Abstract: Acetaldehyde may be effectively removed from a contaminated methanol stream using a distillation method wherein a solvent stream containing a relatively heavy polar compound such as water or propylene glycol is utilized as an extractive distillation solvent. Following the separation of the polar compound from the bottoms stream obtained by extractive distillation, the purified methanol may be recycled for use as a reaction solvent in an olefin epoxidation process.

Abstract: A solution of an organic compound containing at least a polymer is treated by adding an amount of water to said solution, distilling the organic compound to recover the organic compound, and incinerating the remained aqueous solution containing the polymer.

Abstract: A process for the preparation and fractionation of a mixture of dimethyl ether and chloromethane by extractive distillation with water as extractant. The mixture is prepared by reacting methanol with hydrogen chloride. It is then subjected to an extractive distillation with water as extractant, resulting in chloromethane as top product. In the next step, the dimethyl ether is removed by distillation and, in another step, the extraction water is separated from the methanol which is still present.

Abstract: A method for recovering methanol from sulfur-based wood pulping process vapors, which contain at least methanol and dimethyl disulfide. The method involves three steps. The first step consists of introducing the vapors into a first distillation tower at a vapor introduction point. The second step consists of introducing water into the first tower at a point above the vapor introduction point. The third step consists of heating liquid which is in the first tower below the vapor introduction point so that a liquid stream flows from the bottom of the first tower and a gas stream flows from the top of the first tower. The liquid stream contains most of the methanol originally in the vapors. The gas stream contains most of the dimethyl disulfide originally in the vapors. The liquid stream can then be distilled in a second distillation tower by conventional distillation to produce dry methanol. The first and third steps can be combined by introducing sufficiently heated vapors.

Abstract: In the manufacture of MTBE from TBA and methanol, acidic by-products formed during the etherification reaction are removed by fractionating the etherification reaction product in a first MTBE distillation column to provide a first lower boiling distillation fraction comprising isobutylene, MTBE, methanol and acidic by-products and a first higher boiling distillation fraction comprising methanol, TBA and water, fractionating the first higher boiling distillation fraction in a recycle distillation column to provide a lower boiling TBA recycle fraction and a higher boiling water fraction, recycling the higher boiling water fraction to the MTBE distillation column at a charge point above the charge point for the etherification reaction product, and adding aqueous sodium hydroxide to the recycled higher boiling water fraction in an amount sufficient to neutralize the acidic by-products charged to the MTBE distillation column.

Abstract: A method of removing dimethyl terephthalate (DMT) from a vapor stream. The vapor stream includes dimethyl terephthalate (DMT), methylhydroxyethyl terephthalate (MHET), glycols and methanol. A distillation column is held under an elevated pressure of 100 to 500 kPag and at a temperature of at least 85.degree. C. It has (i) a plurality of distillation trays; (ii) methanol liquid sprays between the trays; (iii) a main spray zone below the trays and (iv) a liquid pool of methanol in the bottom of the column. The vapor stream is directed into the distillation column, above the liquid pool and below the main spray zone, thereby forming a stream of liquid and vapor. The stream of liquid is directed away from the distillation column walls and into the liquid pool at the bottom of the column.

Abstract: From a mixture containing methanol, ethanol, n-propanol, isobutanol water and other high-boiling and low-boiling compounds, the claimed process enables three separate streams to be obtained, one an anhydrous stream of methanol or methanol and ethanol (I), one containing most of the n-propanol present in the feed mixture (II), and one containing most of the isobutanol present in the feed mixture (III), by using three fractionating columns.

Abstract: A distillation process is used to separate methanol from a mixture of methanol with methyl acrylate or methyl methacrylate, as well as from a mixture of methanol and water with methyl acrylate or methyl methacrylate with the use of an azeotropic solvent, which forms an azeotropic mixture with methanol. In distilling such a mixture by the use of a distillation column:(1) part of the condensate of vapors distilled over from the top of the distillation column top is returned to the top of the column;(2) the remaining condensate is separated into two layers;(3) the upper layer essentially composed of an azeotropic solvent from the two separated layers is fed to an intermediate portion of the distillation column;(4) the lower layer essentially composed of methanol from the above two separated layers is withdrawn from the distillation system; and(5) methyl acrylate or methyl methacrylate, or else, methyl acrylate or methyl methacrylate and water, are recovered from the bottom of the column.

Abstract: A methanol refining column and method using an intermediate reboiler. Use of the intermediate reboiler reduces methanol production energy requirements. A side stream at or near a fusel oil takeoff point is heated in an intermediate reboiler by a low temperature heating medium (relative to a bottoms reboiler) and returned to the column at or near the fusel oil take-off tray. The take-off tray is operated at 85.degree.-110.degree. C., and 70-90 percent of the reboiler duty is supplied through the intermediate reboiler. The remaining heat load is supplied by a bottoms steam reboiler.

Abstract: A method of continuously distilling off the components of a mixture containing phenols, water and methanol using a single distillation column, wherein methanol is recovered from the top of the column, water containing phenols is dragged as a side stream from a recovery section of the column, and phenols are recovered as a bottom product. The method permits efficient separation by the single distillation column of the three components with high purity and low utility energy.

Abstract: A method for recovering hydrobromic acid and methanol from a filtrate obtained by brominating bisphenol A in a methanol solvent and filtering off the resulting brominated bisphenol A, which comprises adding water to the filtrate, followed by distillation for purification.

Abstract: A method of inhibiting fouling in distillation towers, overhead lines, reflux lines, and condensers operating in a process to manufacture and purify epichlorohydrin. This method resides in treating process streams entering or exiting such towers, lines and condensers, including feed streams, reflux streams, gaseous or liquid overhead streams, with an effective antifouling amount of a C.sub.3 -C.sub.9 linear or branched alkyl substituted catechol, or mixtures thereof.

Abstract: A process is disclosed for the dehydration of a mixture of methanol and higher alcohols, containing 20 to 80% by weight of methanol, 1 to 60% by weight of at least a higher alcohol selected from those containing from 2 to 10 carbon atoms, 1 to 50% by weight of water and 0.

Abstract: A process is described for recovering polyester-grade ethylene glycol from crude ethylene glycol containing at least one component which has a normal boiling point below that of ethylene glycol, and which can form a UV absorber in the presence of ethylene glycol which comprises supplying to an ethylene glycol distillation system, preferably comprising a fractional distillation zone having an upper portion, a lower portion and an intermediate portion a crude ethylene glycol stream at a determined pH of less than about 7.

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 process for the acid-catalyzed reaction of acetone with methanol to form 2,2-dimethoxypropane may be significantly improved if a stoichiometric ratio of methanol/acetone is employed in the initial reaction.Of particular advantage is the use of stoichiometric amounts of reactants in order to (1) avoid the expense of using an excess of either reactant, and (2) facilitate the removal of the 2,2-dimethoxypropane as an azeotrope with the methanol, thereby avoiding costly and complex product recovery methods.

Abstract: A process for purifying methanol which comprises introducing crude synthetic methanol obtained by catalytic reaction of carbon oxide and hydrogen into a rectifying column either as such or after it is first introduced into a topping column and distilled with or without the addition of water to remove low-boiling components from the top of the topping column, and distilling it in the rectifying column to withdraw purified methanol from the top of the column and mainly water from the bottom of the column; wherein an auxiliary distillation column is provided side by side with the rectifying column, and the rectifying column and the auxiliary distillation column are operated under particular conditions.

Abstract: Distillative separation of liquid mixtures of one or more water-insoluble substances which have boiling points higher than that of water and one or more substances which have boiling points lower than that of water or which form azeotropes having boiling points lower than that of water, wherein the mixture to be distilled is mixed with a quantity of water such that the boiling point of the water under the pressure applied limits the bottom temperature of the mixture of substances to be separated.

Abstract: A process for converting crude aqueous methanol feedstock to liquid hydrocarbons in contact witha medium pore shape selective crystalline acid zeolite catalyst, such as HZSM-5. In a preferred embodiment, the novel technique comprises the steps of: (a) contacting a crude methanol feedstock containing a minor amount of water with a liquid hydrocarbon extraction stream under extraction conditions favorable to selective extraction of the methanol, thereby providing an extract liquid stream rich in methanol and an aqueous raffinate stream lean in methanol; (b) charging the extracted methanol substantially free of water to said reaction zone under process conditions to convert substantially all methanol to hydrocarbons; (c) cooling reaction effluent to recover aqueous liquid byproduct stream, gas rich in C.sub.2.sup.- hydrocarbons, liquid rich in C.sub.3 -C.sub.4 and C.sub.5.sup.

Abstract: For the distillation of a stream consisting essentially of alcohols of 6-20 carbon atoms, water and methanol, the methanol is first separated from the homogeneous, aqueous solution as the overhead product by distillation under a head pressure of 500-1,000 mbar. The bottoms discharge is mechanically separated under normal pressure and at a temperature of 5.degree.-95.degree. C. in a phase separator to obtain a discrete water phase preferably containing at least two thirds of the feedstream water. The remaining organic phase is then transferred from the phase separator into a second distillation column and the organic phase is dewatered in the latter at 100-500 mbar. The head product from the second column is conducted to a second phase separator; the aqueous phase is separated therein at a temperature of 5.degree.-95.degree. C. and optionally returned into the first phase separator. The bottom product from the second distillation column is passed into a downstream distillation stage wherein the C.sub.6 to C.

Abstract: The invention relates to a process for the production of grade AA methanol by distilling raw methanol in several distillation stages, for separating grade AA methanol, tail gas, and fusel oil from the raw methanol and further processing the fusel oil to produce additional methanol of grade AA quality at a return ratio of 5:1 or higher.

Abstract: A C.sub.1 -C.sub.4 alkanol and its corresponding acetate or a C.sub.1 -C.sub.2 alkanol and its corresponding propionate are separated by extractive distillation utilizing an aromatic hydrocarbon as the extractive solvent. Transesterification of lower alkanols and lower alkyl acetates or propionates is effected by means of extractive distillation and the preparation of an intermediate ester of a higher boiling alcohol.

Abstract: A process is provided wherein acetaldehyde and methanol are obtained from reaction mixtures which result from the homologization of methanol and which in addition to acetaldehyde essentially contain acetaldehyde dimethylacetal, methanol, methyl acetate and water.

Abstract: Butenes are added to the methanol-containing methyl-tertiary-butyl ether (MTBE) reactor effluent fractionation to effect recovery of substantially methanol-free MTBE bottoms product. Methanol analysis taken below the fractionator feed locus manipulates control of butenes addition. In an embodiment, the methanol-butenes-containing overhead stream from the fractionation is treated over activated alumina to adsorb methanol, yielding a methanol-free butenes feed for HF alkylation of isobutane. The used adsorbent can be regenerated using hot butenes product and/or MTBE reactor feed vapor with the recovered methanol being recycled to the MTBE reaction.

Abstract: In the hydrolysis of methyl acetate to acetic acid, the improvement comprising a flasher or stripper to separate methyl acetate and water from the hydrolyzer product stream and the recycle of these directly to the hydrolyzer.

Abstract: Purified methanol is produced by distilling a water methanol mixture in (a) a first column from which is taken a product methanol stream at an upper level, weakly aqueous methanol as a side stream and water as bottoms and (b) a second column in which that weakly aqueous methanol is separated into an overhead product stream and aqueous methanol bottoms. The first column may be preceded by a preliminary volatiles-removal column. The process is economical in heat consumption, especially when methanol vapor from the second column is heat-exchanged with the feed or bottoms of the first column.

Abstract: An azeotropic distillation is conducted by feeding a part of an entrainer to the lower region of an azeotropic zone in a distillation column.

Abstract: A methanol production process including synthesis gas generation, methanol synthesis and methanol distillation includes an autonomous system in which low pressure steam is raised by heat exchange with a fluid stream at 120.degree.-300.degree. C. in the process, the low pressure steam is used as live steam to heat at least distillation column in the distillation section and bottoms water from a distillation column in that section is used as feed to the autonomous steam system.