Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C303/00—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides
  • C07C303/02—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides of sulfonic acids or halides thereof
  • C07C303/04—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides of sulfonic acids or halides thereof by substitution of hydrogen atoms by sulfo or halosulfonyl groups
  • C07C303/06—Preparation of esters or amides of sulfuric acids; Preparation of sulfonic acids or of their esters, halides, anhydrides or amides of sulfonic acids or halides thereof by substitution of hydrogen atoms by sulfo or halosulfonyl groups by reaction with sulfuric acid or sulfur trioxide

Definitions

• the present invention is directed to a method of making a synthetic petroleum sulfonate that is derived by sulfonating an alkylated aromatic compound made from a process of alkylating an aromatic compound with a mixture of olefins selected from olefins having from about 8 to about 100 carbon atoms in the presence of acidic ionic liquids.
• These sulfonates exhibit superior performance as enhanced oil recovery surfactants.
• U.S. Patent No. 5,994,602 discloses a process for the alkylation of aromatics by reacting an aromatic hydrocarbon with an olefin in the presence of an ionic liquid comprising (a) a compound of the formula R n MX 3 -H wherein R is a C1-C6 alkyl radical, M is aluminum or gallium, X is a halogen atom and n is O 5 1 or 2 and, (b) a hydrocarbyl substituted imidazolium halide or a hydrocarbyl substituted pyridinium halide wherein at least one of the said hydrocarbyl substituents in the imidazolium halide is an alkyl group having 1-18 carbon atoms.
• an ionic liquid comprising (a) a compound of the formula R n MX 3 -H wherein R is a C1-C6 alkyl radical, M is aluminum or gallium, X is a halogen atom and n is O 5 1
• U.S. Patent no 5,824,832 discloses a low temperature molten ionic liquid composition comprising a mixture of a metal halide and an alkyl-containing amine hydrohalide salt that can be used in linear alkylbenzene formation.
• U.S. Patent 5,731,101 discloses a low temperature molten ionic liquid composition comprising a mixture of a metal halide and an alkyl-containing amine hydrohalide salt is described which is useful as a catalyst and a solvent in alkylation, arylation, and polymerization reactions or as an electrolyte for batteries.
• Steichen et al., WO 98/50153 discloses a process related to in-situ formation of an ionic liquid catalyst for use in an ionic liquid-catalyzed chemical reaction.
• the in-situ formed liquid catalyst is applicable to a variety of ionic-liquid catalyzed chemical reactions including, for example, the alkylation of a benzene or phenol reagent, the oligomerization of an olefin, or the alkylation of a paraffin.
• the invention relates to the catalytic alkylation of an aromatic molecule with a suitable alkylating reagent (e.g., a C2 to C20, such as C4 to C 14 olefin or a halogenated alkane of similar chain length, using, as the catalyst, a composition which is liquid at low temperatures and which is formed in situ.
• a suitable alkylating reagent e.g., a C2 to C20, such as C4 to C 14 olefin or a halogenated alkane of similar chain length
• a process for preparing a synthetic petroleum sulfonate comprising (a) reacting at least one aromatic compound with a mixture of olefins selected from olefins having from about 8 to about 100 carbon atoms, in the presence of an acidic ionic liquid catalyst, wherein the resulting product comprises at least about 50 weight percent of a 1, 2, 4 tri- substituted aromatic compound or a 1, 2, 3 tri-substituted aromatic compound or mixtures thereof;
• the present invention relates to a process for preparing a sulfonated alkylated aromatic.
• Olefins refers to a class of unsaturated aliphatic hydrocarbons having one or more carbon-carbon double bonds, obtained by a number of processes. Those containing one double bond are called mono-alkenes, and those with two double bonds are called dienes, alkyldienes, or diolefins. Alpha olefins are particularly reactive because the double bond is between the first and second carbons. Examples are 1 -octene and 1-octadecene, which are used as the starting point for medium-biodegradable surfactants. Linear and branched olefins are also included in the defi nition of o lefins.
• Linear Olefins refers to olefins which are straight chain, non-branched hydrocarbons with at least one carbon-carbon double bond present in the chain.
• Double-Bond Isomerized linear Olefins refers to a class of linear olefins comprising more than 5% of olefins in which the carbon-carbon double bond is not terminal (i.e., the double bond is not located between the first and second carbon atoms of the chain).
• Partially branched linear olefins refers to a class of linear olefins comprising less than one alkyl branch per straight chain containing the double bond, wherein the alkyl branch may be a methyl group or higher. Partially branched linear olefins may also contain double-bond isomerized olefin.
• branched Olefins refers to a class of olefins comprising one or more alkyl branches per linear straight chain containing the double bond, wherein the alkyl branch may be a methyl group or higher.
• Ci 2 -C 30 + Normal Alpha Olefins This term defines a fraction of normal alpha olefins wherein the carbon numbers below 12 have been removed by distillation or other fractionation methods.
• One embodiment of the present invention is a process for preparing an alkylated aromatic compound, wherein said process comprises reacting at least one aromatic compound with a mixture of olefins selected from olefins having from about 8 carbon atoms to about 100 carbon atoms, in the presence of an acidic ionic liquid catalyst, wherein the resulting product comprises at least about 50 weight percent of a 1 , 2, 4 tri-substituted aromatic compound or a 1 , 2, 3 tri -substituted aromatic compound or mixtures thereof.
• At least one aromatic compound or a mixture of aromatic compounds may be used for the alkylation reaction in the present invention.
• the at least one aromatic compound or the aromatic compound mixture comprises at least one of monocyclic aromatics, such as benzene, toluene, xylene, cumene or mixtures thereof.
• the at least one aromatic compound or aromatic compound mixture may also comprise bi-cyclic and poly-cyclic aromatic compounds, such as naphthalenes.
• the at least one aromatic compound or aromatic compound mixture is xylene, including all isomers (i.e., meta -, ortho- and para-), a raffinate of xylene isomerization, and mixtures thereof.
• the at least one aromatic compound is ortho- • xylene.
• the at least one aromatic compound or the mixture of aromatic compounds employed in the present invention is prepared by methods that are well known in the art.
• the olefins employed in this invention may be linear, isomerized linear, branched or partially branched linear.
• the olefin may be a mixture of linear olefins, a mixture of isomerized linear olefins, a mixture of branched olefins, a mixture of partially branched linear or a mixture of any of the foregoing.
• the olefins may be derived from a variety of sources. Such sources include the normal alpha olefins, linear alpha olefins, isomerized linear alpha olefins, dimerized and oligomerized olefins, and olefins derived from olefin metathesis. Another source from which the olefins may be derived is through cracking of petroleum or Fischer- Tropsch wax. The Fischer-Tropsch wax may be hydrotreated prior to cracking. Other commercial sources include olefins derived from paraffin dehydrogenation and oligomerization of ethylene and other olefins, methanol-to-olefin processes (methanol cracker) and the like.
• the olefins may also be substituted with other functional groups, such as hydroxy groups, carboxylic acid groups, heteroatoms, and the like, provided that such groups do not react with the acidic ionic liquid catalyst.
• the mixture of olefins is selected from olefins with carbon numbers ranging from about 8 carbon atoms to about 100 carbon atoms.
• the mixture of olefins is selected from olefins with carbon numbers ranging from about 10 to about 80 carbon atoms, more preferred from about 14 to about 60 carbon atoms.
• the mixture of olefins is selected from linear alpha olefins or isomerized olefins containing from about 8 to about 100 carbon atoms. More preferably, the mixture of olefins is selected from linear alpha olefins or isomerized olefins containing from about 10 to about 80 carbon atoms. Most preferably, the mixture of olefins is selected from linear alpha olefins or isomerized olefins containing from about 14 to about 60 carbon atoms.
• the mixture of olefins contains a distribution of carbon atoms that comprise from about 40 to about 90 percent Ci 2 to C 20 and from about 4 percent to about 15 percent C32 to C 5 8. More preferably, the distribution of carbon atoms comprises from about 50 to. about 80 percent Ci 2 to C 20 and from about 4 percent to about 15 percent C 32 to Cj 8 .
• the mixture of branched olefins is preferably selected from polyolefins which may be derived from C 3 or higher monoolefins (i.e., propylene oligomers, butyl enes oligomers, or co-oligomers etc.).
• the mixture of branched olefins is either propylene oligomers or butylenes oligomers or mixtures thereof. Normal Alpha Olefins
• the mixture of linear olefins that may be used for the alkylation reaction is a mixture of normal alpha olefins selected from olefins having from about 8 to about 100 carbon atoms per molecule. More preferably the normal alpha olefin mixture is selected from olefins having from about 10 to about 80 carbon atoms per molecule. Most preferably, the normal alpha olefin mixture is selected from olefins having from about 12 to about 60 carbon atoms per molecule. An especially preferred range is from about 14 to about 60.
• the normal alpha olefins are isomerized using at least one of two types of acidic catalysts, solid or liquid.
• a solid catalyst preferably has at least one metal oxide and an average pore size of less than 5.5 angstroms. More preferably, the solid catalyst is a molecular sieve with a one- dimensional pore system, such as SM-3, MAPO-1 1, SAPO-1 1, SSZ-32, ZSM-23, MAPO-39, SAPO-39, ZSM-22 or SSZ-20.
• Other possible acidic solid catalysts useful for isomerization include ZSM-35, SUZ-4, NU-23, NU-87 and natural or synthetic ferrierites.
• a liquid type of isomerization catalyst that can be used is iron pentacarbony (Fe(CO) 5 ).
• the process for isomerization of normal alpha olefins may be carried out in batch or continuous mode.
• the process temperatures may range from about 5O 0 C to about 250 0 C..
• a typical method used is a stirred autoclave or glass flask, which may be heated to the desired reaction temperature.
• a continuous process is most efficiently carried out in a fixed bed process. Space rates in a fixed bed process can range from 0.1 to 10 or more weight hourly space velocity.
• the isomerization catalyst is charged to the reactor and activated or dried at a temperature of at least 150°C under vacuum or flowing inert, dry gas.
• the temperature of the isomerization catalyst is adjusted to the desired reaction lemperature and a flow of the olefin is introduced into the reactor.
• the reactor effluent containing the partially-branched, isomerized olefins is collected.
• the resulting partially-branched, isomerized olefins contain a different olefin distribution (i.e., alpha olefin, beta olefin; internal olefin, tri-substituted olefin, and vinylidene olefin) and branching content that the unisomerized olefin and conditions are selected in order to obtain the desired olefin distribution and the degree of branching.
• the acidic ionic liquid catalyst is composed of two components which form a complex.
• the first component of the catalyst will typically comprise a compound selected from the group consisting of aluminum halide, alkyl aluminum halide, gallium halide, and alkyl gallium halide.
• Especially preferred for the first component is aluminum halide or alkyl aluminum halide.
• aluminum trichloride may be used as the first component for preparing the catalyst used in practicing the present invention.
• the second component making up the ionic liquid catalyst is an organic salt or mixture of salts.
• These salts may be characterized by the general formula Q + A " , wherein Q + is an ammonium, phosphonium, or sulfonium cation and A " is a negatively charged ion such as Cl “ , Br “ , ClO 4 “ , NO 3 “ , BF 4 “ , BCL 4 “ , PF 6 “ , SbF 6 “ .
• Preferred for use as the second component are those quaternary ammonium halides containing one or more alkyl moieties having from about 1 to about 9 carbon atoms, such as, for- example, trimethylamine hydrochloride, methyltributylammonium, and 1 - • butylpyridinium, or hydrocarbyl substituted imidazolium halides, such as for example, 1 -ethyl-3-methyl-imidazolium chloride.
• the presence of the first component should give the ionic liquid a Lewis acidic character. Generally, the greater the mole ratio of the first component to the second component, the greater the acidity of the ionic liquid mixture.
• aluminum trichloride and trimethylamine hydrochloride are used as the first and second components, respectively, of the acidic ionic liquid catalyst, they preferably will be present in a mole ratio of from greater than about 1 : 1 to about 2: 1.
• the alkylation process may be carried out in a batch or continuous process.
• the acidic ionic liquid catalyst may be recycled when used in a continuous process or batch process.
• the alkylation process is carried out by charging a hydrocarbon feed comprising an aromatic compound or a mixture of aromatic compounds, a mixture of olefin compounds and an acidic ionic liquid catalyst to a reaction zone in which agitation is maintained.
• the resulting mixture is held in the alkylation zone under alkylation conditions for a time sufficient to allow substantial conversion (i.e., at least 80 mole% of the olefin has reacted) of the olefin to aromatic alkylate.
• the reaction mixture is removed from the alkylation zone and fed to a liquid-liquid separator to allow hydrocarbon products to separate from the acidic ionic liquid catalyst.
• the acidic ionic liquid catalyst is recycled to the reactor in a closed loop cycle.
• the hydrocarbon product is further treated to remove excess un-reacted aromatic compounds and optionally olefinic compounds from the desired alkylate product.
• the excess aromatic compounds are also recycled to the reactor.
• reactor configurations may be used for the reactor zone. These include, but are not limited to, batch and continuous stirred tank reactors, reactor riser configurations, ebulating bed reactors, and other reactor configurations that are well known in the art. Many such reactors are known to those skilled in the art and are suitable for the alkylation reaction. Agitation is critical for the alkylation reaction and can be provided by rotating impellers, with or without baffles, static mixers, kinetic mixing in risers, or any other agitation devices that are well known in the art.
• the alkylation process may be carried out at temperatures from about 0 0 C to about 100°C.
• the process is carried out under sufficient pressure that a substantial portion of the feed components remain in the liquid phase. Typically, a pressure of 0 to 150 psig is satisfactory to maintain feed and products in the liquid phase.
• the residence time in the reactor is a time that is sufficient to convert a substantial portion of the olefin to alkylate product.
• the time required is from about 30 seconds to about 30 minutes.
• a more precise residence time may be determined by those skilled in the art using batch stirred tank reactors to measure the kinetics of the alkylation process.
• the at least one aromatic compound or mixture of aromatic compounds and the mixture of olefins may be injected separately into the reaction zone or may be mixed prior to injection. Both single and multiple reaction zones may be used with the injection of the aromatic compounds and the mixture of olefins into one, several, or all reaction zones. The reaction zones need not be maintained at the same process conditions.
• the hydrocarbon feed for the alkylation process may comprise a mixture of aromatic compounds and a mixture olefins in which the molar ratio of aromatic compounds to olefins is from about 0.5:1 to about 50:1 or more. In the case where the molar ratio of aromatic compounds to olefin is > 1.0. there is an excess amount of aromatic- compounds present. Preferably an excess of aromatic compounds is used to increase reaction rate and improve product selectivity. When excess aromatic compounds are used, the excess un-reacted aromatic in the reactor effluent can be separated, e.g. by distillation, and recycled to the reactor.
• One embodiment of the present invention is a continuous process with closed loop catalyst recycle.
• a hydrocarbon feed comprising aromatic compound(s) or a mixture of aromatic compounds and a mixture of olefin(s) is charged continuously and pumped to a reactor .
• the aromatic compound(s) and mixture of olefin(s) may be charged by separate lines and pumped to another line .
• fresh acidic ionic liquid catalyst is charged and pumped to a reactor .
• the hydrocarbon feed and acidic ionic liquid catalyst are maintained in a reactor with agitation under alkylation process conditions, for a sufficient time in order for a substantial amount of the mixture of olefins in the feed charge to react and form an aromatic alkylate compound.
• the major portion of this process is thus operated under conditions of catalyst recycle, under which no fresh catalyst is added or only a small amount of make-up catalyst is added.
• the hydrocarbon product stream containing the aromatic alkylate compound and excess un-reacted aromatic is charged to a product separation section via a line .
• product separation excess aromatic compounds are distilled off and returned to the reactor , leaving a tri- substituted alkylated aromatic compound.
• the product of the presently claimed invention is a tri-substituted alkylated aromatic compound.
• the resulting product comprises at least about 50 weight percent of a 1, 2, 4 tri-substituted aromatic compound or a 1, 2, 3 tri-substituted aromatic compound or mixtures thereof. More preferably, the resulting product comprises at least about 80 weight percent, even mor preferably at least about 95 weight percent, of a 1, 2, 4 tri-substituted aromatic compound or a 1, 2, 3 tri- substituted aromatic compound or mixtures thereof. Most preferably, the resulting product comprises at least about 98 weight percent of a 1, 2, 4 tri-substituted aromatic compound or a 1 , 2, 3 tri-substituted aromatic compound or mixtures thereof.
• the ratio of the 1, 2, 4 tri-substituted aromatic to the 1 , 2, 3 tr ⁇ - substituted aromatic is at least 50:50. More preferably, the ratio is at least 80:20. Even more preferably, the ratio is at least 95:5. And, most preferably, the ratio is at least 98:2.
• the present invention produced unexpected results when an aromatic compound, such as o-xylene, was alkylated with a mixture of olefins in the presence of an acidic ionic liquid, including chloroaluminate ionic liquid catalysts.
• an aromatic compound such as o-xylene
• alkylation of an aromatic compound, such as o-xylene could be carried out using a mixture of olefins selected from olefins having a carbon range of from about C12 to about C30+ of normal alpha olefins under catalyst recycle conditions for a total production time of about 300 hours.
• the product prepared by the process described herein i.e., alkylated orthoxylene: 1,2,4 trisubstituted alkylbenzene; 1 ,2,3 trisubstituted alkylbenzene and mixtures thereof
• alkylated orthoxylene 1,2,4 trisubstituted alkylbenzene; 1 ,2,3 trisubstituted alkylbenzene and mixtures thereof
• Sulfonation of the alkylaromatic such as alkylorthoxylene
• the sulfonation reaction is typically carried out in a continuous falling film tubular reactor maintained at about 55°C.
• the alkylorthoxylene is placed in the reactor along with the sulfur trioxide diluted with air, sulfuric acid, chlorosulfonic acid or sulfamic acid, thereby producing alkylorthoxylene sulfonic acid.
• the alkylorthoxylene is sulfonated with sulfur trioxide diluted with air.
• the charge mole ratio of sulfur trioxide to alkylate is maintained at about 0.8 to 1.1: 1.
• Neutralization of the alkylaromatic sulfonic acid may be carried out in a continuous or batch process by any method known to a person skilled in the art to produce alkylaromatic sulfonates.
• an alkylaromatic sulfonic acid is neutralized with a source of alkali or alkaline earth metal.
• the alklyaromatic sulfonic acid is neutralized with an alkaline earth metal hydroxide, such as but not limited to, calcium hydroxide or magnesium hydroxide.
• Anhydrous aluminum trichloride and methyltributylammonium chloride were dried overnight under vacuum at 100 0 C.
• the preparation of the ionic liquid catalyst was carried out in a dry box. 550.6 grams of methyltributylammonium chloride was added to a beaker which was equipped with a magnetic stirring bar. 622.7 grams of anhydrous aluminum chloride was added to a second beaker. With the magnetic stirred activated, small portions of the solid aluminum chloride were slowly added to the beaker of methyltributylammonium chloride. As aluminum chloride was added, heat evolution took place and the reaction mixture began to turn "pasty" and then partially liquid. The rate of addition of aluminum chloride was slowed to moderate the temperature increase in the beaker. As more aluminum chloride was added, more liquid was formed and eventually the reaction mixture began to stir freely.
• reaction mixture After the addition entire amount of aluminum trichloride, the reaction mixture was allowed to cool to ambient temperature and was stirred overnight. The next morning the reaction mixture was filtered through a sintered glass filter which had been dried at 130 C. The final filtered ionic liquid catalyst was stored under nitrogen in a glass bottle.
• the olefin used to make this feed was a commercial C
• the mixture of Ci 2 - C 3 0+ nao comprised 79 wt% C12-C 20 olefins and 4 wt% C 32 -C 58 olefins. At the lowest boiling point, 20 wt% of the olefin was removed by distillation prior to making the alkylation feed mixture.
• the feed mixture was dried over 4A molecular sieves and stored under dry nitrogen during use. Because of the waxy nature of the alpha olefin, the alkylation feed mixture was heated to 50 0 C with stirring to keep all the olefin in solution. O-Xylene was also dried over 4A molecular sieves and stored under dry nitrogen during use.
• a mixture of 300 rnL of ionic liquid catalyst of Example 1 and 400 mL of o-xylene was prepared and was stored under dry nitrogen during use.
• o-xylene was pumped at a nominal rate of approximately 120 g/hour into the reactor, through the back pressure regulator into the liquid-liquid separator and finally into a hydrocarbon product reservoir.
• the reactor was stirred at 600 RPM and heated to 40 0 C. Pressure was increased by means of the back pressure regulator to about 50 psig.
• the ionic liquid catalyst/o-xylene mixture was pumped into the reactor at a nominal rate of 20 grams per hour.
• the o-xylene flow was stopped and the alkylation feed mixture was pumped into the reactor at approximately 120 g/hour.
• the flow of fresh catalyst was stopped and the flow of recycled catalyst was started at the same nominal catalyst flow rate. This time marked the start of run.
• product samples were collected in two ways. First, small samples were obtained periodically from a sample valve located in the line leading out from the back pressure regulator. Second ⁇ the bulk liquid product was collected in large product cans which were each changed at 12 hours of operation. Products were analyzed by gas chromatography and conversion was measured from the disappearance of olefin in the gas chromatograms of the products.
• catalytic operation was occasionally stopped for maintenance on pumps or for addition of new containers of alkylation feed. Not including the time when the operation was temporarily stopped for maintenance, the unit operated to produce aromatic alkylate with a closed catalyst recycle loop for a total of 191 hours.
• the mixture of olefins comprised 71 wt% C12-C20 nao and 5 wt% C 32 -C 58 nao.
• the temperature of the reaction mixture increased from 20 0 C to 53 0 C and was allowed to cool to 31 °C with stirring.
• the reaction mixture was transferred to a separatory funnel and the ionic liquid catalyst was separated from the organic mixture.
• a C 12 - 3 0+ o-Xylene Alkylate similar to that prepared in Examples 2, 3, and 4, above, was sulfonated by a concurrent stream of sulfur trioxide (SO 3 ) and air in a tubular reactor (approximately, 2 meters long, 1 cm inside diameter) in a down flow mode using the following conditions: Reactor Temperature: 65°C
• the SO 3 was generated by passing the mixture of oxygen and sulfur dioxide (SO 2 ) through a catalytic furnace containing vanadium oxide (V 2 O5).
• 2 - 30+ o-Xylene Sulfonic Acid produced had the following properties: 3.95 wt% Ca as Sulfonate and 0.82 wt% H 2 SO 4 .

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