US2258249A - Treatment of hydrocarbon distillates - Google Patents
Treatment of hydrocarbon distillates Download PDFInfo
- Publication number
- US2258249A US2258249A US270426A US27042639A US2258249A US 2258249 A US2258249 A US 2258249A US 270426 A US270426 A US 270426A US 27042639 A US27042639 A US 27042639A US 2258249 A US2258249 A US 2258249A
- Authority
- US
- United States
- Prior art keywords
- solution
- sulfur
- distillate
- alkali metal
- sweetening
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000004215 Carbon black (E152) Substances 0.000 title description 7
- 229930195733 hydrocarbon Natural products 0.000 title description 7
- 150000002430 hydrocarbons Chemical class 0.000 title description 7
- 239000000243 solution Substances 0.000 description 22
- 229910052717 sulfur Inorganic materials 0.000 description 21
- 239000011593 sulfur Substances 0.000 description 21
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 20
- 238000000034 method Methods 0.000 description 16
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 12
- LSDPWZHWYPCBBB-UHFFFAOYSA-N Methanethiol Chemical compound SC LSDPWZHWYPCBBB-UHFFFAOYSA-N 0.000 description 11
- 239000003502 gasoline Substances 0.000 description 10
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 8
- 229910052783 alkali metal Inorganic materials 0.000 description 7
- 150000001340 alkali metals Chemical class 0.000 description 7
- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 6
- 238000009835 boiling Methods 0.000 description 6
- 239000000203 mixture Substances 0.000 description 5
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical class S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 4
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 4
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 3
- 125000000217 alkyl group Chemical group 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 235000011187 glycerol Nutrition 0.000 description 3
- 239000005077 polysulfide Substances 0.000 description 3
- 150000008117 polysulfides Polymers 0.000 description 3
- 229910052708 sodium Inorganic materials 0.000 description 3
- 239000011734 sodium Substances 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 239000003125 aqueous solvent Substances 0.000 description 2
- 239000003518 caustics Substances 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 2
- 229940056932 lead sulfide Drugs 0.000 description 2
- 229910052981 lead sulfide Inorganic materials 0.000 description 2
- -1 poly-hydroxy alcohol Chemical compound 0.000 description 2
- 229920001021 polysulfide Polymers 0.000 description 2
- SUVIGLJNEAMWEG-UHFFFAOYSA-N propane-1-thiol Chemical compound CCCS SUVIGLJNEAMWEG-UHFFFAOYSA-N 0.000 description 2
- HYHCSLBZRBJJCH-UHFFFAOYSA-M sodium hydrosulfide Chemical compound [Na+].[SH-] HYHCSLBZRBJJCH-UHFFFAOYSA-M 0.000 description 2
- MRMOZBOQVYRSEM-UHFFFAOYSA-N tetraethyllead Chemical compound CC[Pb](CC)(CC)CC MRMOZBOQVYRSEM-UHFFFAOYSA-N 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical class [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 229910001854 alkali hydroxide Inorganic materials 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- DNJIEGIFACGWOD-UHFFFAOYSA-N ethyl mercaptane Natural products CCS DNJIEGIFACGWOD-UHFFFAOYSA-N 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- HTUMBQDCCIXGCV-UHFFFAOYSA-N lead oxide Chemical compound [O-2].[Pb+2] HTUMBQDCCIXGCV-UHFFFAOYSA-N 0.000 description 1
- YEXPOXQUZXUXJW-UHFFFAOYSA-N lead(II) oxide Inorganic materials [Pb]=O YEXPOXQUZXUXJW-UHFFFAOYSA-N 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229940008718 metallic mercury Drugs 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- TVMXDCGIABBOFY-UHFFFAOYSA-N octane Chemical compound CCCCCCCC TVMXDCGIABBOFY-UHFFFAOYSA-N 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 125000000962 organic group Chemical group 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000003079 shale oil Substances 0.000 description 1
- 229910052979 sodium sulfide Inorganic materials 0.000 description 1
- GRVFOGOEDUUMBP-UHFFFAOYSA-N sodium sulfide (anhydrous) Chemical compound [Na+].[Na+].[S-2] GRVFOGOEDUUMBP-UHFFFAOYSA-N 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 125000004434 sulfur atom Chemical group 0.000 description 1
- 239000011269 tar Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
- C10G19/00—Refining hydrocarbon oils in the absence of hydrogen, by alkaline treatment
- C10G19/02—Refining hydrocarbon oils in the absence of hydrogen, by alkaline treatment with aqueous alkaline solutions
- C10G19/06—Refining hydrocarbon oils in the absence of hydrogen, by alkaline treatment with aqueous alkaline solutions with plumbites or plumbates
Definitions
- This: invention concerns a method for treating hydrocarbon distillates and more particularly',.a method for sweetening suchdistillates and removing the elementary sulfur therefrom.
- distillates treated according to the present process ar of petroleum origin and of motor fuel boiling range.
- sour distillates of higher than gasoline boiling range, and from other hydrocarbon sources such.as;:for example, shale oils, coal tars, etc, may also "be treated according to the invention.
- hydrocarbon distillates such as gasoline in particular, generally require sweetening in order to improve the odorand likewiseto eliminate possible corrosive properties.
- sweetening methods which have been used for this purpose is the so-called sodium plumbite ordoctor process wherein distillate is contacted with a solution of litharge in sodium hydroxide, followed by the addition of elementary sulfur to bring about decomposition of the lead mercaptides to alkyl diand poly-sulfides and lead sulfide. In order to obtain a good break, i.
- the presentinvention comprises sweetening hydrocarbon distillate by means of doctor solution and amounts of elementary sulfur in excess of that required to decompose the lead mercaptides, separating the sweetened distillate, contacting it with a solution of an alkali metal hydroxide containing a lowboiling mercaptan in amount equal to 1 to 10-mol per cent of the sodium hydroxide present, separating the distillate, and washing it with a solution of an alkali metal hydroxide.
- the excess free sulfur is removed from the distillate by means of th solution of alkali metal mercaptide.
- the solution contains sufficient low-boiling mercaptan, preferably ethyl, methyl, or propyl mercaptan, to react with from i to 10 per cent of the alkali metal hydroxide present in the solution, and ordinarily the amount of mercaptan is of the order of 2.5 and 5 mol per cent of the caustic present.
- mercaptans or higher molecular weight mercaptans there is a tendency for part of the mercaptan to pass into the distillate because of hydrolysis of the alkali metal mercaptide.
- alkali metal mercaptide solution of sufficient dilution that none of the mercaptan is extracted by the distillate and/or use a final wash with alkali hydroxide solution.
- sodium hydroxide is the alkali metal hydroxide used although potassium and lithium hydroxides are also useful.
- free sulfur as used herein is not inmethod, and the so-called copper sweetening" method, neither of which employ elementarysulfur or effect its removal from distillates during sweetening. In these cases as in those mentioned, the sulfur is removed by treating the sweetened gasoline with a solution ofv alkali metal mercaptide in a solution of an alkali metal hy droxide.
- the process is carried out at any temperature suitable for. the sodium plumbite sweetening method.v This is normally atmospheric temperature, although in certain cases temperatures up to 150 F. have been employed and in some instances, lowered temperatures have been used.
- non-aqueous or mixed non-aqueous solvents or mixtures of water and non-aqueous solvents may be used.
- solvents may be selected from the group consisting of a monoorpoly-hydroxy alcohol, a mixture of a monoand a poly-hydroxy alcohol, a glycol, a mixture of a glycol and a mono-hydroxy alcohol, glycerine, a mixture of glycerine and a mono-hydroxy alcohol, and a mixture of a mono-hydroxy alcohol with glycerine and minor amounts of water.
- the final treatment with an alkali metal hydroxide solution is not a special feature of the .present invention and can be dispensed with in certain cases.
- the step is used as an added safeguard, since in certain instances if the mercaptide concentration of the sulfur removing solution were too high, the resulting gasoline might possibly be slightly sour and this is corrected by the caustic wash. Likewise small portions of the sodium mercaptide solution may be entrained whereby the free sulfur was reduced to less than 0.001%; The color dropped on exposure to sunlight from 30+ to 28, while the sample before sulfur'removal dropped from 30+ to 17 and became hazy.
- the gasoline was Washed with a 10% solution of sodium hydroxide following the treatment with the sodium mercaptide solution.
- a process for sweetening hydrocarbon dis tillates containing mercaptans which comprises treating the distillate with sodium plumbite solu- 3 tion and a quantity of elementary sulfur inexcess of that required to convert the mercaptans to lead mercaptides, then treating the distillate with a solution of an alkali metal hydroxide containing a relatively small amount of a low-boiling mercaptan, the last-named solution being in suflicient amount to remove the excess sulfur from the distillate, and thereafter recovering the distillate without further plumbite treatment.
Landscapes
- Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
Description
Patented Oct. 7, 1941 Warren W. Johnstone, Chicago,-. Ill,., assignor to Universal Oil Products Company, Chicago, 111., a corporation ofDelaware No Drawing.
Application April 27, 1939,
Serial No. 270,426
4 Claims.
This: invention concerns a method for treating hydrocarbon distillates and more particularly',.a method for sweetening suchdistillates and removing the elementary sulfur therefrom.
'Usually the distillates treated according to the present process ar of petroleum origin and of motor fuel boiling range. However, sour distillates of higher than gasoline boiling range, and from other hydrocarbon sources such.as;:for example, shale oils, coal tars, etc, may also "be treated according to the invention.
; Practically all hydrocarbon distillates require some form of treatment in order to yield marketable products. Light hydrocarbon distillates such as gasoline in particular, generally require sweetening in order to improve the odorand likewiseto eliminate possible corrosive properties. Among the sweetening methods which have been used for this purpose is the so-called sodium plumbite ordoctor process wherein distillate is contacted with a solution of litharge in sodium hydroxide, followed by the addition of elementary sulfur to bring about decomposition of the lead mercaptides to alkyl diand poly-sulfides and lead sulfide. In order to obtain a good break, i. e., separation of lead sulfide from the distillate, it is usually necessary to add an excess of elementary sulfur over that required theoretically to accomplish the actual sweetening reaction. Various methods have been proposed for reducing the amount of elementary sulfur necessary, but in the majority of cases doctor sweetened distillate contains so-called free-sulfur in solution. When sweetening gasoline it is known that considerable excess sulfur can be added at the time of doctor sweetening without producing a corrosive gasoline. This may sometimes amount to as much as 0.02% without showing a positive corrosion test. Nevertheless, the other desirable properties of both cracked and straight-run gasolines may suffer materially, for example, the color stability, octane number, and susceptibility to tetraethyl lead may be markedly reduced. In the case of cracked gasolines the copper dish gums may be increased, the storage stability as indicated. by the oxygen bomb induction period may be shortened and susceptibility to stabilization by means of gum inhibitors may be markedly decreased.
Various methods have been practiced for removing the excess free sulfur from gasoline and other distillates thereby improving the quality of the sweetened product. In cases where the sweetened gasoline is actually corrosive, it has sometimes been the practice to mix it with the sour gasoline and return it to the sweetening operation and then use greater care in the addition of sulfur. This particular method, however, is of no great importance except in the case vofacorrosive gasolines, since it does not eliminate thenecessityfor adding excess sulfur dur ing the process to obtain a good break or provide a means for removing the sulfur substantially completely. The use of alkali metal polysulfides and metallic mercury has been practiced for this purpose.
In one specific embodiment the presentinvention comprises sweetening hydrocarbon distillate by means of doctor solution and amounts of elementary sulfur in excess of that required to decompose the lead mercaptides, separating the sweetened distillate, contacting it with a solution of an alkali metal hydroxide containing a lowboiling mercaptan in amount equal to 1 to 10-mol per cent of the sodium hydroxide present, separating the distillate, and washing it with a solution of an alkali metal hydroxide.
The excess free sulfur is removed from the distillate by means of th solution of alkali metal mercaptide. Usually the solution contains sufficient low-boiling mercaptan, preferably ethyl, methyl, or propyl mercaptan, to react with from i to 10 per cent of the alkali metal hydroxide present in the solution, and ordinarily the amount of mercaptan is of the order of 2.5 and 5 mol per cent of the caustic present. When larger amounts of mercaptans or higher molecular weight mercaptans are used, there is a tendency for part of the mercaptan to pass into the distillate because of hydrolysis of the alkali metal mercaptide. It is preferred to use an alkali metal mercaptide solution of sufficient dilution that none of the mercaptan is extracted by the distillate and/or use a final wash with alkali hydroxide solution. Ordinarily sodium hydroxide is the alkali metal hydroxide used although potassium and lithium hydroxides are also useful.
The reactions involved in elimination of the free sulfur are not entirely known but are possibly of the type 2(R-SNa) +S- R2S2+Na2S 2n (RSN%L) +R'2S2+n nR2S2+R'2Sz-HtNa2S The latter equation represents a possible reaction when the sulfur is in the form of alkyl polysulfides containing 2+n sulfur atoms per molecule. R and R represent organic groups such as alkyl or aryl groups.
The term free sulfur as used herein is not inmethod, and the so-called copper sweetening" method, neither of which employ elementarysulfur or effect its removal from distillates during sweetening. In these cases as in those mentioned, the sulfur is removed by treating the sweetened gasoline with a solution ofv alkali metal mercaptide in a solution of an alkali metal hy droxide.
The process is carried out at any temperature suitable for. the sodium plumbite sweetening method.v This is normally atmospheric temperature, although in certain cases temperatures up to 150 F. have been employed and in some instances, lowered temperatures have been used.
Although the alkaline solution of mercaptide is usually used in aqueous solution, under certain circumstances non-aqueous or mixed non-aqueous solvents, or mixtures of water and non-aqueous solvents may be used. Such solvents may be selected from the group consisting of a monoorpoly-hydroxy alcohol, a mixture of a monoand a poly-hydroxy alcohol, a glycol, a mixture of a glycol and a mono-hydroxy alcohol, glycerine, a mixture of glycerine and a mono-hydroxy alcohol, and a mixture of a mono-hydroxy alcohol with glycerine and minor amounts of water. I The final treatment with an alkali metal hydroxide solution is not a special feature of the .present invention and can be dispensed with in certain cases. The step is used as an added safeguard, since in certain instances if the mercaptide concentration of the sulfur removing solution were too high, the resulting gasoline might possibly be slightly sour and this is corrected by the caustic wash. Likewise small portions of the sodium mercaptide solution may be entrained whereby the free sulfur was reduced to less than 0.001%; The color dropped on exposure to sunlight from 30+ to 28, while the sample before sulfur'removal dropped from 30+ to 17 and became hazy.
In this example the gasoline was Washed with a 10% solution of sodium hydroxide following the treatment with the sodium mercaptide solution.
I claim as my invention:
1. A process for sweetening hydrocarbon dis tillates containing mercaptans which comprises treating the distillate with sodium plumbite solu- 3 tion and a quantity of elementary sulfur inexcess of that required to convert the mercaptans to lead mercaptides, then treating the distillate with a solution of an alkali metal hydroxide containing a relatively small amount of a low-boiling mercaptan, the last-named solution being in suflicient amount to remove the excess sulfur from the distillate, and thereafter recovering the distillate without further plumbite treatment.
' 2. The process as defined in claim 1 further characterized in that the distillate, following the second-mentioned treatment, is washed with alkali metal hydroxide solution.
3. The process as defined in claim 1 further characterized in that the amount of low-boiling mercaptan in the second-mentioned solution is from 1 to 10 mol per cent of the alkali metal hy-i droxide present in the solution.
4. The process as defined in claim 1 further characterized in that said low-boiling mercaptan comprises methyl mercaptan.
WARREN W. J OI-INSTONE,
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US270426A US2258249A (en) | 1939-04-27 | 1939-04-27 | Treatment of hydrocarbon distillates |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US270426A US2258249A (en) | 1939-04-27 | 1939-04-27 | Treatment of hydrocarbon distillates |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2258249A true US2258249A (en) | 1941-10-07 |
Family
ID=23031281
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US270426A Expired - Lifetime US2258249A (en) | 1939-04-27 | 1939-04-27 | Treatment of hydrocarbon distillates |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2258249A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2771405A (en) * | 1954-03-12 | 1956-11-20 | Standard Oil Co | Reduction of copper corrosivity of sweet oils |
-
1939
- 1939-04-27 US US270426A patent/US2258249A/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2771405A (en) * | 1954-03-12 | 1956-11-20 | Standard Oil Co | Reduction of copper corrosivity of sweet oils |
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