US3793187A - Process for removing carbonyl compounds from hydrocarbons - Google Patents

Process for removing carbonyl compounds from hydrocarbons Download PDF

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Publication number
US3793187A
US3793187A US00277021A US3793187DA US3793187A US 3793187 A US3793187 A US 3793187A US 00277021 A US00277021 A US 00277021A US 3793187D A US3793187D A US 3793187DA US 3793187 A US3793187 A US 3793187A
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Prior art keywords
hydrazinium
hydrocarbons
carbonyl
hydrocarbon
percent
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Expired - Lifetime
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US00277021A
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English (en)
Inventor
H Marx
H Scherb
B Schleppinghoff
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Erdoelchemie GmbH
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Erdoelchemie GmbH
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Priority claimed from DE19712141469 external-priority patent/DE2141469C3/de
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    • 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
    • C10G29/00—Refining of hydrocarbon oils, in the absence of hydrogen, with other chemicals
    • C10G29/06—Metal salts, or metal salts deposited on a carrier
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C7/00—Purification; Separation; Use of additives
    • C07C7/10—Purification; Separation; Use of additives by extraction, i.e. purification or separation of liquid hydrocarbons with the aid of liquids
    • 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
    • C10G21/00—Refining of hydrocarbon oils, in the absence of hydrogen, by extraction with selective solvents
    • C10G21/06—Refining of hydrocarbon oils, in the absence of hydrogen, by extraction with selective solvents characterised by the solvent used
    • C10G21/08—Inorganic compounds only

Definitions

  • This invention relates to a process for separating carbonyl compounds from hydrocarbons or hydrocarbon mixtures by treating the hydrocarbons or hydrocarbon mixtures in the liquid-liquid, two-phase system with an aqueous solution of a hydrazinium compound and subsequently separating the carbonyl-free hydrocarbon phase from the aqueous phase.
  • the steam cracking of light petrols is accompanied by secondary reactions which are evidently attributable to the chemical mixture also contains carbonyl compounds, especially aldehydes and ketones (hereinafter referred to as carbonyl compounds such as ethanal, propanal, acetone and others which, because of their boiling point, enter the C or C -fraction during separation of the cracking gases.
  • carbonyl compounds especially aldehydes and ketones (hereinafter referred to as carbonyl compounds such as ethanal, propanal, acetone and others which, because of their boiling point, enter the C or C -fraction during separation of the cracking gases.
  • the carbonyl content depends on whether the light petrol is cracked at lower or high temperatures. Normally the content varies within the range of from a few hundred to more than 1,000 ppm, based on the hydrocarbons.
  • carbonyl compounds can be fored in hydrocarbons as derivatives of compounds which are formed autoxidation of unsaturated hydrocarbons.
  • the carbonyl compounds cannot be separated off by distillation because it is particularly the carbonyls of low molecular weight, such as ethanal, propanal and acetone, which from azeotropes with numerous hydrocarbons, for example ethanol with 1,3-butadiene or acetone with isoprene, cyclopentadiene and piperylene, cf. Azeotropic Data, ACS Monography No. 6 Washington 1952.
  • liquid hydrocarbons or hydrocarbon mixtures containing carbonyl compounds as impurities in quantities of up to about 5,000 ppm can be purified in a simple and economic manner by subjecting the hydrocarbon or the hydrocarbon mixture to a liquid-liquid extraction with an aqueous solution of a hydrazinium compound and separating the puriified hydrocarbon phase from the aqueous phase.
  • FIG. 1 is a diagrammatic view of apparatus suitable for carying out the process of the invention continuously; and I FIG. 2 is a graph of four curves showing residual carbonyl content as described in Examples 2-5 herein.
  • carbonyl impurities can be removed from any hydrocarbon or hydrocarbon mixture which forms two liquid phases with the aqueous hydrazinium compound solution under the conditions according to the invention, for example from saturated and unsaturated hydrocarbons, from the C and C -fraction which accumulate during the cracking of light petrol, such as butadiene, butenes pentanes, pentenes, isoamylenes, isoprene, piperylene, cyclopentadiene or from mixtures of these compounds.
  • saturated and unsaturated hydrocarbons from the C and C -fraction which accumulate during the cracking of light petrol, such as butadiene, butenes pentanes, pentenes, isoamylenes, isoprene, piperylene, cyclopentadiene or from mixtures of these compounds.
  • Hydrazinium compounds suitable for use in the process according to the invention include compounds of the general formula N I-I X (wherein X is a monovalent anion) which are soluble in water.
  • Specific examples of such hydrazinium compounds are hydrazinium sulphate, hydrazium chloride and preferably hydrazinium hydroxide (hydrazine hydrate).
  • the hydrazinium compounds are used in an aqueous solution.
  • the molar ratio of the hydrazinium compound to the carbonyls should preferably amount to at least 1 l, but more preferably to within the range 3 1 TO 10 l.
  • the hydrazinium compounds are dissolved in water to form a 0.5 to 10 percent by weight solution and preferably a l to 5 by weight solution.
  • the extraction temperatures can be varied within a relatively wide range, the lower limit being determined by the freezing point of the washing solution.
  • the upper limit to the temperature range is imposed solely by the requirement that two liquid phases should exist alongside one another. In other words the temperature range rises with increased pressure.
  • the reaction is carried out at a temperature in the range of from 5 to 50C under a pressure of from 0.5 to 5 bars, and preferably at a temperature of from 10 to 30C under normal pressure.
  • a single wash with a hydrazine hydrate solution is sufficient to reduce the carbonyl content from up to several thousand ppm to considerably below ppm, based on the hydrocarbon or the hydrocarbon mixture.
  • a simple subsequent wash with water is required to remove traces of hydrazinium compound dissolved in the hydrocarbons to below the detection limit.
  • the process according to the invention can be used for purifying hydrocarbons by intensively contacting in a container a bath of the hydrocarbon or hydrocarbon mixture to be purified with the washing solution and, thereafter, optionally washing the hydrocarbon phase with water to remove traces of dissolved hydrazinium compound following phase separation.
  • the process is carried out continuously.
  • any type of conventional mixer-separators can be used for intermixing the two liquid phases and for subsequently separating them again.
  • the hydrocarbons purified by the process according to the invention are washed with water and then further processed.
  • washing with water can take the form of, for example, a countercurrent wash.
  • the continuous procedure enables the hydrazinium compound in the washing solution to be maintained in the required concentration to remove the carbonyl compounds by in the lower part of the mixing apparatus 6.
  • the intensively mixed liquid streams from the feed pipe 5 and the upper part of the mixing apparatus are guided into the lateral pipe 11 of the mixing apparatus 6.
  • the mixed phase flows through the lateral pipe through a packed layer into the upper part of the mixing apparatus. From there, part of the mixed phase flows through a pipe 8 into a settling chamber 9, whilst the rest of the mixed phase is drawn downwards into the mixing pump 7 back to the mixing zone.
  • the upper part of the settling chamber 9 is filled with a packing to promote phase separation.
  • the purified hydrocarbon phase separated off is optionally washed by being delivered via a pipe 10 in countercurrent to a stream of water.
  • the lower part of the settling chamber 9 acts as a reservoir for the recycled aqueous solution of the hydrazinium compound. This solution is again delivered to the mixing apparatus through a pipe 3 and can be replaced at any point by removing a fraction and introducing fresh solution.
  • the process according to the invention has a number of advantages. For example, it enables reaction conditions such as temperature and pressure, under which the washing is carried out to be adapted to particular requirements.
  • the starting material can be directly subjected to the process according to the invention in the liquid phase in an economically favourable manner.
  • Another advantage is that the process of the invention functions without any loss of hydrocarbons because the hydrocarbons themselves do not react or are not prompted to react, for example to polymerise, with the substances of the washing solution.
  • EXAMPLE 1 Three-hundred ml of a hydrocarbon mixture of which substantially'90% by weight consisted of cisand trans-1,3-pentadiene and substantially 10 percent by weight of other C -paraffins, -olefins, -diolefins and -acetylenes, was treated with aqueous hydrazinium hydroxide solution in accordance with Table l in a vessel mounted on a vibration machine.
  • the hydrocarbon mixture had an initial carbonyl content of 2,100 ppm.
  • the residual contents of carbonyl compounds in the hydrocarbon batches treated and the level of reduction (content of carbonyl compounds in the starting material/carbonyl compounds in the purified mixture), are shown in Table 1.
  • the contents of carbonyl compounds were determined with hydroxylamine hydrochloride in accordance with an ASTM method, and are based on ethanal.
  • the mixed phase was delivered from the upper part of the mixing apparatus through the pipe 8 into a settling chamber 9, the lower part of which acted as a reservoir for the washing solution.
  • the clear hydrocarbon phase was run off from the upper part of the settling chamber through pipe 10 and subjected to a countercurrent wash.
  • the hydrazinium hydroxide solution (1,300 ml in the system) was recycled.
  • curve 1 shows the residual carbonyl content in the hydrocarbon mixture in dependence upon the throughput.
  • the hydrazinium compound content of the purified hydrocarbon phase was below the detection limit of 1 ppm.
  • EXAMPLE 3 As in Example 2, 500 ml/h of a hydrocarbon mixture with the same composition as in Example 1 (2,100 ppm of carbonyl compounds) were treated with 425 ml/h of a 2 percent aqueous hydrazinium hydroxide solution. The reaction conditions were the same as in Example 2. The residual carbonyl contents in the purified product are shown in FIG. 2, curve 2.
  • EXAMPLE 4 One thousand ml/h of the same hydrocarbon mixture as in Example 1, except that it had a carbonyl compound content of only 181 ppm, were treated as in Example 2 with 330 ml/h of a 2 percent aqueous solution of hydrazinium hydroxide.
  • FIG. 2 curve 3 shows the residual carbonyl content in the purified hydrocarbon mixture.
  • EXAMPLE 5 One thousand ml/h of a C -hydrocarbon fraction of the kind obtained during the cracking of light petrol which consisted of (in percent by weight 30.9 percent of paraffins, 30.] percent of olefins, 38.2 percent of diolefins and 0.7 percent of acetylenes, and which contained 1,242 ppm of carbonyl compounds was treated as in Example 2 with 330 ml/h of a 2 percent aqueous hydrazinium hydroxide solution under normal pressure at a temperature of 20 C. Thereafter, the purified C fractions had a carbonyl content of only 50 60 ppm (see FIG. 2, curve 4).
  • EXAMPLE 6 As in Example 2, 500 ml/h of 99.9 percent n-hexane which was contaminated by 1,200 ppm of acetone, were combined and treated with 425 ml/h of a 5 percent aqueous solution of hydrazinium hydroxide. It was not possible to detect any more acetone in the purified n-hexane by the method of detection described in Example 1.
  • EXAMPLE 7 The process according to the invention was carried out in a continuous countercurrent extraction installation (rotating-plates system with an effective extraction zone of 3 metres) at a rotational speed of 520 rpm.
  • 150 kg/h of a crude cyclopentene fraction consisting of 95 percent of cyclopentene, 3.2 percent of cyclopentane, l.8 percent of C -hydrocarbons and 423 ppm of carbonyl compounds were guided in countercurrent to 30 kg/h of a 4 percent aqeuous solution of hydrazinium hydroxide. Extraction was carried out at room temperature and normal pressure, the washing solution being dispersed in the hydrocarbon phase.
  • the purified crude cyclopentene thus obtained has a residual carbonyl content of 18 ppm.
  • Process for purifiying liquid hydrocarbons containing aldehydes and ketones as impurities in quantities of up to about 5,000 ppm. which comprises extracting said hydrocarbons with an aqueous solution of a hydrazinium compound having the formula N H X, wherein X is a monovalent anion, and separating the purified hydrocarbon phase.
  • hydrazinium compound is selected from the group of hydrazinium sulphate, hydrazinium chloride and hydrazine hydrate.

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  • Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Water Supply & Treatment (AREA)
  • Inorganic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
US00277021A 1971-08-19 1972-08-01 Process for removing carbonyl compounds from hydrocarbons Expired - Lifetime US3793187A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19712141469 DE2141469C3 (de) 1971-08-19 Verfahren zur Entfernung von Carbonylverbindungen aus Kohlenwasserstoffen

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US (1) US3793187A (fr)
JP (1) JPS5212681B2 (fr)
BE (1) BE787760A (fr)
FR (1) FR2149569B1 (fr)
GB (1) GB1368172A (fr)
NL (1) NL154484B (fr)

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4673489A (en) * 1985-10-10 1987-06-16 Betz Laboratories, Inc. Method for prevention of fouling in a basic solution by addition of specific nitrogen compounds
US4952301A (en) * 1989-11-06 1990-08-28 Betz Laboratories, Inc. Method of inhibiting fouling in caustic scrubber systems
WO1992013929A1 (fr) * 1991-02-08 1992-08-20 Ashchem I.P., Inc. Procede inhibant la formation de salissures
US5194143A (en) * 1991-11-18 1993-03-16 Betz Laboratories, Inc. Method for inhibiting fouling in caustic scrubber systems
US5220104A (en) * 1992-06-15 1993-06-15 Betz Laboratories, Inc. Method for the prevention of fouling in a caustic solution
US5264114A (en) * 1991-03-25 1993-11-23 Phillips Petroleum Company Hydrocarbon treating process
US5470457A (en) * 1994-06-17 1995-11-28 Phillips Petroleum Company Stabilization of hydrocarbons by the addition of hydrazine
WO2000069466A1 (fr) * 1999-05-12 2000-11-23 Kurokawa, Kiyoshi Agent de piegeage de composes carbonyles sanguins
EP1354863A1 (fr) * 2002-04-18 2003-10-22 Haldor Topsoe A/S Procédé continu pour l'élimination d'eau de courants d'hydrocarbures
US20040015032A1 (en) * 2002-07-16 2004-01-22 Ramaswamy Perumangode Neelakantan Method for reducing foam in a primary fractionator
US6919326B1 (en) 1998-08-24 2005-07-19 Toshio Miyata Carbonyl-stress improving agent and peritoneal dialysate
US20050205468A1 (en) * 2004-02-13 2005-09-22 Renaud Cadours Method for processing a natural gas with extraction of the solvent contained in the purified natural gas
US20050224394A1 (en) * 2002-06-26 2005-10-13 Dorf Ketal Chemicals India Pvt. Ltd. Method of removal of carbonyl compounds along with acid gases from cracked gas in ethylene process
US8118995B2 (en) 2009-03-31 2012-02-21 General Electric Company Process for inhibiting fouling in hydrocarbon processing

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2926750A (en) * 1955-09-06 1960-03-01 Phillips Petroleum Co Unsymmetrical dimethyl hydrazine as a solvent for acetylene
US2966455A (en) * 1957-08-14 1960-12-27 Sun Oil Co Refining hydrocarbons with hydrazines and hydrogenation catalysts
US3308201A (en) * 1966-03-08 1967-03-07 Petro Tex Chem Corp Purification of hydrocarbons

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2926750A (en) * 1955-09-06 1960-03-01 Phillips Petroleum Co Unsymmetrical dimethyl hydrazine as a solvent for acetylene
US2966455A (en) * 1957-08-14 1960-12-27 Sun Oil Co Refining hydrocarbons with hydrazines and hydrogenation catalysts
US3308201A (en) * 1966-03-08 1967-03-07 Petro Tex Chem Corp Purification of hydrocarbons

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4673489A (en) * 1985-10-10 1987-06-16 Betz Laboratories, Inc. Method for prevention of fouling in a basic solution by addition of specific nitrogen compounds
US4952301A (en) * 1989-11-06 1990-08-28 Betz Laboratories, Inc. Method of inhibiting fouling in caustic scrubber systems
US5213678A (en) * 1991-02-08 1993-05-25 Ashchem I.P., Inc. Method for inhibiting foulant formation in organic streams using erythorbic acid or oximes
AU650213B2 (en) * 1991-02-08 1994-06-09 Ashchem I.P., Inc. Method for inhibiting foulant formation
WO1992013929A1 (fr) * 1991-02-08 1992-08-20 Ashchem I.P., Inc. Procede inhibant la formation de salissures
US5264114A (en) * 1991-03-25 1993-11-23 Phillips Petroleum Company Hydrocarbon treating process
US5194143A (en) * 1991-11-18 1993-03-16 Betz Laboratories, Inc. Method for inhibiting fouling in caustic scrubber systems
US5220104A (en) * 1992-06-15 1993-06-15 Betz Laboratories, Inc. Method for the prevention of fouling in a caustic solution
US5470457A (en) * 1994-06-17 1995-11-28 Phillips Petroleum Company Stabilization of hydrocarbons by the addition of hydrazine
US5672793A (en) * 1994-06-17 1997-09-30 Phillips Petroleum Company Stabilization of hydrocarbons by the addition of hydrazine
US7745613B2 (en) 1998-08-24 2010-06-29 Toshio Miyata Method for preparing peritoneal dialysate
US20050267045A1 (en) * 1998-08-24 2005-12-01 Toshio Miyata Method for preparing peritoneal dialysate
US7297689B2 (en) 1998-08-24 2007-11-20 Kiyoshi Kurokawa Method for preparing peritoneal dialysate
US6919326B1 (en) 1998-08-24 2005-07-19 Toshio Miyata Carbonyl-stress improving agent and peritoneal dialysate
US20070020341A1 (en) * 1998-08-24 2007-01-25 Toshio Miyata; Kiyoshi Kurokawa; And Tokai University Educational System Method for preparing peritoneal dialysate
WO2000069466A1 (fr) * 1999-05-12 2000-11-23 Kurokawa, Kiyoshi Agent de piegeage de composes carbonyles sanguins
US20030199723A1 (en) * 2002-04-18 2003-10-23 Hommeltoft Sven Ivar Continuous process for the removal of water from a hydrocarbon stream
US7077950B2 (en) 2002-04-18 2006-07-18 Haldor Topsoe A/S Continuous process for the removal of water from a hydrocarbon stream
EP1354863A1 (fr) * 2002-04-18 2003-10-22 Haldor Topsoe A/S Procédé continu pour l'élimination d'eau de courants d'hydrocarbures
US20050224394A1 (en) * 2002-06-26 2005-10-13 Dorf Ketal Chemicals India Pvt. Ltd. Method of removal of carbonyl compounds along with acid gases from cracked gas in ethylene process
US7575669B2 (en) 2002-06-26 2009-08-18 Dorf Ketal Chemicals, Llc Method of removal of carbonyl compounds along with acid gases from cracked gas in ethylene process
US20040015032A1 (en) * 2002-07-16 2004-01-22 Ramaswamy Perumangode Neelakantan Method for reducing foam in a primary fractionator
US7906012B2 (en) 2002-07-16 2011-03-15 Dorf Ketal Chemicals India Pvt. Ltd. Method for reducing foam in a primary fractionator
US20050205468A1 (en) * 2004-02-13 2005-09-22 Renaud Cadours Method for processing a natural gas with extraction of the solvent contained in the purified natural gas
US7470829B2 (en) * 2004-02-13 2008-12-30 Institut Francais Du Petrole Method for processing a natural gas with extraction of the solvent contained in the purified natural gas
US8118995B2 (en) 2009-03-31 2012-02-21 General Electric Company Process for inhibiting fouling in hydrocarbon processing

Also Published As

Publication number Publication date
FR2149569B1 (fr) 1976-08-13
FR2149569A1 (fr) 1973-03-30
NL154484B (nl) 1977-09-15
GB1368172A (en) 1974-09-25
JPS4829702A (fr) 1973-04-19
NL7211274A (fr) 1973-02-21
BE787760A (fr) 1973-02-19
JPS5212681B2 (fr) 1977-04-08
DE2141469A1 (de) 1973-02-22
DE2141469B2 (de) 1976-08-26

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