GB585076A - Process for the production of meta-xylene - Google Patents

Process for the production of meta-xylene

Info

Publication number
GB585076A
GB585076A GB140145A GB140145A GB585076A GB 585076 A GB585076 A GB 585076A GB 140145 A GB140145 A GB 140145A GB 140145 A GB140145 A GB 140145A GB 585076 A GB585076 A GB 585076A
Authority
GB
United Kingdom
Prior art keywords
xylene
para
meta
per cent
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
Application number
GB140145A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Standard Oil Development Co
Original Assignee
Standard Oil Development Co
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Standard Oil Development Co filed Critical Standard Oil Development Co
Priority to GB140145A priority Critical patent/GB585076A/en
Publication of GB585076A publication Critical patent/GB585076A/en
Expired legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07CACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C7/00Purification; Separation; Use of additives
    • C07C7/14Purification; Separation; Use of additives by crystallisation; Purification or separation of the crystals

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Crystallography & Structural Chemistry (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)

Abstract

Meta-xylene in substantially pure from is recovered from a mixture of xylenes containing principally meta- and para-xylenes, by diluting said mixture with a relatively volatile inert diluent having a freezing point below -58.5 DEG C., cooling the diluted mixture suitably to below -58.5 DEG C., and removing crystals of para-xylene formed thereby, evaporating the diluent from the remaining liquid and again cooling the liquid, suitably to about -50 DEG to -56 DEG C. and removing the resulting meta-xylene crystals. The diluent may be used in the proportion of 1/5 to 2 volumes, or preferably 1/3 to 1 volume, per volume of mixed xylenes. Diluents specified are methyl, ethyl and isopropyl alcohols; acetone and methyl ethyl ketone; toluene; aliphatic hydrocarbons such as n-pentane, iso-pentane, pentenes, butenes, butanes, propane, propylene, ethane and ethylene. A suitable xylene mixture is obtained by fractionally distilling an aromatic fraction B.P. 136-144 DEG C. derived from petroleum oil, and collecting the meta/para fraction of B.P. 138 DEG to 141 DEG C. The crystallization process may be carried out in a jacketted kettle with cooling or by auto-refrigeration using the diluent, for example, liquid ethylene as the refrigerant. In a typical process, 1 volume of mixed xylenes (21 per cent. para, 71 per cent. meta, 8 per cent. other C8 aromatics) is mixed with 1 volume of n-pentane, cooled to -70 DEG C. and the para-xylene crystals so obtained removed; the filtrate is fractionally distilled to remove the diluent and the residue cooled to -52 DEG C. and then filtered, in this manner 70 per cent. of the p-xylene and 27 per cent. of the m-xylene present in the original mixture are recovered substantially pure.ALSO:Meta-xylene in substantially pure form is recovered from a mixture of xylenes containing principally meta- and para-xylenes by diluting said mixture with a relatively volatile inert diluent having a freezing point below - 58.5 DEG C., cooling the diluted mixture, suitably to a temperature below - 58.5 DEG C., removing crystals of para-xylene thereby formed, evaporating the diluent from the remaining liquid and again cooling the liquid, suitably to about - 50 DEG to - 56 DEG C. and removing the resulting metaxylene crystals. The diluent may be used in the proportions of 1/5 to 2 volumes or, preferably, 1/3 to 1 volume per volume of mixed xylenes. Diluents specified are methyl, ethyl or isopropyl alcohol; acetone and methyl ethyl ketone; toluene; aliphatic hydrocarbons such as n-pentane, isopentane, pentenes, butenes, butanes, propane, propylene, ethane and ethylene. A suitable xylene mixture may be obtained by fractionally distilling an aromatic fraction of boiling range 136 DEG to 144 DEG C. derived from petroleum oil distillation and collecting the meta/para xylene fraction boiling at 138 DEG to 141 DEG C. The crystallisation process may be carried out in a cooled kettle or by means of auto-refrigeration using the diluent, for example, liquid ethylene as the refrigerant. In a typical example, 1 volume of mixed xylenes (21 per cent para, 71 per cent meta, 8 per cent other C8 aromatics) together with 1 volume of n-pentane were cooled to - 70 DEG C., the para crystals which had formed were removed; the filtrate was then fractionally distilled to remove the n-pentane and the residue cooled to - 52 DEG C. and filtered; in this manner 70 per cent of the p-xylene and 27 per cent of the m-xylene present in the original mixture were recovered in pure form.
GB140145A 1945-01-17 1945-01-17 Process for the production of meta-xylene Expired GB585076A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB140145A GB585076A (en) 1945-01-17 1945-01-17 Process for the production of meta-xylene

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB140145A GB585076A (en) 1945-01-17 1945-01-17 Process for the production of meta-xylene

Publications (1)

Publication Number Publication Date
GB585076A true GB585076A (en) 1947-01-29

Family

ID=9721358

Family Applications (1)

Application Number Title Priority Date Filing Date
GB140145A Expired GB585076A (en) 1945-01-17 1945-01-17 Process for the production of meta-xylene

Country Status (1)

Country Link
GB (1) GB585076A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1034633B (en) * 1954-05-20 1958-07-24 Basf Ag Process for the decomposition of organic substance mixtures by fractional crystallization
DE972036C (en) * 1952-10-03 1959-05-14 Metallgesellschaft Ag Process for the separation of p-xylene from its technical mixtures

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE972036C (en) * 1952-10-03 1959-05-14 Metallgesellschaft Ag Process for the separation of p-xylene from its technical mixtures
DE1034633B (en) * 1954-05-20 1958-07-24 Basf Ag Process for the decomposition of organic substance mixtures by fractional crystallization

Similar Documents

Publication Publication Date Title
US2435792A (en) Chemical process
US2398526A (en) Isolation of para-xylene
US2521444A (en) Treatment of isomeric aromatic compounds
US2380019A (en) Azeotropic distillation
US2511711A (en) Process for separating a mixture of isomeric xylenes
US2567228A (en) Extractive distillation of closeboiling hydrocarbon fractions with hydrotropic solutions
US2528892A (en) Xylenes separation
US2530978A (en) Isolation of xylene isomers
GB585076A (en) Process for the production of meta-xylene
US2321117A (en) Purification of naphthalene
US2370948A (en) Styrene fractionation
US2370810A (en) Process for segregating valuable hydrocarbon constituents
US2799629A (en) Separation of hydrocarbons
US2438368A (en) Method of purifying benzene
US2367701A (en) Separation of hydrocarbons
US2642424A (en) Method of separating hydrocarbons
US2768222A (en) Separation of xylenes with antimony trichloride
US2874200A (en) Process for producing durene
US2393888A (en) Separation of xylenes
US2354895A (en) Purification of dicyclopentadiene
US2766303A (en) Production of cyclohexane
US2388429A (en) Separation of hydrocarbons
US2382119A (en) Process for extraction of hydrocarbons
US2449610A (en) Extractive distillation of butanes and butenes with acetone solvent
US2640804A (en) Purification of substituted aromatic compounds