## where R.sub.1 is H, R.sub.2-R.sub.6 is, to the extent chemically possible, independently H, C.sub.1-C.sub.4 linear or branched alkyl, amido (RRNCO), or hydroxyalkyl, where each R in the amido group is independently H or C.sub.1 alkyl, and where x ranges from 1 to 6; and upon contacting the hydrocarbon stream with the extraction solvent, a portion of the non-acidic contaminants are removed from the hydrocarbon stream.
2. The process of claim 1, wherein the ratio of the one or more ethyleneamines to hydrocarbon in the hydrocarbon stream ranges from about 1:10 to about 95:100.
3. The process of claim 1, wherein the extraction solvent comprises triethylenetriamine or diethylenetriamine.
4. The process of claim 1, wherein the extraction solvent further comprises a co-solvent selected from a group consisting of water, an alcohol, a glycol, an amide, an ester, an amine different from the ethyleneamine, a quaternary ammonium compound, and combinations thereof.
5. The process of claim 1, wherein the hydrocarbon stream is selected from the group consisting of a gas stream, a liquid stream, and combinations thereof.
6. The process of claim 1, wherein the contacting is achieved by an extraction process having a counter-flow design between the hydrocarbon stream and the extraction solvent.
7. The process of claim 1, wherein the contacting is achieved by injecting the extraction solvent directly into the hydrocarbon stream.
8. The process claim 1, further comprising creating an immiscible two-phase liquid comprising a contaminant-laden extraction solvent stream and a hydrocarbon stream having a reduced amount of non-acidic contaminants after the hydrocarbon stream is contacted with the extraction solvent.
9. The process of claim 8, wherein the contaminant-laden extraction solvent stream is separated from the hydrocarbon stream having a reduced amount of non-acidic contaminants using a separation mechanism selected from the group consisting of a knockout drum, a centrifuge, an absorbent material, and combinations thereof thereby giving a separated contaminant-laden extraction solvent stream.
10. The process of claim 9, further comprising regenerating the separated contaminant-laden extraction solvent stream by passing the contaminant-laden extraction solvent stream through selective filtration media or additional adsorption material thereby removing the contaminants.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1)
DETAILED DESCRIPTION
(2) It has been discovered that contacting a hydrocarbon stream containing non-acidic contaminants with an effective amount of an extraction solvent comprising ethyleneamines of a certain structure is useful or effective for removing the non-acidic contaminants from the hydrocarbon stream.
(3) In one embodiment, the extraction solvent useful for contaminant removal may comprise one or more ethyleneamines having the following general structure:
R.sub.1R.sub.2N(R.sub.3NR.sub.4)NR.sub.5R.sub.6(I)
where R.sub.1-R.sub.6 can independently be H, C.sub.1-C.sub.4 linear or branched alkyl, amido (RRNCO), or hydroxyalkyl, and where each R in the amido group is independently H or C.sub.1 alkyl. Non-exclusive examples of useful and effective extraction solvents falling under this formula are diethylenediamine, diethylenetriamine (DETA), and triethylenetriamine (TETA).
(4) In another non-limiting embodiment, the one or more ethyleneamines to be used in the extraction solvent may have the following structure (II):
(5) ##STR00004##
where R.sub.1-R.sub.4 can independently be H, C.sub.1-C.sub.4 linear or branched alkyl, amido (RRNCO), or hydroxyalkyl, and where each R in the amido group is independently H or C.sub.1 alkyl.
(6) The one or more ethyleneamines may also have the following structure (III):
(7) ##STR00005##
where R-R.sub.5 can independently be H, C.sub.1-C.sub.4 linear or branched alkyl, amido (RRNCO), or hydroxyalkyl, where each R in the amido group is independently H or C.sub.1 alkyl, and where x ranges from 1 to 6.
(8) It is understood that the choice of R groups is made with the goal of optimizing the immiscibility or insolubility of the extraction solvent with hydrocarbon stream being treated in order to facilitate separation of the contaminant-laden extractive solvent stream from the hydrocarbon stream after they are contacted or mixed.
(9) The extraction solvent may further comprise a co-solvent that is compatible with the one or more ethyleneamines described above and that is substantially insoluble in the hydrocarbon stream. Non-limiting examples of co-solvents that may meet this criteria include, but are not limited to, water, alcohols, glycols, amides, ester, amines, quaternary ammonium compounds, carbonates, ketones and combinations thereof.
(10) The hydrocarbon stream to be treated with an extraction solvent comprised of one or more ethyleneamines of the kinds described above may be any industrial hydrocarbon stream, in liquid and/or gas form, that contains non-acidic contaminants. Such streams include, but are not limited to, refinery feedstock, particularly light petroleum gases (LPG), such as (iso)butane and (iso)propane, straight run distillates, cracked stocks, hydrotreated materials, and/or finished fuel blends. The hydrocarbon stream may contain from about 1 ppm to about 10,000 ppm of water, more typically from about 50 ppm to about 1,000 ppm of water.
(11) The removal of the non-acidic contaminants from the hydrocarbon stream using the extraction solvent of the kind described herein may be accomplished, in one non-limiting embodiment, by the liquid-liquid extraction process shown in
(12) In a further process step, the contaminant-laden extraction solvent stream may be separated from the hydrocarbon stream having a reduced amount of non-acidic contaminants using a knockout drum, a centrifuge, and/or an absorbent material and the separated contaminant-laden extraction solvent stream may be regenerated by passing the contaminant-laden extraction solvent stream through selective filtration media or more adsorption material to remove the contaminants.
(13) The non-acidic contaminants present in the hydrocarbon stream may be sulfur compounds, such as, without limitation, thiophenes, benzothiophenes, alkyl sulfides, alkyl disulfides, carbonyl sulfide (COS), carbon disulfide (CS.sub.2), and combinations thereof. The non-acidic contaminants to be removed using the extraction solvent may also include, without limitation, mercaptans, aromatics, oxygenates, metals, olefins, and combinations thereof. In one non-limiting embodiment, mercaptans that may be removed by this method include, but are not necessarily limited to, straight chained or branched, primary, secondary or tertiary mercaptans with a carbon range of C.sub.1-C.sub.5. In another non-restrictive version, aromatics, including substituted and fused-ring aromatics that may be removed by this method include, but are not necessarily limited to, benzene, toluene, naphthalene, and anthracene. In a different non-limiting embodiment, oxygenates that may be removed by this method include, but are not necessarily limited to, straight chained or branched, primary, secondary, tertiary alcohols, and ethers. Further, metals that may be removed by this method include, but are not necessarily limited to, organics, including iron and chlorine, and inorganics, such as chlorides and FeS. Additionally, olefins that may be removed by this method include, but are not necessarily limited to, straight chained or branched, mono, di or poly olefins.
(14) In one embodiment, the ratio of the amount of one or more ethyleneamines to the amount of hydrocarbon in the hydrocarbon stream may range from about 1:10 independently to about 95:100 independently, or from about 25:100 independently to about 75:100 independently, or may be about 50:50. For purposes of this disclosure, the term independently with respect to a range means that any threshold may be used together with any other threshold to form an acceptable alternative range
(15) In another exemplary embodiment, the ratio of the amount of one or more ethyleneamines to the amount of co-solvent in the extraction solvent may range from about 100:0.00001 independently to about 25:75 independently, or may be about 90:10.
(16) A goal of the contacting the extraction solvent with the hydrocarbon stream containing non-acidic contaminants is to reduce the amount of contaminants to an acceptable environmental level. Complete removal of the contaminants from the hydrocarbon stream is desirable, but it should be appreciated that complete removal is not necessary for the methods and compounds discussed herein to be considered effective. Success is obtained if more contaminants are removed from the hydrocarbon stream using the extraction solvent described herein than in the absence of an effective amount of the extraction solvent, and particularly if the contaminants are reduced to an acceptable environmental level.
(17) The invention will be further described with respect to the following Examples, which are not meant to limit the invention, but rather to further illustrate the various embodiments.
EXAMPLES
(18) In one set of evaluations, samples of model hydrocarbons were prepared by adding known amounts of specific types of sulfur compounds. A mixture 40 mL of the model hydrocarbon and 40 mL of the extraction solvent was agitated for 5 minutes and then centrifuged at 1500 rpm for 15 minutes to separate the oil/water phases. A small sample of the hydrocarbon phase was then taken from the container and analyzed for total sulfur content using a XOS Sindie model 2622 10 sulfur analyzer via ASTM D7059. Sulfur reduction, as a percentage, was calculated using the following equation:
[(ppm sulfur in the untreated fuel)(ppm sulfur in treated fuel)/(ppm sulfur in untreated fuel)]100
(19) In another set of evaluations, using the same testing method as set forth above, a few clean hydrocarbon (pentane, gasoline, kerosene, or ultra-low sulfur kerosene (ULSK)) samples were spiked with known amounts of specific sulfur compounds to understand which chemistries worked best in removing which sulfur compounds. These real field samples had a ratio of hydrocarbon to extraction solvent of 1:1.
(20) The results of the evaluations of performance of the various extraction solvents contacted with the hydrocarbon samples is shown below in Tables 1-8. In the Tables, RSH stands for mercaptan, and thiophenes represent a mixture of 100 ppm each of tetrahydrothiophene, thiophene, and 2-methylthiophene.
(21) The data in these Tables show that, in most instances, TETA and DETA do a better job of removing or reducing the amount of most of the sulfur compounds in these various hydrocarbon streams than most of the other extraction solvents tested.
(22) TABLE-US-00001 TABLE 1 Comparing Reduction of Certain Sulfur Compounds in Model Hydrocarbons Using Various Extraction Solvents Sulfur Sulfur % Sulfur Extraction Solvent Compounds ppm Reduction Blank Dimethylsulfide (DMS) 177, 186 Diethylenetriamine (DETA) Dimethylsulfide (DMS) 76 55% 2-Pyrrolidone Dimethylsulfide (DMS) 92 45% Fe dibutylamine 1:1 ratio Dimethylsulfide (DMS) 112 38% NaBH4 (20%) + EDA Dimethylsulfide (DMS) 113 37% EXALT 1100 + EDA Dimethylsulfide (DMS) 141 22% Methanol/water 20/20ml Dimethylsulfide (DMS) 163 9% Y17BH12119 (100 + MeOH) Dimethylsulfide (DMS) 171 8% Y18BH12130 (Quat) Dimethylsulfide (DMS) 179 4% 65% EXALT 1100 Dimethylsulfide (DMS) 184 1% EXALT 1100 Dimethylsulfide (DMS) 186 0% Blank DMS, DMDS, Ethyl RSH 285, 262, 275 2-Pyrrolidone DMS, DMDS, Ethyl RSH 106 63% Diethylenetriamine (DETA) DMS, DMDS, Ethyl RSH 112.1 61% Triethylentetraamine (TETA) DMS, DMDS, Ethyl RSH 111 60% NaBH4/NMP DMS, DMDS, Ethyl RSH 158 43% NaBH4 (6.5%)/DETA DMS, DMDS, Ethyl RSH 151.48 42% Ethylamine DMS, DMDS, Ethyl RSH 165.7 42% Monoethanolamine (MEA) DMS, DMDS, Ethyl RSH 195.4 31% NaBH4 (17%)/Ethylamine DMS, DMDS, Ethyl RSH 197 28% Quaternary Ammonium DMS, DMDS, Ethyl RSH 226 21% Hydroxide Caustic/Glycerol/H2O DMS, DMDS, Ethyl RSH 223 19% Quat/2-Pyrrolidone DMS, DMDS, Ethyl RSH 217.67 17% NaBH4 (6.5%)/MEA DMS, DMDS, Ethyl RSH 221.36 16% Caustic DMS, DMDS, Ethyl RSH 0%, 13% Liquid Ammonia DMS, DMDS, Ethyl RSH 264.1 7% Glycerine DMS, DMDS, Ethyl RSH 275.5 3%
(23) TABLE-US-00002 TABLE 2 Comparing Reduction of Certain Sulfur Compounds from Gasoline, Pentane, and Kerosene Using Caustic, Pyrrolidone, Quaternary Ammonium Hydroxide, DETA, and TETA % Sulfur Reduction Sulfur Content Quaternary Hydrocarbon Sulfur Blank, Pyrollidone Ammonium Stream Compounds ppm-v Caustic (NMP) Hydroxide DETA TETA Refinery Ethyl Mercaptan 188 23% 57% 43% 69% Gasoline Refinery Dimethylsulfide 177, 186 0 45% 4% 55% 70% Gasoline (DMS) Refinery Thiophenes 223 0% 50% 2% 43% 63% Gasoline Refinery Carbon 207, 213 4% 42% 8% 88% 83% Gasoline Disulfuide (CS2) Refinery Butyl Mercaptan 114, 117 2% 36% 9% 54% Gasoline Natural Various 468, 448 13% 33% 17% 40% Gasoline Natural Various 484 30% 37% 37% 39% Gasoline Pentane Dimethylsulfide 89 0% 53% 4% 54% (DMS) Pentane Dimethyldisulfide 133 0% 59% 6% 57% (DMDS) Pentane CS2 227 0% 30% 3% 99% Pentane Ethyl Mercaptan 59 99% 55% 99% 63% Pentane Butyl Mercaptan 53 66% 32% 99% 54% Pentane DMS, DMDS, 49 20% 65% 76% CS2, Ethyl RSH Kerosene Dimethylsulfide 55.5 12% 58% 15% 89% 65% (DMS) Kerosene Dimethyldisulfide 91.6 1% 59% 3% 69% 62% (DMDS) Kerosene CS2 128.79 3% 44% 7% 99% 65% Kerosene Ethyl Mercaptan 53.4 93% 55% 93% 67% Kerosene Thiophenes 140.59 1% 56% 3% 67% 68% Kerosene Various 454.7 12% 51% 17% 70%
(24) TABLE-US-00003 TABLE 3 Comparing Reduction of Thiophenes from Refinery B Gasoline Using Various Extraction Solvents Sulfur Sulfur Content, % Sulfur Sample Compounds ppm Reduction Refinery B Gasoline Blank Thiophenes 223 Refinery B Gasoline w/Na 228 0% Borohydride Refinery B w/50% Na 216 3% Borohydride (in Methanol) Refinery B Gasoline w/Quaternary 219 2% Ammonium Hydroxide Refinery B Gasoline w/DETA 120 43% Refinery B Gasoline w/2- 79 65% Pyrollidone
(25) TABLE-US-00004 TABLE 4 Comparing Reduction of Various Sulfur Compounds from Refinery M ULSK Using Various Extraction Solvents Sulfur Sulfur Content, % Sulfur Sample Compounds ppm Reduction Refinery M ULSK Baseline Various 675 Refinery M ULSK w/50% Na compounds 670 1% Borohydride Refinery M ULSK w/Quaternary 664 2.0% Ammonium Hydroxide Refinery M ULSK w/90/10 327 52% NMP/H2O Refinery M ULSK w/DETA 320 52%
(26) TABLE-US-00005 TABLE 5 Comparing Reduction of Benzothiophenes and Dibenzothiophenes from Refinery A Diesel Using Various Extraction Solvents Sulfur Sulfur Content, % Sulfur Sample Compounds ppm Reduction Refinery A Diesel Baseline Benzothiophenes, 249.48 Refinery A Diesel w/50% Dibenzothiophenes 246.79 1% Na Borohydride Refinery A Diesel w/ 244.23 2% Quaternary Ammonium Hydroxide Refinery A Diesel w/90/ 197.16 21% 10 NMP/H2O Refinery A Diesel w/DETA 204.94 18%
(27) TABLE-US-00006 TABLE 6 Comparing Reduction of Various Sulfur Compounds from Terminal C Natural Gas Using Various Extraction Solvents Sulfur Sulfur Content, % Sulfur Sample Compounds ppm Reduction Terminal C Natural Gas Baseline Various 139.28 Terminal C Natural Gas w/50% Na compounds 118 16% Borohydride Terminal C Natural Gas w/50% Na 117 15% Borohydride (Buyout) Terminal C Natural Gas w/ 98.77 29% Quaternary Ammonium Hydroxide Terminal C Natural Gas w/90/10 84.98 39% NMP/H2O Terminal C Natural Gas w/DETA 79.76 43%
(28) TABLE-US-00007 TABLE 7 Comparing Reduction of Various Sulfur Compounds from Terminal C Cat Naphtha Using Various Extraction Solvents Sulfur Sulfur Content, % Sulfur Sample Compounds ppm Reduction Terminal C Cat Naphtha Baseline Various 222 Terminal C Cat Naphtha w/50% compounds 209 6% Na Borohydride Terminal C Cat Naphtha w/ 204 8% Quaternary Ammonium Hydroxide Terminal C Cat Naphtha w/ 104 53% 90/10 NMP/H2O Terminal C Cat Naphtha w/ 109 51% DETA
(29) TABLE-US-00008 TABLE 8 Comparing Reduction of Various Sulfur Compounds from Terminal P Gasoline Using Various Extraction Solvents Sulfur Sulfur Content, % Sulfur Sample Compounds ppm Reduction Terminal P Gasoline Baseline Thiophenes, 448 Terminal P Gasoline w/50% Diethyl Sulfides, 367 18 Na Borohydride (In Methanol) Isopropyl RSH, Terminal P Gasoline w/ Methyl Ethyl 370 17 Quaternary Ammonium RSH, Dimethyl Hydroxide Disulfides, Terminal P Gasoline with Isobutyl RSH 376 16 65% Na Borohydride (in water) Terminal P Gasoline w/Na 389 13 Borohydride Terminal P Gasoline Blank 468 Retest Terminal P Gasoline w/DETA 289, 279 40 Terminal P Gasoline w/2- 294 37 Pyrrolidone
(30) In the foregoing specification, the invention has been described with reference to specific embodiments thereof. However, the specification is to be regarded in an illustrative rather than a restrictive sense. For example, hydrocarbon streams, ethyleneamines, co-solvents, contaminants, contact/extraction processes, and separation mechanisms falling within the claimed or disclosed parameters, but not specifically identified or tried in a particular example, are expected to be within the scope of this invention.
(31) The present invention may be practiced in the absence of an element not disclosed. In addition, the present invention may suitably comprise, consist or consist essentially of the elements disclosed. For instance, the process may comprise, consist of, or consist essentially of contacting a hydrocarbon stream containing non-acidic contaminants with an extraction solvent consisting essentially of or consisting of one or more ethyleneamines having structure (I), (II), or (III):
(32) ##STR00006##
where R.sub.1-R.sub.6 can independently be H, C.sub.1-C.sub.4 linear or branched alkyl, amido (RRNCO), or hydroxyalkyl, where each R in the amido group is independently H or C.sub.1 alkyl, and where x ranges from 1 to 6.
(33) Alternatively, the treated fluid may comprise, consist of, or consist essentially of a hydrocarbon stream containing non-acidic contaminants; and an extraction solvent consisting of or consisting essentially of one or more ethyleneamines having structure (I), (II), or (III):
(34) ##STR00007##
where R-R.sub.6 can independently be H, C.sub.1-C.sub.4 linear or branched alkyl, amido (RRNCO), or hydroxyalkyl, where each R in the amido group is independently H or C.sub.1 alkyl, and where x ranges from 1 to 6.
(35) The words comprising and comprises as used throughout the claims, are to be interpreted to mean including but not limited to and includes but not limited to, respectively.
(36) As used herein, the word substantially shall mean being largely but not wholly that which is specified.
(37) As used herein, the singular forms a, an, and the are intended to include the plural forms as well, unless the context clearly indicates otherwise.
(38) As used herein, the term about in reference to a given parameter is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the given parameter).
(39) As used herein, the term and/or includes any and all combinations of one or more of the associated listed items.