US2200711A - Process for the refining of naphthenic acids - Google Patents
Process for the refining of naphthenic acids Download PDFInfo
- Publication number
- US2200711A US2200711A US286238A US28623839A US2200711A US 2200711 A US2200711 A US 2200711A US 286238 A US286238 A US 286238A US 28623839 A US28623839 A US 28623839A US 2200711 A US2200711 A US 2200711A
- Authority
- US
- United States
- Prior art keywords
- acids
- naphthenic
- sulfur compounds
- naphthenic acids
- aqueous
- 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
- 125000005608 naphthenic acid group Chemical group 0.000 title description 34
- 238000000034 method Methods 0.000 title description 11
- 238000007670 refining Methods 0.000 title description 8
- 239000002253 acid Substances 0.000 description 21
- 150000007513 acids Chemical class 0.000 description 18
- 150000003464 sulfur compounds Chemical class 0.000 description 18
- HNNQYHFROJDYHQ-UHFFFAOYSA-N 3-(4-ethylcyclohexyl)propanoic acid 3-(3-ethylcyclopentyl)propanoic acid Chemical compound CCC1CCC(CCC(O)=O)C1.CCC1CCC(CCC(O)=O)CC1 HNNQYHFROJDYHQ-UHFFFAOYSA-N 0.000 description 14
- 239000008149 soap solution Substances 0.000 description 14
- 238000010438 heat treatment Methods 0.000 description 12
- 230000002378 acidificating effect Effects 0.000 description 11
- 239000003921 oil Substances 0.000 description 10
- 239000007788 liquid Substances 0.000 description 9
- 230000007935 neutral effect Effects 0.000 description 9
- 239000003518 caustics Substances 0.000 description 8
- 150000002898 organic sulfur compounds Chemical class 0.000 description 8
- 239000012535 impurity Substances 0.000 description 7
- 150000003839 salts Chemical class 0.000 description 7
- 239000003513 alkali Substances 0.000 description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 238000000354 decomposition reaction Methods 0.000 description 3
- 238000004821 distillation Methods 0.000 description 3
- 229910001385 heavy metal Inorganic materials 0.000 description 3
- 239000003209 petroleum derivative Substances 0.000 description 3
- 238000000926 separation method Methods 0.000 description 3
- 239000000344 soap Substances 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- 229910052717 sulfur Inorganic materials 0.000 description 3
- 239000011593 sulfur Substances 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 239000012670 alkaline solution Substances 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 229910052500 inorganic mineral Inorganic materials 0.000 description 2
- HTUMBQDCCIXGCV-UHFFFAOYSA-N lead oxide Chemical compound [O-2].[Pb+2] HTUMBQDCCIXGCV-UHFFFAOYSA-N 0.000 description 2
- GIWKOZXJDKMGQC-UHFFFAOYSA-L lead(2+);naphthalene-2-carboxylate Chemical class [Pb+2].C1=CC=CC2=CC(C(=O)[O-])=CC=C21.C1=CC=CC2=CC(C(=O)[O-])=CC=C21 GIWKOZXJDKMGQC-UHFFFAOYSA-L 0.000 description 2
- YEXPOXQUZXUXJW-UHFFFAOYSA-N lead(II) oxide Inorganic materials [Pb]=O YEXPOXQUZXUXJW-UHFFFAOYSA-N 0.000 description 2
- 239000011707 mineral Substances 0.000 description 2
- 235000010755 mineral Nutrition 0.000 description 2
- 239000002480 mineral oil Substances 0.000 description 2
- 125000005609 naphthenate group Chemical group 0.000 description 2
- 238000006386 neutralization reaction Methods 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000000638 solvent extraction Methods 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- -1 alkali metal salts Chemical class 0.000 description 1
- 235000021028 berry Nutrition 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 229910017052 cobalt Inorganic materials 0.000 description 1
- 239000010941 cobalt Substances 0.000 description 1
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 description 1
- 235000009508 confectionery Nutrition 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 1
- 239000003350 kerosene Substances 0.000 description 1
- 239000011133 lead Substances 0.000 description 1
- 239000010688 mineral lubricating oil Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- 125000001741 organic sulfur group Chemical group 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 235000011121 sodium hydroxide Nutrition 0.000 description 1
- 150000003463 sulfur Chemical class 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
- 239000002699 waste material Substances 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
Definitions
- This invention relates to a method of refining crude naphthenic acid which contains various impurities including acidic organic sulfur compounds and neutral oils. More particularly, my invention relates to th-eimprovement in refining crude naphthenic acid containing normally liquid :organic acidic sulfur compounds, comprising the steps of heating said acids to elevated term peratures to decompose the sulfur compounds Q to neutral oils and gaseous sulfur compounds without effecting substantial decomposition of the naphthenic acids, removing the gases so formed, neutralizing the heat treated naphthenic acids with aqueous caustic alkali and extracting 5 the resulting soapsolution with a solvent for the unsaponifiable impurities.
- Naphthenic acids so obtained normally contain large proportions of impurities, chiefly sulfur compounds and neutral oils. These impurities greatly reduce the commercial value 3 and usefulness of the naphthenic acids by reason of lowering their neutralization number and by forming dark, unstable, heavy metal salts,
- the acidic sulfur compounds which areso diffi- 1D cult tor-emove from naphthenic acids containing them are believed to be sulfonlc acids or other organic sulfur acids. 1 have found that these acids may be converted to normally gaseous sulfur .compoundsand neutral oils by heating them in a suitable vessel, such as a shell still, at temperatures of about 500 (to 750 F. and preferably at temperatures from 600 to 700 F. without simultaneously decomposing the naphthenic acids lithe time of "heating is properly controlled. This 2 heating may be carried out at substantially atmospheric or superatmospheric pressures. Pressures from 5 tolOO lbs. gauge areespecially con- Venient.
- the proper time of heating may vary over a considerable range depending upon the exact temperature used. This is obvious from the known fact that the rate of thermal decomposition doubles approximately "with every temporature increment of 22 F. At 685 F. the proper timeis in therrange of Etc 30 minutes, and is more or less,-depending on the temperature, in approximatejaccord with the above law governing the rate of thermal reactions. 5
- the gas products formed during the heat treat- A ment areseparated from the naphthenic acid, eithercontinuously or intermittently and may be analyzed irnmediately for CO2. .As soon as the CO2 content "of the waste vapors arises above a certain predetermined maximum the heating is discontinued and the still charge is allowed to cool. The resulting. heat treated naphthenic acids are then neutralized with aqueous caustic After completed treatment as described above,
- the clear soap solution is acidified with an aqueous solution of a suitable mineral acid which is stronger than naphthenic acids, such as sulfuric, hydrochloric acid, etc. to liberate the naphthenic acids from the soaps.
- naphthenic acids such as sulfuric, hydrochloric acid, etc.
- Liberated naphthenic acids are separated from the resulting aqueous layer and'are washed with water to remove free mineral acid and salts.
- the washed naphthenic acids may now be used, if desired after distillation for preparing the desired light colored, heavy metal salts, such as lead, cobalt, copper, etc., naphthenates, which are useful for many purposes.
- the purified naphthenic acids may be fractionally distilled to produce several grades of the desired naphthenates.
- Example A crude naphthenic acid containing about of sulfur acids and other sulfur compounds was placed in a still and heated under lbs. gauge to a temperature of 685 F.
- the waste gases were vented through a watercooled condenser to condense escaping oil and naphthenic acids.
- the temperature of 685 F. was maintained for about ten minutes, and as after the lapse of this time the formation of hydrogen sulfide had ceased, the still and its contents were allowed to cool.
- the recovered liquid distillate was combined with the still bottoms and the mixture neutralized with the stoichiometric quantity of caustic soda.
- the resulting soap was dissolved in water, heated to about 200 F. to facilitate separation of neutral oils, and the separated neutral oils were removed.
- the solution was then washed four times with a low sulfur naturally sweet kerosene to remove dark colored neutral oils formed while decomposing the sulfur compounds.
- the purified soap solution wasacidified' with dilute sulfuric acid and the separated naphthenic acids recovered. These acids upon distillation yielded Very light colored naththenic acids that upon reacting with litharge formed light colored lead naphthenates. Distilling the original naphthenic acids, without first subjecting them to the purification process, yielded naphthenic acids that upon reacting with litharge formed almost black colored lead naphthenates.
- the improvement comprising heating the crude 3.
- naphthenic acid to a temperature of about 600 F. to 700 F. and under a pressure of about 5 to pounds until gaseous sulfur compounds are no longer evolved and separating said sulfur compounds from the heat treated acids and dis- ,5 solving said acids in aqueous caustic alkali to form said soap solution.
Description
Patented May I4, 1946 .ATENT orrics PROCESS FOR THE REF-INING 01 NAPHTHENIU ACIDS Hugh .RogersBen'y, Alton, .111. .assignor to Shell Development Company, San Francisco, cairn,
'a ocrporation of Delaware No Drawing. Application nuym, 19.39, Serial No. 286,238
5 Claims. (01. 260 -514) This invention relates to a method of refining crude naphthenic acid which contains various impurities including acidic organic sulfur compounds and neutral oils. More particularly, my invention relates to th-eimprovement in refining crude naphthenic acid containing normally liquid :organic acidic sulfur compounds, comprising the steps of heating said acids to elevated term peratures to decompose the sulfur compounds Q to neutral oils and gaseous sulfur compounds without effecting substantial decomposition of the naphthenic acids, removing the gases so formed, neutralizing the heat treated naphthenic acids with aqueous caustic alkali and extracting 5 the resulting soapsolution with a solvent for the unsaponifiable impurities.
.Naphthcnic acids are produced largely byexQ tracting unrefined :mineral oils containing the same with alkaline oil-insoluble liquids, and
3 acidifying the extract to liberate extracted naphthenic acids. Naphthenic acids so obtained normally contain large proportions of impurities, chiefly sulfur compounds and neutral oils. These impurities greatly reduce the commercial value 3 and usefulness of the naphthenic acids by reason of lowering their neutralization number and by forming dark, unstable, heavy metal salts,
. such as the lead salts, Presence of these in:-
purities makes the salts unsuitable for use .as
l paint drlers, extreme pressure compounds mineral lubricating oils, adhesives, and for many other purposes.
It is .known that extracting an aqueoussolution of the alkali metal salts of some crude 3 naphthenic acid with a hydrocarbon oillmay remove said impurities. However, I have .found that crude naphthenic acids produced ,fromcertain .mineral oils contain organic sulfur compounds having acidicjproperties so nearly resembling naphthenic acidsin thematterof their acid propertiesthat separation by neutralization with aqueous caustic .alkaliiand extraction with a solvent for the .unsaponifiable impurities is in-.
eficctive in removing said sulfur compounds. 5 Moreover, as these organic acidicsulfur com pounds are normally liquid andmay have boiling ranges comparable .to those of naphthenic acids, separation by distillation isnot feasible.
It iiS a purpose of this invention to provide a" methods of refining crude naphthenic acids by solvent extraction of their aqueous soap solution, so to make this method applicable to naphthenic acids containingyorganic acidic sulfur ccnipoundsnot heretofore separableby simple means. Acids produced in accordance with my 5 invention are capable of forming light-colored} heavy metal salts, and, in particular, lead salts whichdo not "tum black upon preparation or standing.
The acidic sulfur compounds which areso diffi- 1D cult tor-emove from naphthenic acids containing them are believed to be sulfonlc acids or other organic sulfur acids. 1 have found that these acids may be converted to normally gaseous sulfur .compoundsand neutral oils by heating them in a suitable vessel, such as a shell still, at temperatures of about 500 (to 750 F. and preferably at temperatures from 600 to 700 F. without simultaneously decomposing the naphthenic acids lithe time of "heating is properly controlled. This 2 heating may be carried out at substantially atmospheric or superatmospheric pressures. Pressures from 5 tolOO lbs. gauge areespecially con- Venient. "Therefore, I precede the known refining by solvent extraction of the soap solution with 5 a heat treatment for atime sufficient to break down these acidic sulfur compounds. On the other hand, "the time of heating must not be so long, to cause substantial evolution of C02. This canreadily be achieved as naphthenic acids, ingenera'htere sufficiently'stable within the above temperature range to enable substantially complete decomposition of acidicorganic sulfur compounds without decomposition of the naphthenic acids.
The proper time of heating may vary over a considerable range depending upon the exact temperature used. This is obvious from the known fact that the rate of thermal decomposition doubles approximately "with every temporature increment of 22 F. At 685 F. the proper timeis in therrange of Etc 30 minutes, and is more or less,-depending on the temperature, in approximatejaccord with the above law governing the rate of thermal reactions. 5
The gas products formed during the heat treat- A ment areseparated from the naphthenic acid, eithercontinuously or intermittently and may be analyzed irnmediately for CO2. .As soon as the CO2 content "of the waste vapors arises above a certain predetermined maximum the heating is discontinued and the still charge is allowed to cool. The resulting. heat treated naphthenic acids are then neutralized with aqueous caustic After completed treatment as described above,
the clear soap solution is acidified with an aqueous solution of a suitable mineral acid which is stronger than naphthenic acids, such as sulfuric, hydrochloric acid, etc. to liberate the naphthenic acids from the soaps. Liberated naphthenic acids are separated from the resulting aqueous layer and'are washed with water to remove free mineral acid and salts. The washed naphthenic acids may now be used, if desired after distillation for preparing the desired light colored, heavy metal salts, such as lead, cobalt, copper, etc., naphthenates, which are useful for many purposes. Further, if desired, the purified naphthenic acids may be fractionally distilled to produce several grades of the desired naphthenates.
The following example further illustrates our process.
Example A crude naphthenic acid containing about of sulfur acids and other sulfur compounds was placed in a still and heated under lbs. gauge to a temperature of 685 F. The waste gases were vented through a watercooled condenser to condense escaping oil and naphthenic acids. The temperature of 685 F. was maintained for about ten minutes, and as after the lapse of this time the formation of hydrogen sulfide had ceased, the still and its contents were allowed to cool. The recovered liquid distillate was combined with the still bottoms and the mixture neutralized with the stoichiometric quantity of caustic soda. The resulting soap was dissolved in water, heated to about 200 F. to facilitate separation of neutral oils, and the separated neutral oils were removed. The solution was then washed four times with a low sulfur naturally sweet kerosene to remove dark colored neutral oils formed while decomposing the sulfur compounds.
The purified soap solution wasacidified' with dilute sulfuric acid and the separated naphthenic acids recovered. These acids upon distillation yielded Very light colored naththenic acids that upon reacting with litharge formed light colored lead naphthenates. Distilling the original naphthenic acids, without first subjecting them to the purification process, yielded naphthenic acids that upon reacting with litharge formed almost black colored lead naphthenates.
I claim as my invention:
1. In the process of refining crude naphthenic acid containing normally liquid acidic organic sulfur compounds by extracting an aqueous soap solution of said naphthenic acids with a water ganic sulfur compounds thereby converting said 5 organic sulfur compounds to neutral oils and normally gaseous sulfur compounds and to produce heat treated naphthenic acids, separating the said gaseous compounds from the heat treated acids and dissolving said acids in aqueous caustic 1C alkali to form said soap solution.
2. In the process of refining crude naphthenic acid containing normally liquid acidic organic sulfur compounds by extracting an aqueous soap solution of said naphthenic acids with a Water im- 1! miscible solvent for unsaponifiable impurities with which crude naphthenic acids are usually associated, the improvement comprising heating the crude naphthenic acid to a temperature of about 500 F. to 750 F. and under superatmos- 2| pheric pressure for a time sumcient to decompose the organic acidic sulfur compounds to form normally gaseous sulfur compounds and neutral oils and insufiicient to liberate substantial amounts of CO2 and separating the said gaseous 21 compounds from the heat treated acids and dissolving said acids'in aqueous caustic alkali to form said soap solution.
3. In the process of preparing purified naphthenic acid by extracting an aqueous alkaline so- 3 lution of crude naphthenic acids containing normally liquid acidic organic sulfur compounds by extracting an aqueous soap solution of said naphthenic acids with a volatile petroleum distillate,
the improvement comprising heating the crude 3.
naphthenic acid to a temperature of about 600 F. to 700 F. and under a pressure of about 5 to pounds until gaseous sulfur compounds are no longer evolved and separating said sulfur compounds from the heat treated acids and dis- ,5 solving said acids in aqueous caustic alkali to form said soap solution.
4. In the process of preparing purified naphthenic acid by extracting an aqueous alkaline solution of crude naphthenic acids containing 4 normally liquid acidic organic sulfur compounds by extracting an aqueous soap solution of said naphthenic acids with a volatile petroleum distillate, the improvement comprising heating the crude naphthenic acid to a temperature of about 5 600 F. to 700 F. for 5 to 30 minutes and under a pressure of 5 to 100 pounds and separating the gaseous sulfur compounds formed from the heat treated acids and dissolving said acids in aqueous caustic alkali to form said soap" solution. 5
5. In the process of preparingpurified naphthenic acid by extracting an aqueous alkaline solution of crude naphthenic acids containing normally liquid acidic organic sulfur compounds by extracting an aqueous soapsolution of said 6 naphthenic acids with avolatile petroleum distillate, the improvement comprising heating the crude naphthenic acid to a temperature of about 685 F. for about 10 minutes and under a pressure of 35 pounds and separating the gaseous 6 sulfur compounds formed from the heat treated acids and dissolving said acids in aqueous caustic alkali to form said soap solution.
I-IUGl-I ROGERS BERRY,
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US286238A US2200711A (en) | 1939-07-24 | 1939-07-24 | Process for the refining of naphthenic acids |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US286238A US2200711A (en) | 1939-07-24 | 1939-07-24 | Process for the refining of naphthenic acids |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2200711A true US2200711A (en) | 1940-05-14 |
Family
ID=23097693
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US286238A Expired - Lifetime US2200711A (en) | 1939-07-24 | 1939-07-24 | Process for the refining of naphthenic acids |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2200711A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2802867A (en) * | 1957-08-13 | Method of refining naphthenic acids | ||
| US2815372A (en) * | 1955-01-12 | 1957-12-03 | Armstrong Cork Co | Method of making alkaline earth metal naphthenates |
-
1939
- 1939-07-24 US US286238A patent/US2200711A/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2802867A (en) * | 1957-08-13 | Method of refining naphthenic acids | ||
| US2815372A (en) * | 1955-01-12 | 1957-12-03 | Armstrong Cork Co | Method of making alkaline earth metal naphthenates |
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