Abstract: The presently claimed invention is directed to a method for the preparation of an aqueous solution comprising at least one beta-glucan comprising at least the steps of a) fermentation of at least one fungal strain in an a fermentation broth, b) addition of at least one acid to the fermentation broth to adjust the pH to a value in the range of ?2.0 to ?4.0 and c) filtration of the fermentation broth to obtain an aqueous solution comprising the at least one beta-glucan and at least one beta-glucan that is obtained by this method.

Abstract: The presently claimed invention is directed to a method for the preparation of an aqueous solution comprising at least one beta-glucan comprising at least the steps of a) fermentation of at least one fungal strain in an a fermentation broth, b) addition of at least one acid to the fermentation broth to adjust the pH to a value in the range of ?2.0 to ?4.0 and c) filtration of the fermentation broth to obtain an aqueous solution comprising the at least one beta-glucan and at least one beta-glucan that is obtained by this method.

Abstract: The present invention relates to an improved process for filtering aqueous fermentation broths comprising glucans and biomass using symmetrical tubular membranes.

Abstract: A process for the preparation of aqueous solutions of glucans having a ?-1,3-glycosidically-linked main chain and side groups having a ?-1,6-glycosidic bond by fermentation of fungal strains. The fungal strains secrete the glucans into the fermentation broth, in an aqueous culture medium, and the separation of the glucans from the fermentation broth is effected using asymmetrical filter membranes.

Abstract: The present invention relates to template-free clathrasils whose framework comprises essentially SiO2, wherein the crystals of the clathrasils have the platelet-like morphology of a sheet silicate. The present invention further relates to a process for preparing these template-free clathrasils and also to their use as absorbent, as seed crystals for the synthesis of clathrasil membranes of the same zeolite type and in the form of dense layers which function as gas separation membranes having a molecular sieving action.

Abstract: The use of solutions of ethylenically unsaturated polyesters for production of carbon membranes suitable for gas separation, and a process for producing carbon membranes suitable for gas separation, comprising the steps of: a) coating a porous substrate with a solution of ethylenically unsaturated polyester, b) drying the polyester coating on the porous substrate by removing the solvent, c) pyrolyzing the polyester coating on the porous substrate to form the carbon membrane suitable for gas separation, it being possible to conduct any of steps a) to c) or the sequence of steps a) to c) more than once.

Abstract: There is described a process for producing carbon membranes suitable for gas separation, comprising the steps of: a) coating a porous substrate with a solution of at least one organic polymer which can be converted to a carbon membrane by pyrolysis, b) drying the polymer coating on the porous substrate by removing the solvent, c) pyrolyzing the polymer coating on the porous substrate to form the carbon membrane suitable for gas separation, it being possible to conduct any of steps a) to c) or the sequence of steps a) to c) more than once, and the pyrolysis in step c) being effected at a temperature higher than the baking temperature of the porous substrate.

Abstract: The present invention relates to template-free clathraslls whose framework comprises essentially SO2, wherein the crystals of the ciathrasils have the platelet-like morphology of a sheet silicate. The present invention further relates to a process for preparing these template-free clathrasils and also to their use as absorbent, as seed crystals for the synthesis of ciathrasil membranes of the same zeolite type and in the form of dense layers which function as gas separation membranes having a molecular sieving action.

Abstract: A process for the preparation of aqueous solutions of glucans having a ?-1,3-glycosidically-linked main chain and side groups having a ?-1,6-glycosidic bond by fermentation of fungal strains. The fungal strains secrete the glucans into the fermentation broth, in an aqueous culture medium, and the separation of the glucans from the fermentation broth is effected using asymmetrical filter membranes.

Abstract: The present invention relates to a continuous process for the preparation of cinnamaldehyde or cinnamaldehyde derivatives by continuous reaction of benzaldehyde derivatives with alkanals in the presence of bases and optionally subsequent continuous hydrogenation in a circulation reactor in the presence of a suspension catalyst and hydrogen to give dihydrocinnamaldehyde derivatives.

Abstract: Described is a process for the preparation of a particulate tetrahydro-3,5-dimethyl-1,3,5-thiadiazine-2-thione product by combining a first aqueous solution comprising methylammonium N-methyldithiocarbamate with a second aqueous solution comprising formaldehyde, followed by separation and drying of the resulting solid, which comprises combining the first and the second aqueous solutions in such a way that the ratio between the concentrations of dithiocarbamate functions and of formaldehyde is essentially constant in the reaction mixture over time during the duration of the reaction.

Abstract: A process for working up distillation residues from the synthesis of tolylene diisocyanate by reaction of the distillation residues with water comprises reacting the TDI distillation residues with water in a continuous or semicontinuous process in a backmixed reactor in the presence of hydrolysate.

Abstract: Described is a process for the preparation of a particulate tetrahydro-3,5-dimethyl-1,3,5-thiadiazine-2-thione product by combining a first aqueous solution comprising methylammonium N-methyldithiocarbamate with a second aqueous solution comprising formaldehyde, followed by separation and drying of the resulting solid, which comprises combining the first and the second aqueous solutions in such a way that the ratio between the concentrations of dithiocarbamate functions and of formaldehyde is essentially constant in the reaction mixture over time during the duration of the reaction.

Abstract: In a process for the continuous preparation of glutaraldehyde by reaction of an alkoxydihydropyran of the formula I where R is C1-C20-alkyl, with water at from 0° C. to 200° C. and a pressure in the range from 0.01 bar to 16 bar to form glutaraldehyde and the alcohol corresponding to the alkoxy group, water and alkoxydihydropyran are fed continuously to a reaction column and a distillate enriched in the alcohol corresponding to the alkoxy group is taken off at the top of the column and a product enriched in glutaraldehyde is taken off at the bottom. This process makes it possible to prepare glutaraldehyde or C-substituted glutaraldehydes continuously in high purity in a simple manner with a low outlay in terms of apparatus.

Abstract: The present invention relates to a continuous process for the preparation of unsaturated acetals by reacting olefinically unsaturated aliphatic compounds with allyl alcohols in a reaction column, where the reactants are only partially reacted in the reaction column, the resulting acetal is concentrated in at least two successive evaporation stages, and the recovered reactants are returned to the reaction column.

Abstract: The present invention relates to a continuous process for the preparation of unsaturated acetals by reacting olefinically unsaturated aliphatic compounds with allyl alcohols in a reaction column, where the reactants are only partially reacted in the reaction column, the resulting acetal is concentrated in at least two successive evaporation stages, and the recovered reactants are returned to the reaction column.

Abstract: In a process for the preparation of methylglyoxal dimethyl acetal from methylglyoxal and methanol in the presence of an acidic ion exchanger, water is introduced in an amount sufficient to form an acidic reaction mixture in which the acetal product and water form an azeotropic mixture, with or without the retention of some methanol reactant. After subjecting a single phase acidic reaction mixture to an azeotropic distillation, it will separate into two distinct liquid phases with a simple recovery of the acetal product from the aqueous phase.

Abstract: A process is described for the continuous preparation of dimethylvinylcarbinol (DMVC) by continuously reacting prenol with the aqueous solution of a protic acid in the still or in the lower part of a rectification column while distilling off the DMVC formed in the form of an azeotropic mixture with water, which comprises a) during the reaction ensuring that as far as possible no liquid two-phase mixture forms in the reaction mixture, b) distilling off the DMVC which forms at a reflux ratio of at least 2, as a result of which there is virtually no more prenol present in the distillate from the column, and c) setting the reaction volume and/or the amount of prenol added per hour and/or the concentration of protons in the reaction mixture in such a manner that the quotient, defined as residence time concentration coefficient, of the reaction volume and the volume of prenol added per hour multiplied by the concentration of protons in the reaction mixture has a value between 0.

Abstract: 3,7-Dimethyl-2,6-octadien-1-al of formula I is prepared continuously by: thermally cleaving, in the presence or absence of an acid catalyst, 3-methyl-2-buten-1-al diprenyl acetal of formula II: thereby eliminating 3-methyl-2-buten-1-ol of formula III and yielding cis/trans-prenyl 3-methylbutadienyl ether of formula IV: thermally rearranging the resultant butadienyl ether of formula IV thereby yielding 2,4,4-trimethyl-3-formyl-1,5-hexadiene of formula V: subsequently rearranging intermediate (V) thereby yielding citral product of formula I, which comprises: as the reaction proceeds, continuously distilling the reaction mixture thereby continuously removing prenol, which is formed by degradation of acetal II, and the intermediates of formula IV and V and any citral product which is formed during the reaction; and thermally rearranging said intermediates of formula IV and V at a temperature of 100-200° C.

Abstract: A process for preparing glyoxal monoacetals of the formula I, ##STR1## where R.sup.1 and R.sup.2, which can be identical or different, are C.sub.1 -C.sub.4 alkyl or C.sub.2 -C.sub.4 alkenyl involves reacting a mixture of glyoxal and glyoxal bisacetals of the formula II, ##STR2## where R.sup.1 and R.sup.2 have the meaning given above, with an excess of an alcohol of the formula R.sup.1 OH or R.sup.2 OH or mixtures of these in the presence of an acid catalyst until reaction equilibrium is achieved.