Abstract: A process for removing precursors, such as low boiling alkyl glycols (e.g., ethylene glycol and/or 1,2-propylene glycol), to undersirable color forming acetal impurities (e.g., 1,3 -dioxolane and 4-methyl-1,3-dioxolane) from technical grade 1,4-butanediol/2-methyl-1,4-butanediol mixtures and the like by distillative topping of the diol mixture prior to ring closing cyclization to corresponding tetrahydrofuran/3-methyl tetrahydrofuran mixture and subsequent polymerization to polytetramethylene glycol ether polymers. Such a process is useful to produce THF and PTMEG having a APHA color index of nearly zero.

Abstract: A process for reducing fluoride levels in PTMEG by heating aqueous PTMEG having an undesired level of fluoride (80'600 ppm) to a temperature in the range between about 200.degree. and 300.degree. C. for a period of time sufficient to reduce the fluoride content of said PTMEG. Preferably, heating is carried out with agitation to a temperature between about 225.degree. and about 275.degree. C. for about 1 minute to about 8 hours in the presence of an aqueous base, most preferably 240.degree. to 250.degree. C. in presence of aqueous lime.

Abstract: Process for preparing 2-alkyl-1,4-butanediols and mixtures with 1,4-butanediol which comprises bringing together, at an initial alkaline pH, and at a temperature and pressure suitable for reaction, a mixture of 4-hydroxybutyraldehyde and/or its cyclic acetal, 2-hydroxytetrahydrofuran, hydrogen, an unsubstituted aliphatic aldehyde, especially formaldehyde, and a hydrogenation catalyst. Also processes for preparing mixtures of tetrahydrofuran and 3-alkyltetrahydrofuran from the diol mixtures, and copolymers from the tetrahydrofuran mixtures.

Abstract: Process for preparing 2-alkyl-1,4-butanediols and mixtures with 1,4-butanediol which comprises bringing together, at an initial alkaline pH, and at a temperature and pressure suitable for reaction, 2,3-dihydrofuran, hydrogen, an unsubstituted aliphatic aldehyde, especially formaldehyde, and a hydrogenation catalyst. Also processes for preparing mixtures of tetrahydrofuran and 3-alkyltetrahydrofuran from the diol mixtures, and copolymers from the tetrahydrofuran mixtures.

Abstract: A mixture of 1,4-butanediol and 2-alkyl-1,4-butanediol is produced by catalytic hydrogenation and reaction with an aldehyde. Such mixture is cyclized to a mixture of tetrahydrofuran and 3-alkyl tetrahydrofuran. Copolymers can then be made from such mixtures of furans.

Abstract: 2-Alkyl-1,4-butanediols are prepared from 1,4-butynediol or 1,4-butenediol by catalytic hydrogenation and reaction with an aldehyde.

Abstract: The hydrogenation of furan to tetrahydrofuran can be carried out simultaneously with the hydrogenation of 2-butyne-1,4-diol to 1,4-butanediol. This can be done in the same reactor, using a common catalyst, and under common reaction conditions.

Abstract: The amount of methacrolein impurity in tetrahydrofuran made from acetylene and formaldehyde can be significantly reduced by treating it with hydrogen peroxide during an interval in the multi-stage distillation tetrahydrofuran refining procedure.

Abstract: Color-forming materials or their precursors present in crude 1,4-butanediol are reduced more efficiently by subjecting the crude 1,4-butanediol to distillation under conditions wherein substantially all the water present in the crude 1,4-butanediol is first removed and then the 1,4-butanediol with reduced water content is further distilled to remove the color-forming materials.