Abstract: A process for removing dimethyl ether (DME) and methanol impurities from C.sub.4 hydrocarbon stream without substantial loss of C.sub.4 hydrocarbons by fractionating a C.sub.4 hydrocarbon stream containing DME and methanol at low levels, e.g., less than 5 wt. % to produce an overhead of about 20 to 40 volume % of the C.sub.4 stream, condensing the overhead, contacting the condensed overhead with about 1 to 5 volumes of water, thereby removing a portion of the DME and methanol from the C.sub.4 stream, returning substantially all of the C.sub.4 stream, except the small amount solubilized in the water, to the fractionation and flashing the solubilized DME and hydrocarbons from the water. The fractionation and extraction are preferably carried out at elevated pressures, e.g., 200 to 300 psig to avoid refrigeration of the overhead condensation. The flashing of the DME and hydrocarbons is carried out by reducing the pressure on the water, e.g. atmospheric pressure at a temperature in the range of 20.degree. C.

Abstract: A method and apparatus for conducting a catalytic distillation process is provided which allows for maintaining a liquid level in selected portions of the catalyst bed. Three particular processes disclosed are the production of methyl tertiary butyl ether, tertiary butyl alcohol and cumene.

Abstract: A method for producing alkyl tertiary alkyl ether involves supplying a feed including isoolefins, alcohols, and dialkyl sulfides into a feed zone of a reactor; contacting the feed with a catalyst material in the reaction zone; and catalytically reacting the isooolefins and alcohols under conditions which favor forming resultant ether and inhibiting reaction of dialkyl sulfides with the catalyst material.

Abstract: In the instant invention the effluent from the DIPE reactor is separated in a novel separation process that includes, in one embodiment, two extraction steps serially combined to initially separate IPA from the reaction products by extraction with water. The aqueous IPA extract is separated in a second extraction step carried out using the C.sub.3 hydrocarbon feedstream to the process as extractor. To effectuate the separation of aqueous IPA, the second extraction is carried out at a temperature higher than that of the first extraction step. The organic phase from the first extraction containing DIPE, C.sub.3 hydrocarbons and water is separated in a splitter to provide dry DIPE as product. In another embodiment dry DIPE is produced by an initial aqueous extraction of the reaction effluent followed by distillation to separate C.sub.3 hydrocarbons and water overhead and DIPE as a bottom stream.

Abstract: A process is disclosed for integrating etherification to produce diisopropyl ether (DIPE) with processes to convert oxygenates and hydrocarbons to gasoline boiling range hydrocarbons in a manner which eliminates the requirement to recycle unreacted C.sub.3 hydrocarbons to the DIPE etherification zone. In the novel integrated process the unreacted C.sub.3 hydrocarbons are separated as vapor and passed to a conversion zone in contact with acidic metallosilicate catalyst. Depending on the conversion conditions the unreacted C.sub.3 hydrocarbons are converted to gasoline, distillate and/or aromatics, preferably in conjunction with additional feedstock containing lower oxygenates, olefins or paraffins. Also, isopropanol (IPA) and minor by-product dimers and trimers of propene from the DIPE reaction are separated and passed as a feedstream to the oxygenates and hydrocarbon conversion zone.

Abstract: Ethyl ester cannot be completely separated from methylene chloride by conventional distillation or rectification because of the maximum boiling azeotrope. Ethyl ether can be readily separated from methylene chloride by extractive distillation. Typical effective agents are t-butyl alcohol, n-propyl acetate or propoxypropanol.

Abstract: A process is disclosed for selectively sorbing contaminating amounts of isopropyl alcohol from diisopropyl ether by contacting with a high surface area strong acid type cation exchange resin in the hydrogen form, preferably having a mean pore diameter in the range from about 40 to about 259 Angstroms.

Abstract: Alcohol feedstock containing water is extracted with olefinic liquid and reacted catalytically to produce tertiary ether. Unreacted alcohol and olefin vapor separated from etherification effluent is converted along with aqueous alcoholic raffinate in a zeolite catalysis step to produce gasoline and paraffinic intermediate. By dehydrogating the C.sub.3 -C.sub.5 paraffins, an olefinic liquid rich in isoalkenes is obtained for recycle to the extractor as solvent for alcohol feedstock.

Abstract: Purified L-quebrachitol is recovered in increased quantities from rubber latex by dissolving concentrated solutions or pulverized solids of the serums in methyl alcohol under specified extraction conditions.

Abstract: A process for the production of pure dimethylether by feeding the dehydration product from a dimethylether-synthesis reactor into a distillation column for the production of pure dimethylether at defined trays of this column and withdrawal of pure dimethylether and a fraction containing contaminations at defined trays of the same column, whereby in addition washing liquids and bases can be added.

Abstract: A process for preparing an alkyl-tert-alkyl ether wherein an olefin having a double bond on a tertiary carbon atom and a primary alcohol are reacted in the presence of a catalyst under conditions sufficient to produce an azeotropic alcohol/ether/hydrocarbon mixture containing the alkyl-tert-alkyl ether. The azeotropic alcohol/ether/hydrocarbon mixture is subjected to a cyclic liquid phase adsorption process sequence to selectively remove the alcohol. The resulting non-azeotropic ether/hydrocarbon stream can then be easily separated by distillation to provide the desired alkyl-tert-alkyl ether product and a hydrocarbon product. The cyclic adsorption process employed to separate the alcohol from the ether/hydrocarbon mixture comprises introducing the alcohol/ether/hydrocarbon mixture into a plurality of adsorption colums containing an alcohol selective adsorbent, wherein each respective absorption column undergoes successive steps of adsorption and desorption.

Abstract: The invention concerns a process and apparatus for manufacturing methyl tert-butyl ether (MTBE) by reacting methanol with an isobutene-containing hydrocarbon mixture.This process is characterized by the steps of:introducing the reactants into a reaction-distillation zone containing at least two superposed and non-contiguous fixed beds (2a, 2b) of catalyst of the sulfonated resin type, wherein passageways are provided for a vapor phase, at least one distillation tray (4a), at least one liquid redistribution tray (5),maintaining distillation conditions in the zone so as to have a descending liquid phase and an ascending vapor phase,maintaining a continuous liquid phase in the lower part of the beds,discharging a vapor phase containing a high proportion of unconverted hydrocarbons from the top (8) of the zone, andwithdrawing a liquid phase of high MTBE content from the bottom (10) of the zone.

Abstract: An integrated process for the production of ether-rich liquid fuels containing MTBE and TAME by etherifying a hydrocarbon feedstock containing C.sub.4 + isoalkenes in the presence of a high stoichiometric excess of lower alkyl alcohol. Unreacted alcohol and olefins are passed to a zeolite catalyzed conversion reactor under olefinic and oxygenates conversion condition whereby gasoline and light hydrocarbons are produced. The light hydrocarbon fraction comprising C.sub.4 -C.sub.5 paraffins is dehydrogenated and C.sub.4 -C.sub.5 olefins are recycled to the etherification reactor.

Abstract: The invention relates to a process and apparatus for manufacturing methyl tert-butyl ether (MTBE) by reacting methanol with isobutene-containing hydrocarbons in a reaction zone having alternate beds of sulfonated resin catalyst and catalyst-free distillation zones wherein the zones also contain liquid redistribution plates.

Abstract: The invention relates to a gentle process for the separation of enol ethers from mixtures containing water-soluble alcohols by extraction, wherein an aqueous solution of a base is used as the extraction agent in a phase ratio of the amounts of the aqueous phase: enol ether/alcohol mixture of at least 0.5:1 and the extraction is carried out in several stages or continuously with a theoretical number of stages of at least two. The process is particularly suitable for separating off enol ethers which readily decompose during distillation.

Abstract: The invention relates to a process for the stabilization and purification of perfluoropolyethers of the general formulae (I) or (II) ##STR1## in which R=--F or --C.sub.a F.sub.2a+1R'=--F or --C.sub.b F.sub.2b+1n,m=0,1, . . . or 12, n being identical with or different from m, 1.ltoreq.n+m.ltoreq.15a,b=1,2, . . . or 10, a being identical with or different from b ##STR2## in which R"=--C.sub.f F.sub.2f+1R"'=--C.sub.g F.sub.2g+1X=--F or --CF.sub.3c,d,e=integers such that the molecular weight of the perfluoropolyether is between 200 and 2000, where c, d and e may be identical or different and the units [C.sub.3 F.sub.6 O].sub.c, [C.sub.2 F.sub.4 O].sub.d, and [CFXO].sub.e may be randomly distributed along the molecular chain of the perfluoropolyether,or of mixtures of perfluoropolyethers of this type. The process comprises heating the perfluoropolyethers or mixtures thereof to 150.degree.-360.degree. C.

Abstract: Gasoline octane number and yield are improved while excess fuel gas production is decreased in a catalytic cracking process by integrating etherification and oxygenate/aliphatic upgrading processes into the catalytic cracking unit product fractionation section.

Abstract: A process for preparation of polyglycerol is provided, comprising the steps of (a) reacting glycerol or diglycerol with hydrogen chloride at between about 340.degree. K. and about 410.degree. K. to yield a mixture that comprises an .alpha.-monochlorohydrin of glycerol or an .alpha.-monochlorohydrin of diglycerol, (b) mixing the .alpha.-monochlorohydrins and an alkali metal glycerolate or an alkali metal diglycerolate at a temperature of between about 320.degree. K. and 410.degree. K. to yield a mixture of alkali metal chloride and glycerol and/or diglycerol and polyglyerol, (c) separating the alkali metal chloride from the glycerols and (d) separating the polyglycerol from glycerol and/or diglycerol.

Abstract: An energy saving process for purification of methyl tertbutyl ether by fractional distillation of a mixture containing dissolved water and C.sub.4 hydrocarbons characterized by phase separation of water and methyl tertiary butyl ether within the distillation column and withdrawal of the separated water phase from the column at a point below the point at which the mixture is supplied to the column.

Abstract: A process is disclosed for converting a light hydrocarbon feedstock that contains a mixture of linear and branched olefins to ether-rich high octane gasoline streams that include tertiary alkyl and isoalkyl ethers such as MTBE, TAME, methyl isopropyl ether (MIPE), and methyl sec-butylether (MSBE). Further, it has been discovered that, following etherification unreacted paraffins in the process can be dehydrogenated to produce C.sub.3 -C.sub.4 olefins which can be recycled to the etherification process. The conversion is achieved by utilizing the differing reactivity of tertiary olefins under selected conditions compared to linear olefins in the catalyzed etherification processes. The process integrates a first stage tertiary olefin etherification, separation of ether-rich gasoline and a second stage linear olefin etherification to produce a second ether rich gasoline stream.

Abstract: A combined process for the dehydrogenation of C.sub.4 -C.sub.5 paraffins in a first zone and the etherification of olefins in a second zone improves efficiency by directly charging all but the lightest components of the dehydrogenation zone effluent to the etherification zone. This process is particularly suited for the production of gasoline boiling range ethers where an isoparaffin is dehydrogenated in a first zone to produce isoolefins. After separation of hydrogen and methane, the dehydrogenation zone effluent is charged along with methanol to an etherification zone for the production of MTBE. The etherification zone effluent is separated into at least three component streams comprising light ends, isoparaffins, and the ether product. Isoparaffins, separated from the etherification zone effluent, are recycled and combined with the feed to dehydrogenation zone.

Abstract: Olefin undergoes conversion in the presence of water to a mixture of alcohol and ether which is then subjected to various downstream operations including distillation and decantation to provide an ether-rich product containing little if any water. If desired the ether can be combined in any predetermined ratio with co-produced alcohol to provide alcohol/ether mixtures of desired composition. The foregoing process is especially suitable to the conversion of propylene and propylene-containing streams to diisopropyl ether and mixtures of isopropyl alcohol and diisopropyl ether which are useful, inter alia, as octane improves for gasoline.

Abstract: An integrated process for the production of alkylate and etherate rich high octane gasoline streams comprising the etherification to produce MTBE and TAME in the presence of a high stoichiometric excess of methanol followed by the conversion of unreacted methanol in contact with zeolite-type catalyst in the presence of aromatics to produce alkylated aromatics in gasoline. The light paraffinic effluent from the methanol conversion zone is reacted in contact with zeolite catalyst under aromatization conditions to produce an aromatics feedstream for the methanol conversion reaction. A supplemental olefinic feedstream is provided to the methanol conversion zone after optionally serving as stripping medium for the separation of methanol and etherate-rich C.sub.5 + gasoline from the etherification reaction.

Abstract: An improved process for reacting crude aqueous methanol feedstock with iso-olefinic hydrocarbons to produce C.sub.5.sup.+ methyl tertiary-alkly ethers, which comprises: contacting the aqueous methanol feedstock with a liquid hydrocarbon extractant rich in C.sub.4.sup.+ iso-alkene under liquid extraction conditons; recovering an organic extract phase comprising the hydrocarbon extractant and a major amount of methanol introduced in the feedstock; reacting the extracted methanol and C.sub.4.sup.+ isoalkene in contact with an acid etherification catalyst under catalytic reaction conditions to produce ether product; recovering an aqueous methanol raffinate phase containing the major amount of water introduced with the feedstock and a minor amount of feedstock methanol; and converting methanol from the aqueous raffinate phase to produce hydrocarbons.

Abstract: An integrated once through process for the production of ether-rich liquid fuels containing MTBE and TAME by etherifying a hydrocarbon feedstock containing C.sub.4 + isoalkenes in the presence of a high stoichiometric excess of lower alkyl alcohol. Unreacted alcohol and olefins are passes to a zeolite catalyzed conversion reactor under olefinic and oxygenates conversion condition whereby gasoline and light hydrocarbons are produced.

Abstract: An improved process for reacting crude aqueous methanol feedstock with tertiary-olefinic hydrocarbons to produce C.sub.5.sup.+ methyl tertiary-alkyl ethers, which comprises: contacting the aqueous methanol feedstock with a liquid hydrocarbon extractant rich in C.sub.4.sup.+ isoalkylene under liquid extraction conditions; recovering an organic extract phase comprising the hydrocarbon extractant and a major amount of methanol introduced in the feedstock; reacting the extracted methanol and C.sub.4.sup.+ isoalkene in contact with an acid etherification catalyst under catalytic reaction conditions to produce ether product; separating ether product from unreacted methanol and olefin; recovering an aqueous methanol raffinate phase containing the major amount of water introduced with the feedstock and a minor amount of feedstock methanol; and converting methanol from the aqueous raffinate phase concurrently with unreacted methanol and olefin from etherification effluent separation to produce hydrocarbons.

Abstract: Low concentrations of methanol and dimethyl ether in distillation column C.sub.4 -C.sub.5 raffinate produced in the formation of methyl tert.-alkyl ethers by the reaction of methanol with isoalkylenes are effectively removed from the residual C.sub.4 -C.sub.5 hydrocarbons by adsorption on a dual or compound adsorption bed containing silica gel as the methanol adsorbent and zeolite 13X as the dimethyl ether adsorbent.

Abstract: For the preparation of an ether, e.g., tertiary amyl methyl ether, an olefin-containing feed stream is catalytically etherified with an alcohol, e.g., methyl alcohol. The etherification product is fractionally distilled into an overhead fraction containing essentially unreacted, light hydrocarbons and unreacted alcohol and into a bottoms fraction containing essentially the desired ether. The overhead fraction is condensed and cooled to resultant immiscible phases, of which one contains essentially the alcohol and the other contains essentially the hydrocarbons, are removed separately from each other. Water may be added to the overhead stream to facilitate the formation of the two liquid phases.

Abstract: The instant invention relates to a process for the purification of dimethylether, which contains impurities, by feeding a mixture which contains the dimethylether at specific trays to a distillation column and withdrawal of the dimethylether and of impurities at specific trays of the same column.

Abstract: The present invention is an improved process for separating alcohols from ethers and/or hydrocarbon raffinate in an etherification process. The excess alcohol reactant, which forms azeotrope mixtures with the product ethers and C.sub.4 -C.sub.7 raffinate, is removed by passing the liquid azeotrope mixture over a pervaporation membrane which effectively breaks the azeotrope and permeates the alcohol with high flux and high selectivity. In a typical etherification process, one or more pervaporation membrane units can be located ahead of the ether/raffinate distillation step, in conjunction with the distillation step with a liquid side draw, after the distillation step, or a combination of any of the above. The present invention also provides an improved process for separating alcohols from ethers and/or hydrocarbon raffinate in an ether decomposition process for the production of high purity iso-alkene products.

Abstract: An adsorbent is used to recover methanol in unreacted C.sub.4 's from the MTBE process. Methanol is desorbed from the mixture in a closed loop regeneration system utilizing a circulating vapor at an elevated temperature. Gas from the adsorber is cooled to condense methanol which may be recycled to the MTBE reaction. Unreacted C.sub.4 's substantially free from methanol may be used in HF or sulfuric acid alkylation.

Abstract: This process for hydrogenating an olefin contained in a mixture of said olefin with an ether and optionally with sulfur, comprises reacting hydrogen with said mixture in the presence of a noble metal-containing catalyst, said catalyst containing at least one first noble metal from the palladium, rhodium, iridium and platinum group and at least one second other metal from the gold and platinum group.

Abstract: A process of removing methanol from a mixed stream comprising methanol and at least one hydrocarbon and utilizing the hydrocarbon as feed for an acid catalyzed alkylation unit which produces a spent acid stream is provided. The process is comprised of the steps of contacting the mixed stream with at least a portion of the alkylation unit spent acid stream whereby the methanol is reacted therewith and an aqueous reaction mixture is formed, separating the aqueous reaction mixture from the hydrocarbon and conducting the hydrocarbon to the alkylation unit.

Abstract: In the process for preparing methyl tert.-alkyl ether comprising the steps of (a) contacting and reacting in the liquid phase a reaction mixture formed by combining a stream consisting essentially of C.sub.4 -C.sub.5 hydrocarbons and containing at least some proportion of isoalkylene and a stoichiometric excess of methanol, with respect to the isoalkylene, to form a reaction product comprising methyl tert.-alkyl ether, unreacted methanol and unreacted C.sub.4 -C.sub.5 hydrocarbons; (b) isolating the methyl tert.-alkyl ether from the reaction product; and (c) recovering the unreacted methanol from the residual portion of the reaction product; the improvement which comprises selectively adsorbing the methanol constituent of said residual reaction product in a bed of crystalline molecular sieve adsorbent and recovering same by desorption using as a purge-desorption stream, the C.sub.4 -C.sub.5 hydrocarbon stream used to prepare the initial reaction mixture.

Abstract: A process for the production of methyl tertiary butyl ether comprising dimerizing ethylene to form a first butene-containing material; isomerizing the first butene-containing material to produce a second butene-containing material including an increased amount of isobutene relative to the first butene-containing material; and contacting at least a portion of the second butene-containing material with methanol at etherification conditions to produce an affluent enriched in methyl, tertiary butyl ether.

Abstract: In a process for separating C.sup.4 to C.sup.7 tertiary mono-olefins(s) present in a C.sup.4 to C.sup.7 hydrocarbon mixture containing diolefins which comprises selectively reacting said tertiary mono-olefin mixture with a primary alcohol in the presence of an acid catalyst to convert it to tertiary ether(s), separating the tertiary ether(s) from the unreacted hydrocarbon mixture and containing said tertiary ether(s) in the presence of a catalyst to decompose it to tertiary olefin(s) and a primary alcohol, the improvement which comprises hydrogenating the tertiary ether(s) after it has been separated from the unreacted hydrocarbon mixture and prior to decomposition to saturate the unsaturated ether(s) formed from the diolefins present in the hydrocarbon mixture.

Abstract: Preparation and recovery of 1-t-butoxy-2-propanol in a high state of purity from a crude etherification reaction product obtained by reaction of isobutylene with propylene glycol in the presence of a solid resin etherification catalyst is disclosed. The crude reaction product is distilled to obtain a 1-t-butoxy-2-propanol-containing distillate, thereby leaving propylene glycol as bottoms; the condensed distillate is then further distilled to separate 1-t-butoxy-2-propanol as an overhead product from higher boiling materials.

Abstract: Isopropyl ether cannot be completely removed from isopropyl ether--isopropanol--water mixtures by distillation because of the presence of the minimum ternary azeotrope. Isopropyl ether can be readily removed from mixtures containing it, isopropanol and water by using extractive distillation in which the extractive distillation agent is a higher boiling glycol, glycol ether or a mixture of them. Typical examples of effective agents are ethylene glycol, propylene glycol, diethylene glycol diethyl ether plus propylene glycol ethyl ether.

Abstract: The invention concerns a process for upgrading olefinic gasolines containing C.sub.5 hydrocarbons, but free of C.sub.4 hydrocarbons, by etherification. It is characterized in that the tertiary olefins of the charge are reacted (1 and 2) with methanol; the reaction effluent being then extracted (3) with water, in order to separate an aqueous phase containing the major part of the unreacted methanol from a hydrocarbon phase containing the major part of the formed ethers. The aqueous phase is then introduced in a distillation zone (4) where water is separated from methanol and recycled to the extraction zone (3), whereas methanol is recycled to the etherification zone (1 and 2).

Abstract: A process for producing methyl tertiary butyl ether is disclosed, comprising reacting isobutylene and methanol using a hydrocarbon mixture of 4 carbon atoms containing isobutylene and methanol as starting materials in a reaction zone containing an acidic ion exchange resin and distilling the resulting reaction mixture in a distillation column connected to the reaction zone to separate methyl tertiary butyl ether from the unreacted hydrocarbon mixture of 4 carbon atoms, wherein a mixture of the hydrocarbon mixture of 4 carbon atoms as a distillate from a top of the distillation column and methanol as a distillate by azeotropy is contacted with water in a second extraction step to wash and extract methanol with water, and the water containing the extracted methanol is then contacted with said hdyrocarbon mixture of 4 carbon atoms containing isobutylene which is fed to the reaction zone in a first extraction step in an upstream of the reaction zone to thereby transfer a part or a large portion of the methanol in

Abstract: Methyl t-butyl ether cannot be separated from close boiling hydrocarbons by distillation because of the proximity of their boiling points. Methyl t-butyl ether can be readily separated from close boiling hydrocarbons by using extractive distillation in which the extractive agent is higher boiling oxygenated, nitrogenous and/or sulfur containing organic compound or a mixture of two or more of these. Typical examples of effective agents are dimethylsulfoxide; dimethylsulfoxide and 2-octanone; dimethylsulfoxide, dimethylformamide and N-methyl pyrrolidone.

Abstract: A process for separating dimethyl ether from a hydrocarbon mixture which comprises contacting the hydrocarbon mixture with an aqueous solution containing a polar oxygenated hydrocarbon having a polarity of about 1.4 to about 2.0 Debyes.

Abstract: An improved method is disclosed for regenerating adsorbents used in an integrated process for the production of ethers such as methyl tertiary butyl ether by the reaction of an alcohol with an isoolefin. The sorbents are used to remove such compounds as the product ether and the feed alcohol from a hydrocarbon-rich stream withdrawn from the etherification zone. The regeneration procedure includes contacting the sorbent with a heated portion of the treated hydrocarbon stream. The resultant contaminated hydrocarbon stream is passed into a stripping column used to remove light ends from the effluent of a dehydrogenation zone in which the isoolefin fed to the etherification zone is produced. The hydrocarbonaceous compounds collected on the sorbent are thus recycled rather than being destroyed or lost in low purity effluent streams.

Abstract: An improved method is disclosed for regenerating adsorbents used in an integrated process for the production of ethers such as methyl tertiary butyl ether by the reaction of an alcohol with an isoolefin. The sorbents are used to remove oxygenated compounds such as the product ether and the feed alcohol from a hydrocarbon-rich stream withdrawn from the etherification zone. The regeneration procedure includes contacting the sorbent with a heated hydrocarbon stream. The resultant contaminated hydrocarbon stream is passed into a stripping column used to remove light ends from the effluent of a dehydrogenation zone in which the isoolefin fed to the etherification zone is produced. The oxygenated compounds collected on the sorbent are thus selectively recycled or rejected rather than being destroyed or lost in low purity effluent streams.

Abstract: Isopropyl ether cannot be completely removed from isopropyl ether-isopropanol-water mixtures by distillation because of the presence of the minimum ternary azeotrope. Isopropyl ether can be readily removed from mixtures containing it, isopropanol and water by using extractive distillation in which the extractive distillation agent is dimethylsulfoxide with or without a mixture of higher boiling oxygenated and/or nitrogenous organic compounds. Typical examples are dimethylsulfoxide; dimethylsulfoxide and ethylene glycol; dimethylsulfoxide, dimethylformamide and 1,4-butanediol.

Abstract: Isopropyl ether cannot be completely removed from isopropyl ether-acetone mixtures by distillation because of the presence of the minimum binary azeotrope. Isopropyl ether can be readily removed from mixtures containing it and acetone by using extractive distillation in which the extractive distillation agent is a higher boiling oxygenated, nitrogenous and/or sulfur containing compound or a mixture of these. Typical examples of effective agents are: dimethylsulfoxide; sulfolane and propylene glycol; adiponitrile, glycerine and ethylene glycol.

Abstract: The reaction product from etherification of C.sub.4 -C.sub.7 isoolefins with methanol in the presence of an acidic catalyst is washed with water in the presence of inert hydrocarbons thereby removing methanol and a part of the tertiary alcohol. The aqueous extract solution bottoms is distilled to separate methanol as overhead. Tertiary alcohols are withdrawn as a side stream from a tray of the distillation column with a high concentration thereof and fed into the washing column.

Abstract: Isopropyl ether cannot be completely removed from isopropyl ether - methyl ethyl ketone mixtures by distillation because of the presence of the minimum binary azeotrope. Isopropyl ether can be readily removed from mixtures containing it and methyl ethyl ketone by using extractive distillation in which the extractive distillation agent is a higher boiling oxygenated and/or nitrogenous organic compound or a mixture of these. Typical examples of effective agents are adiponitrile; ehtylene carbonate plus dimethylformamide; adiponitrile plus dimethylformamide plus glycerine.

Abstract: Isopropyl ether cannot be completely removed from isopropyl ether-isopropanol-water mixtures by distillation because of the presence of the minimum ternary azeotrope. Isopropyl ether can be readily removed from mixtures containing it, isopropanol and water by using extractive distillation in which the extractive distillation agent is a higher boiling oxygenated, nitrogenous and/or sulfur containing organic compound or a mixture of these. Typical examples of effective agents are ethylene glycol; dimethylsulfoxide plus propylene glycol; dimethylsulfoxide plus dimethylformamide plus diethylene glycol diethyl ether.

Abstract: A process for the preparation of pure alkyl tertiary alkyl ethers and hydrocarbon raffinates which are substantially free from tertiary olefins and alkanols. An alkanol and a hydrocarbon mixture containing at least one tertiary olefin are contacted with the alkanol being present in a stoichiometric excess. The reaction product is removed from the reaction zone and excess alkanol in the reaction product or a partial stream thereof is absorbed on a synthetic ion exchanger containing groups which exchange cations or anions or mixtures of such ion exchangers. After absorption of at least a portion of the alkanol on the synthetic ion exchanger, the alkanol is desorbed by contacting the same with a hydrocarbon mixture containing at least one tertiary olefin.