Abstract: The present invention relates to a process for producing menthol particles stabilized against caking, wherein menthol particles are, following shaping, stored for at least 7 days at a temperature of 0 to 30° C., after which the menthol particles are supplied with a minimum input of mechanical energy. The present invention further relates to storage-stable menthol particles and to the use of said menthol particles in household and consumer goods of all kinds.

Abstract: Process for precipitating a carbonate or (oxy)hydroxide comprising nickel from an aqueous solution of a nickel salt wherein such process is carried out in a vessel comprising (A) a vessel body, (B) one or more elements that control the hydraulic flow of the slurry formed during the precipitation and that induce a loop-type circulation flow, and (C) a stirrer whose stirrer element is in the vessel but located separately from the element(s) (B).

Abstract: The present invention relates to a process for enriching enantiomers from an enantiomer mixture by a fractionating melt crystallization in a melt crystallization apparatus. The invention specifically relates to a process for producing an enantiomer-enriched chiral terpene, in particular of D/L-Isopulegol. The process comprises: i) a crystallization step to obtain a crystallizate and a mother melt and removal of the mother melt from the crystallizate to afford a mother melt fraction; ii) sweating of the crystallizate obtained in step i) to afford a molten sweating fraction and iii) subsequent melting of the sweated crystallizate to afford a molten crystallizate fraction, wherein the optical rotation at least of the sweating fraction is determined online using a polarimeter and the changeover from step ii) to step iii) is controlled online by means of at least one control unit.

Abstract: The present invention relates to a method for separating off a substance from a solution, in which electromagnetic radiation is radiated into the solution, an intensity of the electromagnetic radiation which has been scattered by crystals located in the solution is detected, the detected intensity is compared with a desired intensity (IS) and the temperature of the solution is regulated depending on the difference between the detected intensity and the desired intensity (IS) in such a way that the amount of this difference is reduced. If the amount of the difference between the detected intensity and the desired intensity (IS) is less than a limiting value, a crystallization method is started in which crystals of the substance are obtained which are then separated off.

Abstract: The present invention relates to a particularly economic overall method for producing menthol, specifically for producing optically active, essentially enantiomerically and diastereomerically pure L-menthol and racemic menthol, starting from the starting material citral which is available inexpensively on an industrial scale. The method has the following steps a.1) catalytic hydrogenation of neral and/or geranial to give citronellal, b.1) cyclization of citronellal to isopulegol in the presence of an acidic catalyst, c.1) purification of isopulegol by crystallization and d.1) catalytic hydrogenation of isopulegol to give menthol.

Abstract: Mixture of L- and D-enantiomers of methyl glycine diacetic acid (MGDA) or its respective mono-, di or trialkali metal or mono-, di- or triammonium salts, said mixture containing predominantly the respective L-isomer with an enantiomeric excess (ee) in the range of from 10 to 75%.

Abstract: The present invention relates to novel crystalline modifications of pyraclostrobin, to processes for their preparation and to the use of the novel modifications for preparing crop protection compositions.

Abstract: The present invention relates to a particularly economic overall method for producing menthol, specifically for producing optically active, essentially enantiomerically and diastereomerically pure L-menthol and racemic menthol, starting from the starting material citral which is available inexpensively on an industrial scale. The method comprises the following steps a.1) catalytic hydrogenation of neral and/or geranial to give citronellal, b.1) cyclization of citronellal to isopulegol in the presence of an acidic catalyst, c.1) purification of isopulegol by crystallization and d.1) catalytic hydrogenation of isopulegol to give menthol.

Abstract: The present invention relates to a particularly economic overall method for producing menthol, specifically for producing optically active, essentially enantiomerically and diastereomerically pure L-menthol and racemic menthol, starting from the starting material citral which is available inexpensively on an industrial scale. The method comprises the following steps a) catalytic hydrogenation of neral and/or geranial to give citronellal, b) cyclization of citronellal to isopulegol in the presence of an acidic catalyst, c) purification of isopulegol by crystallization and d) catalytic hydrogenation of isopulegol to give menthol.

Abstract: The present invention relates to a method for preparing L-menthol in solid form, specifically in the form of flakes, by bringing an L-menthol melt into contact with two chilled surfaces distanced from one another. Moreover, the present invention relates to the L-menthol in solid form obtainable by said method, and also to its use for incorporation into utility and consumer goods of all kinds.

Abstract: The present invention relates to a process for preparing enriched isopulegol by crystallization from a melt comprising isopulegol. The invention relates specifically to a process for preparing enantiomerically enriched n-isopulegol proceeding from optically active isopulegol having a relatively low enantiomeric excess by crystallization from the melt. The invention further relates to a process for preparing menthol proceeding from enantiomerically and/or diastereomerically enriched n-isopulegol prepared by crystallization from the melt.

Abstract: The present invention relates to novel crystalline modifications of pyraclostrobin, to processes for their preparation and to the use of the novel modifications for preparing crop protection compositions.

Abstract: The present invention relates to a particularly economic overall method for producing menthol, specifically for producing optically active, essentially enantiomerically and diastereomerically pure L-menthol and racemic menthol, starting from the starting material citral which is available inexpensively on an industrial scale. The method comprises the following steps a.1) catalytic hydrogenation of neral and/or geranial to give citronellal, b.1) cyclization of citronellal to isopulegol in the presence of an acidic catalyst, c.1) purification of isopulegol by crystallization and d.1) catalytic hydrogenation of isopulegol to give menthol.

Abstract: The present invention relates to a method for preparing L-menthol in solid form, specifically in the form of flakes, by bringing an L-menthol melt into contact with two chilled surfaces distanced from one another. Moreover, the present invention relates to the L-menthol in solid form obtainable by said method, and also to its use for incorporation into utility and consumer goods of all kinds.

Abstract: The invention relates to a process for isolating methylglycinenitrile-N,N-diacetonitrile (MGDN) from an aqueous emulsion which comprises MGDN and has an MGDN content of 3-50% by weight in a crystallizer, comprising the steps: (a) the aqueous emulsion is, starting from a temperature above the solidification point, cooled to a temperature below the solidification point, the cooling rate averaged over time not exceeding 5 K/h, until substantially the entirety of the emulsified MGDN has solidified, (b) the resulting aqueous suspension is cooled further and/or concentrated, and the cooling rate may be greater than in step (a).

Abstract: Method of purifying an open-chain N-vinyl compound by crystallization in a crystallizer, the crystallization being carried out from a melt of a mixture comprising open-chain N-vinyl compound at a pressure of 10?3 to 400 bar.

Abstract: The present invention relates to a process for working up triethylenediamine (TEDA) in which TEDA is vaporized and the gaseous TEDA is introduced into a solvent, subsequently crystallized and separated off from this and the mother liquor formed is extracted with an extractant, wherein the raffinate phase obtained after the extraction stage is worked up further by adsorption in which extractant and/or by-products and intermediates present in the raffinate phase are removed therefrom.

Abstract: Alkoxides are isolated by crystallization of an alcohol from a solution in the corresponding alcohol, with the alkoxide being crystallized out at a pressure of at least 3 bar abs. and a temperature of at least 120° C.

Abstract: The present invention relates to novel crystalline modifications of pyraclostrobin, to processes for their preparation and to the use of the novel modifications for preparing crop protection compositions.

Abstract: The present invention relates to a process for preparing enriched isopulegol by crystallization from a melt comprising isopulegol. The invention relates specifically to a process for preparing enantiomerically enriched n-isopulegol proceeding from optically active isopulegol having a relatively low enantiomeric excess by crystallization from the melt. The invention further relates to a process for preparing menthol proceeding from enantiomerically and/or diastereomerically enriched n-isopulegol prepared by crystallization from the melt.