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.

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: A method for reducing the particle size of amino acid crystals using ultrasound is discussed.

Abstract: The present invention relates to a process for crystallizing small particles with a narrow particle size distribution. The crystals of the invention are obtained by introducing ultrasound into a solution or suspension of the substance to be crystallized while simultaneously adjusting a particular specific stirring power.

Abstract: A method for reducing the particle size of amino acid crystals using ultrasound is discussed.

Abstract: A method for reducing the particle size of amino acid crystals using ultrasound is discussed.

Abstract: A process for preparing trioxane by trimerization of formaldehyde in aqueous acidic solution and subsequently removing trioxane from a mixture substantially comprising trioxane, water and formaldehyde (crude trioxane product), which comprises a) distilling the crude trioxane product from the trimerization, b) crystallizing the trioxane out and c) removing it from the mother liquor and d) subsequently melting it and e) distilling off further by-products.

Abstract: A process for the isolation of salts of organic acids from an aqeuous solution, in particular from a fermentation discharge, by partial evaporative crystallization and subsequent or simultaneous displacement precipitation of its salts, and for the liberation of the organic acid from the crystals, preferably by means of an electromembrane process, is described.

Abstract: Pure triethylenediamine (TEDA) is prepared by vaporizing TEDA, introducing the gaseous TEDA into a liquid solvent and subsequently crystallizing the TEDA from the solution obtained in this way.

Abstract: A method for reducing the particle size of amino acid crystals using ultrasound is discussed.

Abstract: Polymethylolalkanoic or monomethylolalkanoic acids of the formula (I) 1

Abstract: The present invention relates to a process for crystallizing small particles with a narrow particle size distribution. The crystals of the invention are obtained by introducing ultrasound into a solution or suspension of the substance to be crystallized while simultaneously adjusting a particular specific stirring power.

Abstract: Dicarboxylic acid crystals are prepared from a solution containing at least one organic dicarboxylic acid in a process in which at least one anionic polyelectrolyte having a molecular weight of at least 2000 is added to the solution before or during the crystallization.

Abstract: In a process and an apparatus for avoiding encrustations in reactors or crystallizers (13), such as industrial crystallizers for suspensions (11), points of incidence (4) for the excitation of ultrasonic oscillations by sonotrodes (3) which are connected to electromechanical converters (2) are provided on the walls (6, 21) and on the base (7) of the crystallizer (13). The ultrasonic frequency is generated at high-frequency generators (1).