US3067269A - Process for the recovery of naphthalene - Google Patents
Process for the recovery of naphthalene Download PDFInfo
- Publication number
- US3067269A US3067269A US381780A US38178053A US3067269A US 3067269 A US3067269 A US 3067269A US 381780 A US381780 A US 381780A US 38178053 A US38178053 A US 38178053A US 3067269 A US3067269 A US 3067269A
- Authority
- US
- United States
- Prior art keywords
- naphthalene
- oil
- cooling
- press
- mixture
- 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
- UFWIBTONFRDIAS-UHFFFAOYSA-N Naphthalene Chemical compound C1=CC=CC2=CC=CC=C21 UFWIBTONFRDIAS-UHFFFAOYSA-N 0.000 title claims description 184
- 238000000034 method Methods 0.000 title claims description 13
- 230000008569 process Effects 0.000 title claims description 10
- 238000011084 recovery Methods 0.000 title description 3
- 239000003921 oil Substances 0.000 claims description 27
- 239000013078 crystal Substances 0.000 claims description 18
- 239000000203 mixture Substances 0.000 claims description 17
- 238000002844 melting Methods 0.000 claims description 9
- 230000008018 melting Effects 0.000 claims description 9
- 239000010413 mother solution Substances 0.000 claims description 6
- 230000009471 action Effects 0.000 claims description 4
- 239000010779 crude oil Substances 0.000 claims description 4
- 238000004898 kneading Methods 0.000 claims description 4
- 239000012452 mother liquor Substances 0.000 claims description 4
- 239000012530 fluid Substances 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 claims description 3
- 238000001816 cooling Methods 0.000 description 27
- 239000000463 material Substances 0.000 description 24
- 238000007711 solidification Methods 0.000 description 22
- 230000008023 solidification Effects 0.000 description 22
- 238000003825 pressing Methods 0.000 description 18
- 238000004821 distillation Methods 0.000 description 10
- 239000002904 solvent Substances 0.000 description 9
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 6
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- 150000002989 phenols Chemical class 0.000 description 6
- 238000010438 heat treatment Methods 0.000 description 5
- 239000007788 liquid Substances 0.000 description 5
- 230000001105 regulatory effect Effects 0.000 description 5
- 239000007787 solid Substances 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 239000012535 impurity Substances 0.000 description 4
- 238000009434 installation Methods 0.000 description 4
- 239000010802 sludge Substances 0.000 description 4
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 238000002425 crystallisation Methods 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 239000007858 starting material Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 238000009835 boiling Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000011280 coal tar Substances 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 230000000750 progressive effect Effects 0.000 description 2
- 239000011269 tar Substances 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 1
- 229920004482 WACKER® Polymers 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 239000000498 cooling water Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 150000002576 ketones Chemical class 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 150000002790 naphthalenes Chemical class 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 235000011149 sulphuric acid Nutrition 0.000 description 1
- 239000001117 sulphuric acid Substances 0.000 description 1
- -1 that is to say Chemical compound 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D9/00—Crystallisation
- B01D9/0004—Crystallisation cooling by heat exchange
- B01D9/0013—Crystallisation cooling by heat exchange by indirect heat exchange
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D9/00—Crystallisation
- B01D9/0059—General arrangements of crystallisation plant, e.g. flow sheets
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/14—Purification; Separation; Use of additives by crystallisation; Purification or separation of the crystals
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S425/00—Plastic article or earthenware shaping or treating: apparatus
- Y10S425/812—Venting
Definitions
- the warm crude naphthalene is first freed from phenols and then cooled in vats.
- the mother liquor has been drained oif, the crystallised naphthalene is hacked out of the vat, comminuted and centrifuged, whereby a somewhat purer crude naphthalene is obtained.
- This product is converted under mild heating into a doughy state in which it is introduced in portions into a press having sieve-like walls and a corresponding base.
- a ram the material is compressed and the mother solution still adhering to the naphthalene crystals is thus separated off to a considerable extent, while the naphthalene is compressed into the form of a cake.
- naphthalene having a solidification point of over 79 C. can be obtained, depending upon the choice of the working temperature.
- the naphthalene cake removed from the press which normally has a weight of about 20 kg. and a diameter of about 500 mm. is externally still covered with oil which must be wiped off as far as possible. In order to make this naphthalene ready for dispatch, it must thereafter be suitably comminuted.
- warm pressed naphthalene is obtained in a substantially simpler manner, intermediate crystallisation in vats, re-heating and chemical washing of the napthalene with subsequently highly selective distillation being unnecessary.
- the crude naphthalene fraction emanating from the distillation of crude tar or oil is worked up directly to form a normal commercial warm pressed material, preferably without previous removal of phenols, by first separating impure solid naphthalene from the starting material by cooling to a suitable temperature below 60 C. and then subjecting the said naphthalene in a lumpy condition, after separation from the mother solution, to a preferably continuous pressing operation in which the material is pressed out in a thin layer with continuous movement.
- the pressing arrangement advantageously so operates that the naphthalene is compressed to some extent with a kneading action and with a progressive increase of the compressing pressure produced, while the crystals are shifted relatively to one another.
- This pressing arrangement must in additionoperate continuously in order to produce the advantage according to the invention, that is to say, the material continuously fed through the press is also continuously delivered after the pressing.
- the starting material the naphthalene fraction of which is cooled before entering the press to form lumpy naphthalene or a crystal sludge, loses its liquid oily constituents through the perforated casing of the worm press.
- the pressed material is delivered in a thin layer or in small lumps, the oily impurities being completely uniformly removed by suitable adjustment of the dimensions of the delivery aperture of the press.
- a certain temperature increase of the pressed material occurs in the worm press owing to the constant relative movement of the crystals with respect to one another.
- the value of the said temperature increase is dependent upon the temperature at which the material enters and upon the quantity of oil present in the material.
- the temperature may be regulated by means of a cooling or heating device which is housed, for example, in the worm shaft and/or in the casing of the press. It is thus possible with a high temperature of admission of the material into the machine to produce an appropriate additional cooling during the pressing operation. Alternatively, if the temperature of admission is low a temperature increase can be produced by means of steam or hot water.
- a cooling cylinder or the like affords, in addition to the possibility of continuously cooling the material as it is produced, the advantage that the quantity of product fed to the press may be regulated by adjusting the speed of the cylinder or the temperature of the cooling water or by regulating the depth of immersion of the cylinder in the oil bath.
- cooling drums, cooling worms, mechanical agitating mechanisms, endless cooling belts or the like may be employed. Oils having a low naphthalene content are preferably so prepared for the working-up in the press that the main quantity of the mother solution is removed after the crystallisation by if desired also being heatable.
- spe /gee known steps such as filtering, centrifuging, suction filtering and the like. It is particularly expedient in this case to employ a vibrating sieve by means of which the solid crystals may be separated from the liquid. The crystal sludge then formed may then be fed to the continuous press for further working-up, as hereinbefore described.
- worm press instead of the worm press, other pressing apparatus, such as trace presses, displacement centrifuges or worm centrifuges may be employed, which operate with a progressive compression of the material, such arrangements being so operated that the material is moved during the pressing operation and is subjected to the pressure increasein a thin layer.
- pressing apparatus such as trace presses, displacement centrifuges or worm centrifuges may be employed, which operate with a progressive compression of the material, such arrangements being so operated that the material is moved during the pressing operation and is subjected to the pressure increasein a thin layer.
- a naphthalene having a solidification point of 79 C. was obtained after a single passage through the 'worm press from a naphthalene-containing crude oil fraction having a solidification point of 57 C. from which the phenols have not been removed.
- the process according to the invention may if desired, be combined with further novel steps for the purpose of producing s'o-called pure naphthalene, that is to say, naphthalene of which the solidification point lies above 79 C. and preferably above 80 0, without any chemical treatment having to be applied to the previously purified naphthalene for this purpose.
- pure naphthalene (solidi- 'ficati'on point 80 C. or higher) is obtained without chemical reaction and if desired without the usual subsequent re-distillation, by treating the previously purified naphthalene having a solidification point of about 79 C. with a solvent such as benzene or homologues, cooling the solution until lumpy naphthalene crystallises, and working up the naphthalene thereafter in a thin layer by means of the continuous pressing operation hereinbefore described after the solvent has been separated off.
- solvents such as methanol or other monovalent or 'polyvalent alcohols, ketones, esters and the like, may
- the pressing be effected in such manner that it takes place in a thin layer with constant movement of the crystals in relation to one another, preferably by means of a worm press.
- the material to be pressed is substantially freed very uniformly from the solvent in the press, since the material is in constant motion during the continuous pressing operation and an increasing pressure acts on relatively thin layers of pressed material.
- a worm press other pressing apparatus having a similar operation, for example a trace press, a displacement centrifuge or a worm centrifuge, may be employed provided that the I pressure therein is exerted on relatively thin layers of material.
- the installation for carrying out the process consists substantially of a container in which the material to be pressed is mixed with the solvent, the container preferably comprising a mechanical agitating mechanism and
- the installation further comprises a regulated feed-arrangement which delivers regulated quantities of the material to be treated into the pressing apparatus, a worm press or the like, as well as (:5. the said pressing apparatus itself.
- the said installation and the process are distinguished by particular simplicity, while in addition occupying little space. It is thus possible under particularly good condition to effect a continuous conversion of crude naphthalene or pre-purified naphthalene into pure naphthalene.
- a naphthalene crystal mixture having a solidification point of 70 C. was brought to a solidification of 792 C. by treatment in a worm press, thereafter recrystallised from a mixture of benzene, methanol and water and again pressed in the worm press.
- the pure naphthalene thus obtained had a solidification point of 79.84 C. On subsequent distillation, the solidification point rose to C.
- FIGURE 1 of the drawing represents an apparatus for performing the process according to the invention shown as a sectional view.
- FIGURE 2 of the drawing shows in diagrammatic form a modification of the procedure of the invention.
- the apparatus consists of the screw-press 1 fitted with a conically shaped housing 3, the smaller part extending in direction of the discharge end 2.
- the screw 4 is mounted on a hollow shaft 5, passing through the housing 3 of the press at its wider end and being tightened by a stuffing box 6.
- On the shaft 5 there is fixed atoothed wheel which is driven by a prime mover for the screw-press (not shown).
- Two pipes 8 and 9 are connected from outside to the hollow shaft of the press serving for the admission or discharge of a liquid or gaseous cooling or heating medium.
- the aperture of the mouth 2 of the press can be calibrated by a mouth-piece 13.
- This mouth piece 13 is adjusted by means of a spindle 14 in such a way that in the press such pressures are established as required for reaching the desired solidification point of the naphthalene. Whilst the oil separated during the pressing operation is moving towards the wider end of the press and running off through the perforations it the solid naphthalene is conveyed through the mouth 2 to a chute 15 from which it falls onto the conveyer belt 16 transporting the naphthalene to the point for further handling.
- the raw-material to be pressed is fed through a feeding hopper 17. To this the raw naphthalene is fed over a chute 18.
- a cooling drum l9 feeds the raw material to the aforesaid chute 18.
- the cooling drum 19 consists of a cylindrically shaped metallic drum maintained by inner cooling with water at a temperature below the solidificatron point of the naphthalene, preferably below 60 centigrades. This cooling drum turns at a relatively low speed, e.g. a few revolutions per minute, partially emergmg into a trough 2i filled to a certain level with the liq uid naphthalene oil 21.
- This layer is then removed from the cooling drum 19 by a scraper 22 in such a Way that a comparatively coarse maenemas terial is obtained which is fed by way of chute 18 to the feeding hopper 17 and from there to the screw-press.
- crude naphthalene is fed through worm press 30 of the same construction as the worm press of FIGURE 1.
- the oil is expressed in the manner indicated in FIGURE 1.
- the naphthalene is then dissolved in a solvent in tank 32, recrystallized by cooling the tank and the crystallized naphthalene removed from the tank and pressed continuously in worm press 34 of the same construction as the worm press disclosed in FIGURE 1.
- the purified naphthalene emerging from worm press 34 is dissolved in the solvent in tank 36 and the naphthalene recrystallized by cooling the tank.
- the crystals of naphthalene are removed from the tank and passed through worm press 38 to remove solvent and the naphthalene emerging from the press is recoverd.
- separating the naphthalene crystals from the mother solution subjecting the naphthalene so separated and still containing oil which adheres to the naphthalene and in lumpy form to a continuous kneading action while simultaneously advancing it under progressively increasing pressure through a channel, the walls of which have apertures, and simultaneously expressing the oil from the naphthalene through said apertures in the walls of the channel, said pressure being sufficient to simultaneously express substantially all of the oil from the naphthalene so that, by the time the naphthalene has advanced completely through the channel, it has a melting point above about 79 C.
- a process for the production of naphthalene having a melting point above about 79 C. from a mixture consisting essentially of a naphthalene-containing crude oil fraction which, upon cooling to a temperature below 60 C., forms a fluid mixture of naphthalene crystals and mother liquor, said mixture having a melting point substantially below 79 0., comprising cooling the impure mixture to a temperature below about 60 C.
- separating the naphthalene crystals from the mother solution subjecting the naphthalene so separated and still containing oil which adheres to the naphthalene and in the form of a dry sludge to a continuous kneading action While simultaneously advancing under progressively increasing pressure through a channel, the walls of which have apertures, and simultaneously expressing the oil from the naphthalene through said apertures in the walls of the channel, said pressure being suflicient to simultaneously express substantially all of the oil from the naphthalene so that, by the time the naphthalene has advanced completely through the channel, it has a melting point above about 79 C.
Landscapes
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Engineering & Computer Science (AREA)
- Analytical Chemistry (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Water Supply & Treatment (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE778063X | 1952-09-25 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3067269A true US3067269A (en) | 1962-12-04 |
Family
ID=6686891
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US381780A Expired - Lifetime US3067269A (en) | 1952-09-25 | 1953-09-23 | Process for the recovery of naphthalene |
US443685A Expired - Lifetime US2830104A (en) | 1952-09-25 | 1954-07-15 | Process for the recovery of naphthalene |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US443685A Expired - Lifetime US2830104A (en) | 1952-09-25 | 1954-07-15 | Process for the recovery of naphthalene |
Country Status (5)
Country | Link |
---|---|
US (2) | US3067269A (en, 2012) |
BE (1) | BE523046A (en, 2012) |
FR (1) | FR1093459A (en, 2012) |
GB (1) | GB778063A (en, 2012) |
NL (1) | NL104952C (en, 2012) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3523799A (en) * | 1966-11-25 | 1970-08-11 | Haas Inc John I | Process and apparatus for extraction of hops with a solvent |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL123392C (en, 2012) * | 1959-12-01 | 1900-01-01 | ||
US3304062A (en) * | 1964-09-23 | 1967-02-14 | Black Clawson Co | Apparatus for mixing and compacting material |
US3763769A (en) * | 1971-06-28 | 1973-10-09 | New Zealand Dairy Res Inst | Methods of pressing cheese |
FI70376C (fi) * | 1984-07-04 | 1986-09-19 | Neste Oy | Foerfarande och anordning foer separering eller rening av organiska aemnen |
FR2994659B1 (fr) * | 2012-08-22 | 2015-01-30 | Sarp Ind | Procede d'extraction et de purification de bromure de sodium |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US675179A (en) * | 1901-02-04 | 1901-05-28 | Charles Wacker | Rendering apparatus. |
GB255429A (en) * | 1925-07-15 | 1927-06-23 | Adam Meiro | Improved method of, and apparatus for the extraction of crystals from anthracene, naphthalene and the like distillates of coal tar |
GB380990A (en) * | 1931-11-14 | 1932-09-29 | Teerverwertung Gmbh | Process for obtaining solid pure naphthalene and similar solid pure substances from the molten substances |
US2078963A (en) * | 1934-03-03 | 1937-05-04 | Barrett Co | Process for refining crude naphthalene |
GB493992A (en) * | 1938-01-03 | 1938-10-18 | Evence Coppee & Cie | Improvements relating to the recovery of naphthalene |
US2321117A (en) * | 1942-05-15 | 1943-06-08 | Sherwin Williams Co | Purification of naphthalene |
US2701518A (en) * | 1950-10-23 | 1955-02-08 | Manuel C Mcdonald | Worm |
-
0
- NL NL104952D patent/NL104952C/xx active
- BE BE523046D patent/BE523046A/xx unknown
-
1953
- 1953-09-23 US US381780A patent/US3067269A/en not_active Expired - Lifetime
- 1953-09-25 FR FR1093459D patent/FR1093459A/fr not_active Expired
- 1953-09-25 GB GB26489/53A patent/GB778063A/en not_active Expired
-
1954
- 1954-07-15 US US443685A patent/US2830104A/en not_active Expired - Lifetime
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US675179A (en) * | 1901-02-04 | 1901-05-28 | Charles Wacker | Rendering apparatus. |
GB255429A (en) * | 1925-07-15 | 1927-06-23 | Adam Meiro | Improved method of, and apparatus for the extraction of crystals from anthracene, naphthalene and the like distillates of coal tar |
GB380990A (en) * | 1931-11-14 | 1932-09-29 | Teerverwertung Gmbh | Process for obtaining solid pure naphthalene and similar solid pure substances from the molten substances |
US2078963A (en) * | 1934-03-03 | 1937-05-04 | Barrett Co | Process for refining crude naphthalene |
GB493992A (en) * | 1938-01-03 | 1938-10-18 | Evence Coppee & Cie | Improvements relating to the recovery of naphthalene |
US2321117A (en) * | 1942-05-15 | 1943-06-08 | Sherwin Williams Co | Purification of naphthalene |
US2701518A (en) * | 1950-10-23 | 1955-02-08 | Manuel C Mcdonald | Worm |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3523799A (en) * | 1966-11-25 | 1970-08-11 | Haas Inc John I | Process and apparatus for extraction of hops with a solvent |
Also Published As
Publication number | Publication date |
---|---|
BE523046A (en, 2012) | |
NL104952C (en, 2012) | |
US2830104A (en) | 1958-04-08 |
GB778063A (en) | 1957-07-03 |
FR1093459A (fr) | 1955-05-05 |
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