US3692861A - Process for producing highly pure isoprene - Google Patents

Process for producing highly pure isoprene Download PDF

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Publication number
US3692861A
US3692861A US111871A US3692861DA US3692861A US 3692861 A US3692861 A US 3692861A US 111871 A US111871 A US 111871A US 3692861D A US3692861D A US 3692861DA US 3692861 A US3692861 A US 3692861A
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United States
Prior art keywords
sodium
equivalent
process according
acetylenes
sulfur compounds
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Expired - Lifetime
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US111871A
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English (en)
Inventor
Tatsusuke Chikatsu
Shinichi Shimokawa
Yoshinori Yoshida
Masatugu Imamura
Ituo Nishiwaki
Toshio Akimoto
Tatuji Fujiwara
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JSR Corp
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Japan Synthetic Rubber Co Ltd
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Priority claimed from JP1002670A external-priority patent/JPS493493B1/ja
Priority claimed from JP11573170A external-priority patent/JPS4911682B1/ja
Application filed by Japan Synthetic Rubber Co Ltd filed Critical Japan Synthetic Rubber Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C7/00—Purification; Separation; Use of additives
    • C07C7/148—Purification; Separation; Use of additives by treatment giving rise to a chemical modification of at least one compound
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C7/00—Purification; Separation; Use of additives
    • C07C7/005—Processes comprising at least two steps in series
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C7/00—Purification; Separation; Use of additives
    • C07C7/148—Purification; Separation; Use of additives by treatment giving rise to a chemical modification of at least one compound
    • C07C7/14833—Purification; Separation; Use of additives by treatment giving rise to a chemical modification of at least one compound with metals or their inorganic compounds
    • C07C7/14841—Purification; Separation; Use of additives by treatment giving rise to a chemical modification of at least one compound with metals or their inorganic compounds metals

Definitions

  • CYCLICAL PROCESS FOR THE DEHYDROGENATION OF SATURATED HYDROCARBONS The production of olefins and diolefins from paraffins of the same carbon structure is based essentially on simple catalytic dehydrogenation processes. This type of conversion involves a balanced reaction conforming to the laws of thermodynamics; in order to achieve industrially acceptable performances it is necessary to use rather unfavorable operating conditions: high temperature, lower hydrocarbon pressure.
  • the most economical way therefor consists of introducing air or oxygen for converting the hydrogen to water by combustion.
  • a number of processes has been proposed in the case of preparing diolefins by controlled oxidation of olefins in the presence of catalysts, but the rare examples of production of olefins and diolefins by oxidizing paraffms are generally characterized by poor performances, mainly as the result of the degradation reactions involving a complete combustion due to the simultaneous presence, in the gaseous reaction medium of hydrocarbons and oxygen.
  • This process offers, with respect to the known processes for oxidation of paraffins, numerous advantages, mainly a high selectivity and a high yield even at a moderate reaction temperature and relatively high pressure, Moreover, due to the operation in the absence of oxygen it is possible to avoid secondary reactions of degradation which otherwise occur when hydrocarbons and oxygen are present in the reaction medium, said reactions resulting in the formation of the carbon dioxide in non-negligible amounts thereby leading on the one hand to the loss of a portion of the paraffins and on the other hand to temperature increases which are detrimental to the oxidation reaction.
  • paraffins which may be used according to the present invention are linear or branched paraffins containing from two to 10 and preferably from four to eight carbon atoms.
  • the process may be carried out by means of any apparatus whereby is achieved an alternate contact of the molybdate with the gaseous phase containing the paraffms, either alone or diluted with an inert gas such as nitrogen, carbon dioxide or steam, and thereafter of the reduced molybdate with the oxygen-containing gaseous phase, the process being by no way limited to the use of any particular apparatus.
  • an inert gas such as nitrogen, carbon dioxide or steam
  • the reaction can be carried out in a reaction vessel operated under dynamic conditions; reactants, injected under a pressure between 0.1 and 2 atmospheres, are successively introduced into the reac tion vessel containing the slid mass in the form of grains, extrudates or powder, having a size elected, in accordance with the type of operation: in a fixed bed for example there can be used particles of a diameter for instance between 0.1 and 50 mm; in a fluid bed, smaller diameters will be preferred in order to obtain a good stability of the bed, for instance diameters between 0.01 and 0.2 mm; in a moving bed, i.e. when the solid catalyst is circulated in the reaction vessel, intermediate sizes of, f.i.,'0.05 to 0.5 mm can be used.
  • the successive introduction of the reactants, paraffin and oxygen or air may be regulated by a system of automatically operated valves wherein each valve can be open only after the closure of the other valves.
  • an intermediate supplemental injection of an inert gas nitrogen, steam, carbon dioxide, for example.
  • the operating cycle will thus include the successive steps of l. Injecting paraffms on the molybdate, resulting in the production of olefins and diolefins and in at least a partial reduction of the molybdate to molybdite.
  • This invention relates to an improvement in process for purifying isoprene, and more particularly to an improvement in process for preparing polymerization grade isoprene from the C, hydrocarbon faction derived from the cracking of petroleum, especially naphtha.
  • the C, hydrocarbon fractionof naphtha-cracked oil usually contains several ten kinds of C C, hydrocarbon components, and the boiling points and relative volatilities to isoprene of the main components are shown in Table 1.
  • polymerization-retarding materials such as cyclopentadiene, acetylenes and allenes contained in the C, hydrocarbon fraction are preliminarily removed by prior well-known process and, thereafter, remaining polymerization-retarding materials such as sulfur compounds, a-acetylenes, and cyclopentadiene are removed by treating with a mixture of metallic sodium and a minor amount of aliphatic alcohol without almost any loss of isoprene;
  • the process for purifying olefines through contact with sodium'to remove a very small amount of impurities contained in the olefines is well known, and has been generally used on a laboratory scale.
  • impurities such as water and sulfur compounds
  • sodium is poisoned in case of said well-known sodium treatment process alone, so the a-acetylenes, allenes and cyclopentadiene remain as'they are. Therefore, in the case of sodium treatment, is necessary-to provide a step for removing water and sulfurin advance.
  • the sulfur compounds contained in the C, hydrocarbon fraction there are mentioned hydrogen sulfide, mercaptanes, sulfides and carbon disulfide. Carbon disulfide cannot be removed by alkali washing, and thus it is necessary to remove it by some other means.
  • An object of the present invention is to provide a process for removing polymerization-retarding substances more effectively.
  • the present invention is to provide a process for separating and purifying isoprene from a C, hydrocarbon fraction containing C, paraffins, C, monoolefines, C, diolefines, C, acetylenes, a small amount of C and C, hydrocarbon fractions, and sulfur compounds which comprises a. removing a major portion of cyclopentadiene and acetylenes contained in the fraction by previously known procedures, and
  • cyclopentadiene is removed by above-mentioned dimerization process and major portion of acetylenes are removed by straight distillation in the presence of isopentane contained in the C, hydrocarbon fraction before the present sodium-alcohol treatment.
  • Extractive distillation process may be applied after the sodium-alcohol treatment, but preferably applied before the treatment from the viewpoint of efficiency of the treatment.
  • extractive solvent used in the extractive distillation process such conventional solvents, as acetonitrile, dimethylformamide, acetone, furfural and N-methyl pyrrolidone, etc., may be used.
  • the C hydrocarbon fraction is led to a dimerization reactor and heated to 90 130C for l 30 hours, preferably 1 hours, and the resulting dimer of cyclopentadiene is removed together with other high boiling point materials in successive distillation column.
  • cyclopentadiene is removed to about 3 percent or less by weight.
  • the acetylenes contained in the C hydrocarbon fraction form an azeotropic mixture with isopentane also contained in the fraction and are removed to about 10 200 ppm by distillation, though it depends on conditions of the distillation.
  • Allenes especially 1,2-butadiene are removed in this process to such a degree that they have substantially no effect on polymerization.
  • a process for obtaining highly pure isoprene by removing substantially all of cyclopentadiene-and acetylenes according to the procedures of (1) heat soaking (dimerization of cyclopentadiene), (2) removal of high boiling point materials, (3) removal of low boiling point materials and (4) extractive distillation is disclosed, 'for example, in British Patent Specification No. 1,137,268.
  • the removal of sulfur compounds is a problem in the process.
  • the extract derived from the extractive distillation column is introduced to the second extractive distillation column to remove diolefines and acetylene having larger solubilities than that of isoprene. Then, to remove the polymerization-retarding impurities to ppm order, it is necessary to provide another distillation columns, topping and tailing columns for removing low boiling point and high boiling point components respectively.
  • acetylenes are azeotropically distilled off with isopentane contained in the C hydrocarbon fraction in the topping column, and then the remaining acetylenes, cyclopentadiene and sulfur compounds are readily removed by the sodium treatment in the presence of aliphatic alcohol in amount of not more than that of sodium by equivalent.
  • the present inventors have found that the amount of sodi-- um can be considerably reduced when aliphatic alcohol having one to 18 carbon atoms is used together with sodium in amount of not more than that of sodium by equivalent, and further the polymerization of isoprene can be effectively prevented thereby. Furthermore, the present inventors have found that the sodium-alcohol treatment can be sufficiently applied, even if a considerably large amount of polymerization-retarding impurities are present.
  • the acetylenes remaining as the column bottom distillate in the topping column and cyclopentadiene and sulfur compounds remaining in the tailing column are removed by the sodium-alcohol treatment.
  • Sodium is usually dispersed in a medium as particles having sizes of l to microns and used "in such a dispersed state.
  • the sodium dispersion can be prepared according to the conventional, well-known procedure.
  • media that are inactive to sodium and have a boiling point higher than the melting point of sodium for example, toluene, xylene, a mineral oil, petrolatum, naphthalene, tetraline, heptane, etc. are usually used.
  • the dispersion containing 20 60 percent by weight, preferably 40 50 percent by weight of sodium, is used in the sodium-alcohol treatment.
  • the alcohols used in the sodium-alcohol treatment are aliphatic monohydric alcohols having one to 18 carbon atoms, for example, as methyl, ethyl, propyl, butyl, amyl, hexyl, octyl, nomyl, decyl, lauryl, palmityl and stearyl alcohols.
  • lsopropyl, tert-butyl, isoamyl, octyl and lauryl alcohols are preferably used.
  • 0.5 to 1.5 parts, preferably 1.05 to 1.2 parts by equivalent of sodium is used for one part by equivalent of polymerization-retarding impurities, that is, cyclopentadiene, acetylenes and sulfur compounds.
  • the amount of said alcohols used is not more than that of sodium by equivalent and l 10 times, preferably 2 5 times that of the sulfur compounds by equivalent.
  • the alcohol can be used directly or after diluted with a solvent inactive to sodium.
  • Any temperature can be applied to the sodium-alcohol treatment so long as the isoprene is not polymerized and consequently consumed at that temperature, but usually a temperature below 40C is economical and preferable for carrying out the treatment.
  • reaction pressure of the reaction system of the sodium-alcohol treatment is usually atmospheric, because the handling is advantageous under the atmospheric pressure.
  • the treatment can be carried out under pressure.
  • the feed stream 1 was charged into a dimerizer A and most of cyclopentadiene in the feed stream was dimerized to dicyclopentadiene at a soaking temperature of 110 120C for a retention time of 6 hours,
  • the process stream 2 leaving the dimerizer A was led to the first distillation column 13 having 120 plates for removing the high boiling point components, and was operated with a reflux ratio of 5.0 at an overhead temperature of 63C and a bottom temperature of 95C under a pressure of 2.7 Kglcm
  • hydrocarbon stream 4 containing 16.6 percent by weight of isoprene and 0.21 percent by weight of cyclopentadiene was obtained. Recovering rate of isoprene was 95 percent.
  • the distillate stream 4 of the column B was led to the first topping column C having 120 plates for removing the low boiling point components, and was operated with a reflux ratio of 5.0 at an overhead temperature of 62C and bottom temperature of 95.5C under a pressure of 2.7 Kg/cm absolute, whereby the bottoms stream 5 containing 24.2 percent by weight of isoprene was obtained.
  • the bottoms fraction 5 of the column C was then led to the extractive distillation column D having 100 plates, and was operated with a reflux ratio of 3.0 at an by weight of water was selected and fed to the column at 10th plate from the top of column in a proportion of the solvent to the fed C hydrocarbon fraction of 6 l by weight.
  • the bottoms stream? of the column D containing diolefines such as isoprene and acetylene was fed to the stripping column E together with the solvent, where the process stream was separated from the solvent, acetonitrile.
  • the overhead fraction 10 was then fed to the water washing column F, where the acetonitrile still contained in the isoprene stream was eliminated to less than 5 ppm, and then the isoprene stream 11 was fed to the second topping column G having 120 plates for removing the low boiling point components, and was operated with a reflux ratio of 280 at an overhead temperature of 56C and bottom temperature of C under a pressure of 2.0 Kg/cm absolute.
  • the components having lower boiling points than that of isoprene, such as 1,4-pentadiene, 2-butyne, etc. were eliminated from the isoprene stream to such a degree that they will no more retard the polymerization, and at the same time water was eliminated therefrom to a trace into the stream 12.
  • the treating agent a sodium dispersion having sizes of 10 to microns and concentration of about 40 percent by weight in xylene was used.
  • isopropyl alcohol was used as the alcohol component.
  • the amounts of the treating agents were as follows,
  • Na/polymerization-retarding impurities (cyclopentadiene, acetylenes and sulfur compounds) l.10/l (by equivalent) isopropyl alcohol/sulfur compounds I equivalent)
  • the polymerization-retarding impurities that is acetylenes, cyclopentadienes and sulfur compounds, were eliminated therefrom to a trace through reaction at a reaction temperature of 30C for a reaction time of 3 hours. In this procedure, the loss of isoprene was negligibly small.
  • a process for separating purified isoprene from a C hydrocarbon fraction derived from cracking of petroleum containing C paraffmes, C monoolefines, C diolefines, C acetylenes, a small amount of C, and C hydrocarbons and sulfur compounds which comprises:
  • a removing a major portion of cyclopentadiene and acetylenes contained in said fraction as polymerization retarding impurities according to dimerization by heat soaking and distillation, and distillation, respectively and b. treating the fraction with sodium containing aliphatic monohydric alcohol having one to 18 carbon atoms in amount of not more than that of sodium by equivalent to remove the .remaining cyclopentadiene, acetylenes and sulfur compounds.
  • the i'z g x 'gx 5;: 40 amount of the alcohol is l 10 parts by equivalent for l 3: h i-l-b tyne 0:1 1 part by equivalent of the remaining sulfur compounds.
  • a r 23 9.
  • i sb pz ri e 1 10.
  • aln-pentane 251.8 5 cohol is selected from the group consisting of methyl, Z-pentene mmelhybzbmem (transcis) 218 ethyl, propyl, butyl, amyl, hexyl, octyl, nonyl, decyl, l-pentyne 0.02 lauryl, palmityl and stearyl alcohols.
  • fy g gg g-g 11.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Analytical Chemistry (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Water Supply & Treatment (AREA)
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  • Inorganic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
US111871A 1970-02-06 1971-02-02 Process for producing highly pure isoprene Expired - Lifetime US3692861A (en)

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JP1002670A JPS493493B1 (https=) 1970-02-06 1970-02-06
JP11573170A JPS4911682B1 (https=) 1970-12-23 1970-12-23

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DE (1) DE2105523C3 (https=)
ES (1) ES387987A1 (https=)
FR (1) FR2078217A5 (https=)
GB (1) GB1325932A (https=)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3947506A (en) * 1974-04-03 1976-03-30 The Goodyear Tire & Rubber Company Recovery of isoprene
US4392004A (en) * 1982-02-22 1983-07-05 The Goodyear Tire & Rubber Company Reduction of cyclopentadiene from isoprene streams
US4438289A (en) 1982-02-22 1984-03-20 The Goodyear Tire & Rubber Company Reduction of cyclopentadiene from isoprene streams
US5397492A (en) * 1993-06-07 1995-03-14 Ossian, Inc. Non-oil based sweeping compound
US20020164278A1 (en) * 1998-12-17 2002-11-07 Vetter Michael J. Apparatus with increased yield and selectivity using side-by-side reaction zones
RU2266887C1 (ru) * 2004-06-29 2005-12-27 Открытое акционерное общество "Нижнекамскнефтехим" Способ очистки c5-углеводородов
WO2014203207A1 (en) 2013-06-19 2014-12-24 Saudi Basic Industries Corporation Co-extraction systems for separation and purification of butadiene and isoprene
US9885061B2 (en) * 2009-03-03 2018-02-06 Amyris, Inc. Microbial derived isoprene and methods for making the same
US9981889B2 (en) 2013-08-22 2018-05-29 General Electric Company Use of diethylenetriamine as a CS2 scavenger in isoprene production

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL168202C (nl) * 1971-10-29 1982-03-16 Shell Int Research Werkwijze voor het zuiveren van isopreen.
US4482771A (en) * 1983-01-03 1984-11-13 The Dow Chemical Company Anionic polymerization of cis- and trans-1,3-pentadiene from a mixture of saturated and unsaturated hydrocarbons
RU2285688C1 (ru) * 2005-06-06 2006-10-20 Открытое акционерное общество "Нижнекамскнефтехим" Способ получения изопрена

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2398973A (en) * 1942-10-03 1946-04-23 United Gas Improvement Co Purification of isoprene
US3091653A (en) * 1958-12-24 1963-05-28 Bayer Ag Processes for purifying conjugated diolefins
US3285989A (en) * 1964-12-28 1966-11-15 Goodrich Gulf Chem Inc Isoprene sodium treatment process
US3301915A (en) * 1964-11-06 1967-01-31 Internat Synthetic Rubber Comp Recovery of isoprene from hydrocarbon fractions

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2398973A (en) * 1942-10-03 1946-04-23 United Gas Improvement Co Purification of isoprene
US3091653A (en) * 1958-12-24 1963-05-28 Bayer Ag Processes for purifying conjugated diolefins
US3301915A (en) * 1964-11-06 1967-01-31 Internat Synthetic Rubber Comp Recovery of isoprene from hydrocarbon fractions
US3285989A (en) * 1964-12-28 1966-11-15 Goodrich Gulf Chem Inc Isoprene sodium treatment process

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3947506A (en) * 1974-04-03 1976-03-30 The Goodyear Tire & Rubber Company Recovery of isoprene
US4392004A (en) * 1982-02-22 1983-07-05 The Goodyear Tire & Rubber Company Reduction of cyclopentadiene from isoprene streams
US4438289A (en) 1982-02-22 1984-03-20 The Goodyear Tire & Rubber Company Reduction of cyclopentadiene from isoprene streams
US5397492A (en) * 1993-06-07 1995-03-14 Ossian, Inc. Non-oil based sweeping compound
US20020164278A1 (en) * 1998-12-17 2002-11-07 Vetter Michael J. Apparatus with increased yield and selectivity using side-by-side reaction zones
US6969496B2 (en) * 1998-12-17 2005-11-29 Uop Llc Apparatus with increased yield and selectivity using side-by-side reaction zones
RU2266887C1 (ru) * 2004-06-29 2005-12-27 Открытое акционерное общество "Нижнекамскнефтехим" Способ очистки c5-углеводородов
US9885061B2 (en) * 2009-03-03 2018-02-06 Amyris, Inc. Microbial derived isoprene and methods for making the same
US10125376B2 (en) 2009-03-03 2018-11-13 Amyris, Inc. Microbial derived isoprene and methods for making the same
WO2014203207A1 (en) 2013-06-19 2014-12-24 Saudi Basic Industries Corporation Co-extraction systems for separation and purification of butadiene and isoprene
CN105324353A (zh) * 2013-06-19 2016-02-10 沙特基础工业公司 用于分离和纯化丁二烯和异戊二烯的共提取系统
US9656929B2 (en) 2013-06-19 2017-05-23 Saudi Basic Industries Corporation Co-extraction systems for separation and purification of butadiene and isoprene
CN105324353B (zh) * 2013-06-19 2017-10-17 沙特基础工业公司 用于分离和纯化丁二烯和异戊二烯的共提取系统
US9981889B2 (en) 2013-08-22 2018-05-29 General Electric Company Use of diethylenetriamine as a CS2 scavenger in isoprene production

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DE2105523C3 (de) 1974-08-15
GB1325932A (en) 1973-08-08
FR2078217A5 (https=) 1971-11-05
DE2105523A1 (de) 1971-12-09
DE2105523B2 (de) 1974-01-17
ES387987A1 (es) 1974-02-16

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