Abstract: A process for the distillative recovery of high purity monoethylene glycol from the hydrolysis product of ethylene oxide by pressure dewatering, vacuum dewatering and subsequent purifying distillation, which includes the pressure dewatering columns or at least the first pressure dewatering column of the battery (2, 3, 4) having a stripping section with at least one separating stage, preferably with from 2 to 10 separating stages, particularly preferably with from 3 to 6 stages, and a portion of the overhead stream of the pressure dewatering column(s) (2, 3, 4) having a stripping section being removed from the system.

Abstract: A method of recovering a decomposition product from a polyurethane, the method comprising the steps of thermally decomposing a polyurethane into a liquid containing a polyol and a urea compound which is soluble in the polyol, and solids containing a urea compound which is insoluble in the liquid in the presence of a polyamine compound at a temperature of 120 to 250° C.; removing the solids; hydrolyzing the residue with water retained at a high temperature of 200 to 320° C. and a high pressure; and recovering the resulting polyamine and/or polyol.

Abstract: The present invention provides a method of recovering a polyamine compound and/or a polyol compound useful for starting materials of polyurethane resin in an industrially advantageous manner by first dissolving the polyurethane resin such as polyurethane foams discharged in a large amount as industrial wastes in a solubilizing agent containing a polyamine compound, a low molecular glycol or an amino alcohol, hydrolyzing the resulting solution with liquid water at 200 to 320° C., then recovering the polyamino compound and/or polyol compound thus formed.

Abstract: The invention relates to a method comprising a multistep process for recovering betaine, erythritol, inositol, sucrose, mannitol, glycerol and amino acids from corresponding starting materials. The invention comprises the use of a weakly acid cation exchange resin in chromatographic column in the multistep process. The starting materials are especially beet molasses, betaine molasses, syrups, thick juices, raw juices, corn steep cane based solutions and glycerol.

Abstract: A method of recovering 1,3 -propanediol (PDO) from fermentation broth is disclosed. The method employs ion exclusion resins to separate PDO from other impurities. The product fraction contains greater than 80% pure PDO with high yield.

Abstract: A distillation procedure is provided for the separation of impurities from organic materials such as glycols and glycol ethers whereby a liquid stripping component is interfaced into a distillation column with or below the organic material introduction, heat being provided by a reboiler, the stripping component and impurities being removed overhead.

Abstract: A method of decomposing wastes containing target compounds having one or more of hydrolyzable bonds of ether bond, ester bond, amide bond and isocyanate bond wherein the method comprises continuously supplying the wastes in a molten state or liquid state to a reactor, continuously supplying super-critical water or high pressure/high temperature water to the reactor, bringing the water into contact with the wastes, thereby decomposing the target compounds and then recovering them as raw material compounds or derivatives thereof for the target compounds. Target compounds contained in wastes in chemical plants which could not be utilized but merely incinerated or discarded so far are continuously decomposed into raw material compounds or derivatives thereof for the aimed compound and can be reutilized effectively.

Abstract: A process for preparing high-purity phytantriol, that includes rectifying the phytantriol which is obtained and is contaminated with lower and/or higher boiling byproducts under medium vacuum in rectification columns containing metal cloth packings with ordered structure using channel liquid distributors with a minimum of 500 drip points/m2, which are arranged at an angle of 90° to the cloth layers of the packing elements located directly below the distributors, in which 2 or more of the packing elements underneath the liquid distributors have only a small height, which ensure absolute exclusion of air and a strictly adiabatic procedure. The preparation of high-purity phytantriol takes place particularly advantageously when the phytantriol which is contaminated with byproducts is a phytantriol which has been obtained by reacting isophytol with performic acid and subsequently hydrolyzing the product formed in the reaction with alkaline agents in a manner known per se.

Abstract: The invention relates to a process for preparing trimethylolpropane with simultaneous formation of formate salts of the formula M(OOCH)n  (I), where M represents the alkali metals lithium, sodium, potassium, rubidium, caesium and/or the alkaline earth metals beryllium, calcium, strontium, barium and n is 1 when M is an alkali metal and is 2 when M is an alkaline earth metal, where n-butyraldehyde, formaldehyde and a base are reacted by the inorganic Cannizzaro process and the reaction mixture formed is subjected to vapour pressure filtration as a suspension, if appropriate after partly removing distillable constituents, such as water.

Abstract: A method for the production of monoethylene glycol of high purity is disclosed which comprises subjecting ethylene to catalytic vapor phase oxidation with a molecular oxygen-containing gas thereby obtaining an ethylene oxide-containing gas, exposing the ethylene oxide-containing gas to an absorbing solution and stripping the resultant ethylene oxide-containing solution in a stripper, condensing the vapor emanating from the top of the stripper thereby obtaining crude ethylene oxide, subjecting at least part of the crude ethylene oxide to a hydration reaction, adding an alkaline substance to the hydration reaction solution in an amount of not less than 0.5 atomic equivalent weight relative to the chlorine atom contained in the hydration reaction solution or dehydrating the hydration reaction solution and introducing the side cut technique to the monoethylene glycol rectification column, and acquiring the monoethylene glycol from the side cut part.

Abstract: A method for the continuous crystallization of sugars or polyols, comprising the steps of: arranging in a thin, turbulent and dynamic layer a continuous flow of melted mass of a compound selected among the group comprising sugars and polyols, with at least 98% of dry material, and a mass of said compound in crystalline form as a crystallization seed; advancing said thin layer of material along a cooling wall at a temperature between −15° C. and +5° C.; granulating the material while said thin layer is advanced along the cooling wall, thus obtaining granules of the crystallized compound, and cooling said granules to room temperature, after a predetermined maturation time.

Abstract: A process for the separation by distillation of a mixture of 1,4-butanediol and at least one 4-hydroxybutyraldehyde, its cyclic hemiacetal and its cyclic full acetals with at least one further alcohol by carrying out the distillation in the presence of an alkaline compound. The mixture to be separated preferably contains a cyclic full acetal of 4-hydroxybutyraldehyde with a further alcohol which has a lower boiling point than butanediol and also the further alcohol in free form. The process is particularly suitable for the separation by distillation of mixtures formed in the hydrogenation of maleic acid derivatives.

Abstract: The present invention provides a method of recovering a polyamine compound and/or a polyol compound useful for starting materials of polyurethane resin in an industrially advantageous manner by first dissolving the polyurethane resin such as polyurethane foams discharged in a large amount as industrial wastes in a solubilizing agent containing a polyamine compound, a low molecular glycol or an amino alcohol, hydrolyzing the resulting solution with liquid water at 200 to 320° C., then recovering the polyamino compound and/or polyol compound thus formed.

Abstract: High purity 1,3-butylene glycol obtained from acetaldol by a liquid phase hydrogen reduction method, by adding a base to crude 1,3-butylene glycol free of high-boiling material, heat-treating the mixture and then distilling off 1,3-butylene glycol; and distilling off low-boiling materials from 1,3-butylene glycol. In high performance liquid chromatography analysis under specified conditions, each peak eluted in a relative retention time range of 4.0 to 5.5, taking a relative retention time of 1,3-butylene as 1.0, has an absorbance of 0.02 or less at a measuring wavelength of 210 nm. This has no odor and shows less change with time.

Abstract: The invention concerns a process for the isolation of polyols, such as 1,3-propanediol, from a fermentation broth. Specifically, the invention discloses a process of adding base to the fermentation broth to raise the pH to a suitable level for reduction of impurity formation during isolation of the polyol.

Abstract: Aldehyde compounds contained in polycyclic diols as impurities are effectively removed by distilling the polycyclic diols in the presence of an alkali metal compound and/or a alkaline earth compound. The distilled polycyclic diols are useful as a diol component of a polymer such as polycarbonate with less yellowing.

Abstract: In a process for isolating alkylene glycol having a low aldehyde content, in which a mixture comprising alkylene glycol is subjected to a final distillation, formic acid or a formate or a mixture of two or more formates or a mixture of formic acid and one or more formates is present in the mixture comprising alkylene glycol.

Abstract: Hexanediol is prepared by hydrogenating dialkyl adipates or mixtures which contain a dialkyl adipate as the essential component and organic halogen compounds as impurities, by a process in which, before the hydrogenation, the dialkyl adipates or the mixtures containing dialkyl adipates are passed at from 50 to 250° C. and from 1 to 100 bar over copper catalysts which have a copper content, calculated as CuO, of from 0.5 to 80% by weight, a surface area of from 5 to 1500 m2/g, a porosity of from 0.05 to 1.5 cm3/g and a copper surface area of from 0.1 to 20 m2/g, in order to remove the organic halogen compounds.

Abstract: A process for recovering glycols from used glycol-containing technical fluids, especially from used antifreeze comprises adding to the used glycol-containing technical fluids an organic solvent which forms with the glycol to be separated off an azeotropic mixture which has a lower boiling point than the glycol itself and distilling off this azeotropic mixture.

Abstract: A procedure is provided for the separation of close boiling impurities from products which have slightly higher polarity than the impurities, for example, separation of di-propylene glycol di-tert-butyl ether (DE) from di-propylene glycol mono-tert-butyl ether (DPTB) by distillation, water or steam being used as stripping component with heat provided by a reboiler.

Abstract: This invention relates to a process for preparing and isolating glycols and to a thin-film evaporator which is used in carrying out the process.

Abstract: A method of decomposing wastes containing target compounds having one or more of hydrolyzable bonds of ether bond, ester bond, amide bond and isocyanate bond wherein the method comprises continuously supplying the wastes in a molten state or liquid state to a reactor, continuously supplying super-critical water or high pressure/high temperature water to the reactor, bringing the water into contact with the wastes, thereby decomposing the target compounds and then recovering them as raw material compounds or derivatives thereof for the target compounds. Target compounds contained in wastes in chemical plants which could not be utilized but merely incinerated or discarded so far are continuously decomposed into raw material compounds or derivatives thereof for the aimed compound and can be reutilized effectively.

Abstract: High purity ethylene glycol containing 2000 ppm or less aldehyde is contacted with a solid strong acid cation exchange resin and an ethylene glycol product reduced in aldehydes content is recovered.

Abstract: D-mannitol having a specific surface area of not less than about 1 m2/g is disclosed. The D-mannitol shows improved compressibility and is useful as an excipient.

Abstract: Disclosed is a process for the removal of impurities, especially color forming impurities, from 1,3-propanediol.

Abstract: Reduction in the content of acetals or ketone acetals in a reaction mixture containing at least 10 moles alcohol per mole acetal or ketone acetal can be achieved hydrogenolytically when the reaction mixture is hydrogenated at 80° to 250° C. at a hydrogen partial pressure of 0.5 to 30 MPa in the presence of activated carbon charged with noble metal as catalyst.

Abstract: A multi-stage apparatus and a process for recycling used engine coolant employs a combination of filtration, dissolved air floatation, centrifugation (hydrocyclone separation), semi-permeable nano filtration, reverse osmosis, and continuous deionization for separating ethylene glycol, with or without propylene glycol, and water from used engine coolant. The engine coolant is pre-filtered through a series of filters. The filters remove particulate contaminates. This filtered fluid is then subjected to dissolved air floatation and/or centrifugation to remove organic petroleum contaminants. Then, it is pressurized prior to being passed through semi-permeable nano filtration. The nano filtration separates the feed stream into a ultra filtration solution and a concentrated waste solution. The concentrate solution is returned to a centrifuged coolant tank for continuous circulation through the nano filtration device.

Abstract: A process for producing an alkylene glycol, which is a continuous process for producing an alkylene glycol comprising the following steps (1) to (4), wherein the hydrolysis step (2) is divided into a plurality of stages, and the hydrolysis is carried out so that the water concentration in a reaction stage wherein the conversion of the alkylene carbonate is at least 60%, is from 15 to 30 wt %: (1) a carbonating step of reacting an alkylene oxide with carbon dioxide gas in the presence of a carbonating catalyst to form a reaction solution containing an alkylene carbonate, (2) a hydrolysis step of hydrolyzing the reaction solution obtained in step (1) while releasing carbon dioxide gas, to form an aqueous alkylene glycol solution, (3) a distillation step of distilling the aqueous alkylene glycol solution to obtain at least a dehydrated alkylene glycol and a solution containing the carbonating catalyst, and (4) a recycling step of supplying the solution containing the carbonating catalyst to the carbonating s

Abstract: The continuous process for making crystalline D-sorbitol using a melt crystallizer consisting of a cooled container and a horizontally arranged rotatable shaft equipped with disk elements and mixing parts to form a worm includes evaporating an aqueous D-sorbitol solution at 5 to 200 mbar and at a temperature of 130.degree. to 170.degree. C. in vacuum, advantageously in a thin film evaporator, to obtain a D-sorbitol melt containing less than 0.5 % by weight water; cooling the D-sorbitol melt to a temperature of 5 to 15.degree. C. above a solidification point of the D-sorbitol melt; melt crystallizing the D-sorbitol melt obtained during the evaporating in the melt crystallizer with an average dwell time of 1 to 5 hours to form D-sorbitol crystals and grinding and sieving the D-sorbitol crystals formed during the melt crystallizing of step d) to form a D-sorbitol end product containing more than 90% by weight of a .gamma. modification of crystalline D-sorbitol.

Abstract: The invention provides a process for the purification of a butane-1,4-diol feed containing a minor amount of the cyclic acetal, 2-(4'-hydroxybutoxy)-tetrahydrofuran, which comprises hydrogenating the butane-1,4-diol feed in a hydrogenation zone in the presence of a minor amount of water and a hydrogenation catalyst, and recovering from the hydrogenation zone a butane-1,4-diol product that has a reduced 2-(4'-hydroxybutoxy)-tetrahydrofuran content compared with the butane-1,4-diol feed.

Abstract: The invention relates to a process for evaporating a liquid containing vaporizable oxidation-sensitive compounds in an evaporator in which the liquid is brought into contact with a heated solid surface for evaporation, by a process in which direct contact between the resulting vapor phase and the heated solid surface is substantially avoided. It also directed to an evaporator composed of a heatable solid surface (16), an apparatus (2, 3) for heating the solid surface and an apparatus (10) for feeding a liquid containing vaporizable compounds to the heatable solid surface, wherein the apparatus for feeding the liquid is designed and arranged in the evaporator in such a way (12, 14, 18) that direct contact between a resulting vapor phase and the heatable solid surface is substantially avoided.

Abstract: A process for producing a high-purity erythritol crystal comprising a crystallization step of subjecting an erythritol-containing aqueous solution as a raw solution to crystallization, wherein an erythritol concentration of said erythritol-containing aqueous solution is adjusted to 30 to 60% by weight at the beginning of the crystallization step; said erythritol-containing aqueous solution is cooled at a cooling rate of not more than 20.degree. C./hour; a seed crystal of erythritol is added to said erythritol-containing aqueous solution in the course of the cooling, and the solution is cooled to not more than 20.degree. C. Such a process for producing a high-purity erythritol crystal of the present invention has a still higher purity and is further improved in crystal shape as compared to those produced by conventional processes.

Abstract: A process and a system is disclosed for recovering glycol from glycol and brine mixtures produced from oil or natural gas wells that combines energy efficiency with a capability for handling salt and other solids contained in the mixture. The system comprises three effect evaporator systems in series. Each effect evaporator system comprises an evaporator, a separator vessel, product pumps, and a solids removal system.The process utilizes the system to remove salt and other solids as well as excess water leaving a glycol stream that can be reused as a hydrate inhibitor. The process begins by preheating a glycol/brine stream comprising approximately fifty percent (50%) glycol. The stream is then subjected to three evaporation cycles. The first evaporation cycle comprises introducing the preheated stream into a suppressed boiling point evaporator where the stream is heated under a constant pressure. The stream pressure is then dropped to cause a portion of the water contained in the stream to vaporize or flash.

Abstract: This invention relates to a process for purifying crude 1,4-butanediol by melt crystallization and a process for preparing 1,4-butanediol by utilizing the purification process. 1,4-Butanediol is important as a material for synthesizing polyester resins, .gamma.-butyrolactone, tetrahydrofuran, etc.

Abstract: The invention comprises spray dried erythritol which may also be agglomerated. The product is a free-flowing powder which preferably has 60% or more of its particles in the range 10 to 250 microns. The product is useful as a sweetener for which it is particularly adapted to be combined with a synthetic sweetener such as aspartame. The product is also useful in combination with a binder, particularly a potato maltodextrin, as a tabletting composition. The invention also comprises a process for making the product.

Abstract: This invention relates to a process for the purification of polyether polyols. This process enables the removal of residual alkaline metal catalyst from produced polyether polyol. It comprises a) adding glycerine to a polyether polyol that contains Group IA alkaline metal catalyst to form a precipitate, and b) separating the precipitate formed in a) to provide a purified polyether polyol. The present invention also relates to the purified polyether polyol produced by this process, the precipitate produced by this process, and the use of the precipitate as an alkaline metal catalyst in a process for the production of polyether polyols.

Abstract: Contaminated glycol is refined by vacuum distillation. Specifically the evaporator is heated to a temperature below the degradation temperature of the glycol. The vacuum is used to bring the flashpoint down sufficiently so that glycol evaporates or flashes at that temperature. The glycol is condensed and filtered through activated granular carbon. The principal use of refining the glycol is to refine the triethylene glycol used in natural gas dehydration plants. For such purposes the equipment is mounted upon a trailer to be taken to the plant for cleaning glycol. In such instance, in addition to refining the glycol, a cleaning agent (which contains a degreaser) is added to the refined glycol. The glycol is refined while the natural gas dehydration plant is in normal operation and therefore it is not necessary to stop the natural gas dehydration plant for refining the glycol used therein.

Abstract: A process for activating double metal cyanide catalysts is disclosed. A polyol starter or starter/catalyst mixture is heated under vacuum under conditions effective to achieve improved stripping compared with that which can be achieved through conventional vacuum stripping. Coupling vacuum stripping with inert gas sparging or stripping in the presence of an organic solvent gives a starter/catalyst mixture that activates rapidly in an epoxide polymerization process. Rapid activation makes process start-ups reliable and reduces cycle time. The process gives polyols with lower viscosity, lower polydispersity, and lower unsaturation for better polyurethanes.

Abstract: An amount of water is added to a glycol solution to be purified to enable segregation of the resulting mixture into a hydrocarbon phase and a glycol phase. The hydrocarbon phase is separated from the glycol phase and said glycol phase is desalted, e.g. by electrodialysis, to give a desalted and substantially hydrocarbon-free glycol solution which is then concentrated by steam stripping. The method is useful for purifying waste glycol solutions resulting from oil or gas production effluent processing using glycols, and in particular from a gas hydrate inhibition treatment or natural gas dehydration.

Abstract: Disclosed is a method of reducing the UV absorption of a solvent that comprises water, an ethylene glycol, or a mixture thereof, where the solvent contains at least 0.1 ppm of a dione, particularly 3-methyl-2-hydroxy cyclopent-2-eneone or its tautomer, 3-methyl-1, 2-cyclopentanedione. The solvent is passed through an anionic exchange resin containing strong base sites. The UV absorbance of the effluent from the anionic exchange resin can be monitored and, when it increases, the resin can be reactivated by passing an aqueous solution of a base through it.

Abstract: Impurities are separated from aqueous solutions of 1,6-hexanediol or 1,6-hexanediol precursors, such as adipic and 6-hydroxycaproic acid, by a process which comprises adding at least one carboxylic acid to a solution (a) of 1,6-hexanediol and subjecting this solution (a) or a solution (b) containing carboxylic acid(s) as precursor(s) of 1,6-hexanediol to a heat treatment at temperatures above room temperature in the absence of hydrogen.

Abstract: A process for preparing a recyclate polyol obtained from glycolysis of polyurethanes and/or polyurea-polyurethanes comprises reacting scrap polyurethane and/or polyurea-polyurethane with a short-chain compound containing at least 2 OH groups in the presence of a catalyst and admixing a cyclic carbonate. The process results in a recyclate polyol having a low primary aromatic amine content which may be used to produce cellular or non-cellular polyurethanes, polyurea-polyurethanes, or polyisocyanurates.

Abstract: A process for preparing diglycerol in high concentrations and high yields by partially reacting glycerol in the presence of an alkaline catalyst to form a reaction mixture containing from 10 to 15% by weight of diglycerol and separating the unreacted glycerol from the reaction mixture in a wiped film or short path first distillation zone at a reduced pressure of 0.5 to 5 mbar and distilling a bottoms product from the first distillation zone in a second distillation zone which is a short path distillation zone at a pressure of 0.05 to 0.3 mbar to obtain a second bottom product containing at least 90% by weight diglycerol. Diglycerol of higher purity can be obtained by recovering diglycerol as a distillate from a third distillation zone.

Abstract: A method for the recovery of glycols from used antifreeze compositions by distillation entails the used antifreeze composition being treated before and/or during its distillation with an effective amount of sulfamic acid.

Abstract: The present invention relates, in general, to a purification process, and particular, to a process of removing cyclic alkane alcohols from compositions comprising linear alkane alcohols.

Abstract: A safe and reliable method of decomposing halogenated aromatic compounds, wherein a heat-resistant alkaline polar solvent containing halogenated aromatic compounds is contacted with a alkali at a temperature ranging from about 100.degree. C. to 300.degree. C. in order to decompose the halogenated aromatic compounds. The used solvent is removed of solid contents of salts, alkalis and the like, whereby it can be recycled.

Abstract: The present invention relates to a process for the production of hydroxyl-group-containing compounds suitable for the polyisocyanate polyaddition process from polyurea and/or polyurethane polyurea wastes by treating polyurea and/or polyurethane polyurea wastes with diols and/or polyols at temperatures from 160.degree. to 260.degree. C., the water present in the reaction vessel preferably being removed by distillation during the heating-up phase, characterized in that 1,3-dicarbonyl compounds are added to the reaction mixture before or during the reaction.

Abstract: A process for separating a first component of a process stream from a second component of a process stream in a single vessel has been developed. The separation process uses an apparatus having a distillation zone to separate a first component from a second component of a process stream, thereby producing a distillation zone overhead stream enriched in the first component, and a membrane separation zone containing a membrane capable of selectively removing additional amounts of the second component from the distillation overhead stream. The benefit is the production of a high purity process at lower capital equipment costs.

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: Recovery of ethylene glycol from dilute aqueous solutions is accomplished by passing the solution over the surface of a porous hydrophobic membrane capable of passing water vapor but not liquid water. The pressure and temperature provide a positive driving force for the movement of water vapor through the membrane to the opposite face where it is removed by condensation or a stream of gas or liquid. Preliminary concentration of the aqueous solutions may be provided by use of reverse osmosis membrane. The method is useful in the reclamation of spent deicing fluid.