Abstract: A method for producing a cyclic ether represented by formula (2) includes reacting a 2-hydroxy cyclic ether, represented by formula (1), with hydrogen in the presence of a catalyst.

Abstract: The present invention provides a high-molecular-weight polyether polyol ensuring that when used as a polyurethane raw material, a polyurethane having excellent flexibility and elastic recovery can be obtained; and a method for producing, with high productivity, a polyether polyol having a higher number average molecular weight and a narrower molecular weight distribution than those of the raw material polyether polyol, and the polyether polyol of the present invention has a number average molecular weight of 3,500 to 5,500 and a molecular weight distribution of 1.7 to 3.0.

Abstract: The present invention is concerned with a method for producing tetrahydrofuran including carrying out a dehydration cyclization reaction of 1,4-butanediol in the presence of an acid catalyst having a pKa value of not more than 4 within a reactor, wherein a raw material liquid containing 1,4-butanediol to be provided for the reaction contains from 0.01 to 0.35% by weight of 2-(4-hydroxybutoxy)-tetrahydrofuran and 1 ppm by weight or more and not more than 1,000 ppm by weight of at least one of an amine and an amide in terms of a concentration as converted into a nitrogen atom.

Abstract: The present invention relates to a method for producing tetrahydrofuran, comprising feeding 1,4-butanediol to a reactor and performing a cyclodehydration reaction in the presence of an acid catalyst to obtain tetrahydrofuran, in which a water concentration in a in-reactor liquid phase is within a range of 1.4 to 10 wt %.

Abstract: The present invention relates to a method for producing tetrahydrofuran comprising: feeding raw material 1,4-butanediol containing gamma butyrolactone to a reaction tank, and performing a dehydration cyclization reaction in the presence of a homogeneous acid catalyst having a pKa of 4 or less and being dissolvable in 1,4-butanediol to produce tetrahydrofuran, wherein a gas containing tetrahydrofuran, gamma butyrolactone and water in the reaction tank is introduced into a heat exchanger and when obtaining a condensate from the outlet of the heat exchanger, the ratio of the concentration of gamma butyrolactone in the condensate based on the concentration of gamma butyrolactone in the raw material 1,4-butanediol is from 20 to 100%.

Abstract: Processes are described for producing furfural from a mixture of pentoses and hexoses, by dehydrating and cyclizing pentoses to provide furfural using a water-soluble acid at elevated temperatures in the presence of a low-boiling, water-immiscible organic solvent, such as toluene, which is effective for extracting the furfural into an organic phase portion. In certain embodiments, a fermentation step occurs prior to the dehydration step to convert hexoses in the mixed pentoses and hexoses to ethanol while conserving pentoses therein for making furfural.

Abstract: A method of making an anti-Markovnikov addition product is carried out by reacting an acid with an alkene or alkyne in a dual catalyst reaction system to the exclusion of oxygen to produce said anti-Markovnikov addition product; the dual catalyst reaction system comprising a single electron oxidation catalyst in combination with a hydrogen atom donor catalyst. Compositions useful for carrying out such methods are also described.

Abstract: Provided are catalysts suitable for the production of tetrahydrofuran from 1,4-butanediol. Also provided are methods of use of these catalyst, as well as catalyst systems. The catalysts described herein contain only Lewis acidity, but not Broønsted acidity, which results in decreased production of ether byproducts.

Abstract: The present invention relates to a method of producing bio-based homoserine lactone and bio-based organic acid through hydrolysis of O-acyl homoserine produced by a microorganism in the presence of an acid catalyst. According to the present invention, O-acyl homoserine produced by a microorganism is used as a raw material for producing 1,4-butanediol, gamma-butyrolactone, tetrahydrofuran and the like, which are industrially highly useful. The O-acyl homoserine produced by a microorganism can substitute conventional petrochemical products, can solve environmental concerns, including the emission of pollutants and the exhaustion of natural resources, and can be continuously renewable so as not to exhaust natural resources.

Abstract: The present invention is concerned with a method for producing tetrahydrofuran including carrying out a dehydration cyclization reaction of 1,4-butanediol in the presence of an acid catalyst having a pKa value of not more than 4 within a reactor, wherein a raw material liquid containing 1,4-butanediol to be provided for the reaction contains from 0.01 to 0.35% by weight of 2-(4-hydroxybutoxy)-tetrahydrofuran and 1 ppm by weight or more and not more than 1,000 ppm by weight of at least one of an amine and an amide in terms of a concentration as converted into a nitrogen atom.

Abstract: The present invention relates to a method for producing tetrahydrofuran comprising: feeding raw material 1,4-butanediol containing gamma butyrolactone to a reaction tank, and performing a dehydration cyclization reaction in the presence of a homogeneous acid catalyst having a pKa of 4 or less and being dissolvable in 1,4-butanediol to produce tetrahydrofuran, wherein a gas containing tetrahydrofuran, gamma butyrolactone and water in the reaction tank is introduced into a heat exchanger and when obtaining a condensate from the outlet of the heat exchanger, the ratio of the concentration of gamma butyrolactone in the condensate based on the concentration of gamma butyrolactone in the raw material 1,4-butanediol is from 20 to 100%.

Abstract: Processes and methods for making biobased tetrahydrofuran products from renewable carbon resources are described herein.

Abstract: Provided are catalysts suitable for the production of tetrahydrofuran from 1,4-butanediol. Also provided are methods of use of these catalyst, as well as catalyst systems. The catalysts described herein contain only Lewis acidity, but not Brønsted acidity, which results in decreased production of ether byproducts.

Abstract: Disclosed are: a ligand for an asymmetric synthesis catalyst; and a process for producing an ?-alkenyl cyclic compound using the ligand. Specifically disclosed are: a ligand for an asymmetric synthesis catalyst, which is represented by any one of formulae (1) to (4) [wherein R1 represents —Cl or —Br; R2 represents —CH3 or —CF3; and R3 represents —CH2—CH?CH2 or —H]; and a process for producing an ?-alkenyl cyclic compound using the ligand.

Abstract: The present invention relates to a process for the catalytic hydrogenation of 1,4-butynediol to tetrahydrofuran at at least the decomposition temperature of 1,4-butynediol, wherein 1,4-butynediol is vaporized in a hydrogen-comprising gas stream and is hydrogenated in gaseous form over at least one catalyst, comprising at least one of the elements from groups 7 to 11 of the Periodic Table of the Elements.

Abstract: Process for preparing tetrahydrofuran, 1,4-butanediol and/or gamma-butyrolactone by hydrogenation of 1,4-butynediol, wherein 1,4-butynediol is vaporized in a hydrogen-comprising gas stream and hydrogenated in gaseous form over at least one catalyst which comprises at least one of the elements of groups 7 to 11 of the Periodic Table of the Elements.

Abstract: Processes and reactor systems are provided for the conversion of oxygenated hydrocarbons to hydrocarbons, ketones, cyclic ethers and alcohols useful as liquid fuels, such as gasoline, jet fuel or diesel fuel, and industrial chemicals. The process involves the conversion of oxygenated hydrocarbons, such as alcohols, ketones, aldehydes, furans, carboxylic acids, diols, triols, and/or other polyols, to C4? hydrocarbons, cyclic ethers, alcohols and/or ketones, by condensation and/or deoxygenation. The oxygenated hydrocarbons may originate from any source, but are preferably derived from biomass.

Abstract: Three biosynthetic pathways are disclosed for microorganism bio-production of 1,4-Butanediol from various carbon sources. Exemplary methods are provided. The recombinant microorganisms comprising any of these 1,4-Butanediol biosynthesis pathways may also comprise genetic modifications directed to improved tolerance for 1,4-Butanediol.

Abstract: A process of preparing cyclic ethers is described. The process involves the reaction of at least one organic compound such as a dioi or a polyol which it has at least one pair of hydroxyl groups separated by 4 or 5 carbon atoms, and which is capable of being converted into an ether linkage, with an organic carbonate in the presence of a base. The base is an alkoxy, a carbonate or a hydroxide base or is a mixture of such bases. At least one of the hydroxyl groups of the organic compound is not a tertiary hydroxyl group.

Abstract: A process for obtaining oligomers of polytetrahydrofuran or of tetrahydrofuran copolymers from a methanolic crude product which contains polytetrahydrofuran or tetrahydrofuran copolymers and is obtained in the transesterification of the mono- and/or diesters of polytetrahydrofuran or tetrahydrofuran copolymers with methanol, which includes a) removing the majority of the methanol from the crude product in a first distillation stage, b) separating the resulting bottom product by distillation into a top fraction containing the oligomers of polytetrahydrofuran or of tetrahydrofuran copolymers, and polytetrahydrofuran or tetrahydrofuran copolymer, and c) condensing the oligomers of polytetrahydrofuran or of tetrahydrofuran copolymers out of the top fraction from stage b).

Abstract: The method of the invention for continuously producing 2,5-dihydrofuran includes subjecting cis-2-butene-1,4-diol to liquid-phase dehydration-cyclization reaction in the presence of alumina, characterized in that the sum of the concentration of carbonyl compounds present in the reaction system and the concentration of acetal compounds present in the reaction system is controlled to fall within a range of 0.1 to 2 mol/L, provided that the concentration of the acetal compounds is calculated in terms of acetal groups, the concentrations being determined on the basis of the total amount of the reaction mixture. According to the method, 2,5-dihydrofuran, which is useful as a raw material or intermediate for producing pharmaceuticals, agrochemicals, raw materials of polymers, etc., can be continuously produced. The method can prevent inactivation of ?-alumina and is advantageous for long-term production on an industrial scale.

Abstract: The present invention provides a process for distillatively purifying tetrahydrofuran in the presence of a polar solvent.

Abstract: Provided is a method for the production of tetrahydrofuran (THF) from 1,4-butanediol (BDO) using a zirconium sulfate (Zr(SO4)2.nH2O) catalyst. The method of the present invention can achieve high-yield production of tetrahydrofuran via a simple and low-risk production process by dehydration of 1,4-butanediol in the presence of a zirconium sulfate catalyst.

Abstract: The present invention relates to a process for preparing tetrahydrofuran from 1,4-butandiol. According to the process in the present invention, a metal sulfate catalyst selected from the group consisting of aluminum sulfate, nickel sulfate, ferrous sulfate and chrome sulfate is pre-treated with an inert gas to be activated, followed by introducing into a reactor together with 1,4-butandiol.

Abstract: Provided is a method for the production of tetrahydrofuran (THF) from 1,4-butanediol (BDO) using a zirconium sulfate (SO42?/ZrO2) catalyst. The method of the present invention can achieve high-yield production of tetrahydrofuran via a simple and low-risk production process by dehydration of 1,4-butanediol in the presence of a zirconium sulfate catalyst.

Abstract: Crude water-containing tetrahydrofuran is purified by passing the crude tetrahydrofuran through three distillation columns, withdrawing water from the bottom of the first column, recycling water-containing tetrahydrofuran from the top of the second column into the first column, passing a sidestream of the first column into the second column, recycling the bottom product of the third column into the first column, and withdrawing a distillate at the top of the first column. Additionally, a sidestream of the second column is passed into the third column and the purified tetrahydrofuran is recovered as the top product of the third column.

Abstract: The invention provides a process for preparing polytetrahydrofuran, tetrahydrofuran copolymers, their monoesters or diesters and the monoesters or diesters of polytetrahydrofuran having a low color number in the presence of a catalyst, which comprises converting crude tetrahydrofuran which has been prepared in a manner per se into pure tetrahydrofuran by distillation, subsequently subjecting the latter to essentially complete hydrogenation and using the high-purity tetrahydrofuran obtained in this way for the polymerization directly after its preparation.

Abstract: The invention relates to a process for the continuous preparation of THF by reaction of a 1,4-butanediol-containing reaction mixture over a heteropolyacid catalyst which has not been predried, wherein the reaction mixture comprises 2-(4-hydroxybutoxy)tetrahydrofuran.

Abstract: Disclosed is a method for the hydrogenation of tetrahydroxybutane in the presence of supported rhenium catalysts and an acid to form tetrahydrofuran and its precursors.

Abstract: In a process for preparing polytetrahydrofuran, tetrahydrofuran copolymers, diesters or monoesters of these polymers having a low color number, the polymers obtained by cationic polymerization of tetrahydrofuran are hydrogenated in the presence of a macroporous, supported heterogeneous catalyst comprising at least one metal of groups 7 to 10 of the Periodic Table of the Elements as active metal.

Abstract: A process for the co-production of a diol product (e.g. butane-1,4-diol) and a cyclic ether (e.g. tetrahydrofuran) by hydrogenation of an aliphatic diester or lactone feedstock (e.g. dimethyl or diethyl maleate), which contains a minor amount of acidic material, such as the corresponding monoester. The process utilizes a plurality of hydrogenation zones connected in series, each containing a charge of a granular ester hydrogenation catalyst. The catalyst in the first hydrogenation zone is tolerant of a minor amount of acidic material, while the catalyst in the second hydrogenation zone provides enhanced yields of cyclic ethers compared to the catalyst of the first hydrogenation zone. The catalyst in a third hydrogenation zone exhibits low selectivity towards conversion of the diester to at least one by product (e.g. 2-4?-hydroxybutoxy-tetrahydrofuran).

Abstract: A method for producing a saturated cyclic ether from a fatty acid ester of an &agr;, &dgr;-diol stably in high yield over a long period of time, is presented. It is a process for producing a saturated cyclic ether, which comprises reacting a mono- and/or di-fatty acid ester of an &agr;, &dgr;-diol in the presence of a solid acid catalyst, wherein the reaction is carried out in such a state that at least 50 mol % of the fatty acid ester supplied to the reaction system is vaporized.

Abstract: Disclosed is a method whereby 3,4-tetrahydrofurandiol is hydrogenated in the presence of Rh, Re, Pd, Ru and Ni catalysts, optionally supported, to form tetrahydrofuran and its precursors.

Abstract: Disclosed is a process for the preparation of 3-methyltetrahydrofuran (MeTHF) from 3-(hydroxymethyl)tetrahydrofuran (HOMeTHF) by contacting HOMeTHF with hydrogen in the presence of an acidic, supported catalyst comprising a Group VIII metal.

Abstract: Processes are disclosed for the preparation of 2-methylfuran and 2-methyltetrahydrofuran. The continuous vapor-phase processes are commercially viable and efficient because they permit the preparation of 2-methylfuran and 2-methyltetrahydrofuran using commercially-available catalysts, namely, a reduced copper-based catalyst consisting essentially of cupric oxide, chromium (III) oxide, manganese oxide and barium chromate and a reduced nickel-based catalyst consisting essentially of nickel, nickel (II) oxide, aluminum oxide and silica. An apparatus comprising two inline hydrogenators is used for preparing the 2-methylfuran or 2-methyltetrahydrofuran.

Abstract: The invention discloses a method for depolymerization of a mixture containing polytetrahydrofuran derivatives, including heating the mixture comprising polytetrahydrofuran derivatives at 100-250° C. in the presence of a &bgr;-zeolite catalyst to obtain tetrahydrofuran, whereby the tetrahydrofuran monomer can be recovered from the waste materials in the preparation of polytetramethylene ether glycols.

Abstract: The present invention relates to a catalytic process for the preparation of 3-hydroxymethyl tetrahydrofuran of formula IV with hydroformylation as one of the key steps. The process comprises reacting 9-hydroxymethyl-7,12-dioxaspiro[5,6]dodecane of the formula III with an alcohol in the presence of an acid catalyst and recovering the 3-hydroxymethyl tetrahydrofuran.

Abstract: A two-stage process for producing tetrahydrofuran and gammabutyrolactone in varying proportions from maleic, succinic anhydride or fumaric acid esters, by vapor phase hydrogenation. The first stage occurs on a copper-based catalyst to produce a mixture of tetrahydrofuran, gammabutyrolactone and butanediol. The second stage occurs on an acidic silica rich silica-alumina type catalyst to convert butanediol to tetrahydrofuran.

Abstract: The functionalization of compounds containing carbon-hydrogen bonds utilizing platinum compounds in Shilov-type reactions is improved by using hydrogen peroxide or selected Pt[IV] compounds as an oxidant.

Abstract: Process and arrangement for producing tetrahydrofuran from a hydrous butane diol solution contaminated by light volatile, organic compounds, comprising the following process stages: a) Distillative removal (K1) of the light volatile, organic compounds contained in the hydrous butane diol solution 1. b) Dehydrating (R) of the thus prepurified hydrous butane diol solution 3 over an acidic aluminum oxide catalyst. c) One-step or multi-step distillation (K2) of the thus obtained high-tetrahydrofuran fraction 8 for obtaining a pure tetrahydrofuran. In addition, a separation of the water from the hydrous butane diol solution to water contents of from 2 to 70% by weight, particularly 2 to 10% by weight, can take place before the dehydrating of the butane diol.

Abstract: Tetrahydrofurans suitable for use as starting materials in the synthesis of polyether polyols without causing coloration in the product polyether polyols can be obtained by contacting crude tetrahydrofurans with a mineral acid or a strongly acidic cation-exchange resin, followed by isolation through a simple distillation and/or rectification to obtain purified tetrahydrofurans.

Abstract: A process for preparing tetrahydrofuran, which comprises reacting 1,4-butenediol diethers of the formulae I and/or II RO—CH2—CH═CH—CH2—OR  I RO—CH2—CH2═CH—CH2—OR  II, where the R radicals can be identical or different and are C1-C15-alkyl or cycloalkyl radicals, C6-C12-aryl radicals or C7-C15-aralkyl radicals, with water and hydrogen at from 20 to 300° C. under from 1 to 300 bar in the presence of catalysts or catalyst combinations which comprise components which are both capable of hydrogenation and have acidic or basic centers and a novel process for preparing 1,4-butanediol diethers of the formula I by metathesis are described.

Abstract: A method and apparatus for recycling and recovering potentially explosive solvents includes providing a contaminated solvent to a distillation tank, vaporizing the solvent in the distillation tank, thereby producing solvent vapor, condensing the solvent vapor, and adding a free radical scavenger substance to the distillation tank during the heating step. The vapor is then condensed and collected in a clean solvent tank where additional free radical scavenger substance is added to the clean solvent tank. Preferably, contaminated solvent is introduced into the solvent recovery system by providing contaminated solvent into contaminated solvent tank which is connected to the distillation tank, and an oxygen displacer substance is provided to the contaminated solvent tank and the clean solvent tank so as to minimize the amount of free oxygen in the tanks.

Abstract: Disclosed is a process for the preparation of 3-methyltetrahydrofuran (3-MeTHF) from 3-(hydroxymethyl)tetrahydrofuran (3-HOMeTHF) by a plurality of process steps comprising (1) esterifying 3-HOMeTHF to produce a carboxylate ester of 3-HOMeTHF, (2) pyrrolyzing the carboxylate ester to produce 3-methylenetetrahydrofuran (3-methyleneTHF), and (3) hydrogenating the 3-methyleneTHF to produce 3-MeTHF. The 3-MeTHF produced in accordance with the present invention is useful as an industrial solvent and as a monomer in the manufacture of polymers such as elastomers.

Abstract: Process for producing coatings or moldings by radiation curing, which involves using high-energy light to irradiate radiation-curable compositions containing 1-100% by weight, based on the total amount of free-radically or cationically polymerizable compounds, of compounds A) containing at least one cationically polymerizable 2,3-dihydrofuran group.

Abstract: This invention is directed to a process for producing cyclic ethers by liquid phase reaction, which comprises using a crystalline aluminosilicate zeolite as the catalyst, and subjecting an alkanediol to cyclodehydration at a temperature less than the boiling point of the alkanediol to obtain the corresponding cyclic ether.

Abstract: A process for hydrogenating aqueous mixtures of 4-hydroxybutanal and 3-hydroxy-2-methylpropanal is disclosed. The process uses a metallic Pt--Ru catalyst supported on .gamma.-alumina. The process gives improved yields of 2-methyl-1,3-propanediol while minimizing the formation of unwanted by-products such as isobutyl alcohol and tetrahydrofuran.

Abstract: Disclosed is a two-step process wherein (1) 2,3-dihydrofuran is reacted with a trialkyl orthoformate in the presence of an acidic catalyst to produce a 2-alkoxy-3-(dialkoxymethyl)tetrahydrofuran intermediate and (2) the intermediate is contacted with hydrogen in the presence of a catalyst system comprising a Group VIII noble metal or rhenium and a strong acid to convert the intermediate to a mixture of 3-methyltetrahydrofuran (3-MeTHF) and 3-(hydroxymethyl)tetrahydrofuran (3-HOMeTHF). The 3-MeTHF produced in accordance with the present invention is useful as an industrial solvent and as a co-monomer in the manufacture of polymers such as elastomers. 3-HOMeTHF may be used as a solvent and in the manufacture of pharmaceutical and agricultural chemicals and acrylate and methacrylate esters for use in preparing polymers such as polyacrylates.

Abstract: The present invention relates to the epoxidation of olefins using cyclohexyl hydroperoxide as reactant, the improvement being using a secondary or tertiary alcohol such as cyclohexanol or tertiary butyl alcohol as a stabilizing agent during the epoxidation, the alcohol stabilizer being fed to the epoxidation reaction zone in an amount greater than 3 moles per mole of hydroperoxide fed to the epoxidation reaction zone.

Abstract: A process is disclosed for separating a mixture of methanol and tetrahydrofuran into its components. The separation is carried out in the liquid or gaseous phase through an organophilic membrane, for example, a plasma polymerization membrane.