摘要:
A process for heterogeneously catalyzed gas phase partial oxidation of an organic starting compound over a fixed catalyst bed freshly installed into a reaction chamber, in which the reduction in the quality of the fixed catalyst bed is restored with increasing operating time by replacing a portion of the fixed catalyst bed by a replacement fixed catalyst bed part whose volume-specific activity is lower than the volume-specific activity of the replaced fixed catalyst bed part in its freshly installed state.
摘要:
A process for starting-up a heterogeneously catalyzed partial gas phase oxidation of acrolein to acrylic acid or of methacrolein to methacrylic acid over a fixed catalyst bed disposed in a tube bundle reactor cooled by a heat exchange medium, wherein the temperature of the heat exchange medium is ≧290° C. and the temperature of that reactor plate surface which faces the reaction gas entry mixture and the temperature of the reaction gas entry mixture itself are ≦285° C.
摘要:
Apparatus for the long-term operation of a heterogeneously catalyzed gas phase partial oxidation of at least one organic compound over a catalyst bed, in which, in order to counteract the deactivation of the catalyst bed, the working pressure in the gas phase is increased during the operating time of the catalyst bed.
摘要:
A process for preparing an organic target compound by heterogeneously catalyzed gas phase partial oxidation of an organic precursor compound with molecular oxygen in two oxidation reactor lines operated in parallel and removal of the target compound from the mixture of the product gas streams in a workup line, wherein the catalysts charge of one of the oxidation lines comprises a portion of catalyst over which the heterogeneously catalyzed gas phase partial oxidation has already been carried out for longer than over the portions of catalyst of the catalyst charge of the other oxidation reactor line.
摘要:
A process for transporting a liquid monomer phase which has been withdrawn from a storage vessel and comprises methacrylic monomers to an extent of ≧90% by weight, in a tank truck or in a tanker ship, in which the liquid monomer phase is subjected to a separating operation on the route from the storage vessel into the tank of a tank truck or of a tanker ship in order to separate polymer of the monomer present in dissolved form in the liquid monomer phase.
摘要:
A process for purifying removal of acrylic acid, methacrylic acid, N-vinylpyrrolidone or p-xylene crystals from their suspension in mother liquor by means of a wash column with forced transport, whose shell of the process chamber is a metal wall, the wash column additionally being enveloped by a thermal insulation material having a water vapor barrier and a specific heat flow of >0.1 W/m2 and
摘要翻译:一种通过强制运输的洗涤柱从母液中的悬浮液中除去丙烯酸,甲基丙烯酸,N-乙烯基吡咯烷酮或对二甲苯晶体的方法,其处理室的外壳是金属壁,洗涤柱 另外由具有水蒸气阻挡层和通过洗涤塔的金属壁流入处理室的> 0.1W / m 2和<10W / m 2的比热流的隔热材料包围。
摘要:
A process for storing a monomer phase which is liquid under the conditions of storage and comprises methacrylic monomers to an extent of ≧95% by weight and has been obtained by condensation out of a gaseous phase or by melting a crystalline phase, in a storage vessel, in which polymer of the monomer present in dissolved form in the liquid monomer phase is removed therefrom on the route from its generation into the storage vessel, and also a process for withdrawing liquid monomer phase from the storage vessel in which polymer of the monomer present in dissolved form in the monomer phase is likewise removed.
摘要:
A process for continuously removing a target product X in the form of fine crystals from a liquid phase P comprising the target product X and constituents other than the target product X by cooling suspension crystallization in an indirect heat transferee, in which the crystal suspension formed is conducted out of the heat transferer first into a mixed buffer tank and, from there, fed to an apparatus for separating the crystal suspension into crystals and liquid phase, and wherein external measures dissipade the oversaturation of the crystal suspension fed to the buffer vessel with target product X.
摘要:
A process for operating a continuous removal of a target product X in the form of fine crystals of a liquid phase P comprising the target product X and constituents other than the target product X by cooling suspension crystallization in the secondary chamber of an indirect heat exchanger to which liquid phase P flows continuously with simultaneous continuous flow through the primary chamber of the indirect heat exchanger with a coolant, and continuous withdrawal of a crystal suspension S having a degree of crystallization Y from the secondary chamber in two operating states I and II, wherein the coolant temperature is lower, the mass flow of liquid phase P is greater and the molar proportion of the constituents other than the target product X in the liquid phase P in operating state II is greater than in operating state I.
摘要:
A process for storing a monomer phase which is liquid under the conditions of storage and comprises methacrylic monomers to an extent of ≧95% by weight and has been obtained by condensation out of a gaseous phase or by melting a crystalline phase, in a storage vessel, in which polymer of the monomer present in dissolved form in the liquid monomer phase is removed therefrom on the route from its generation into the storage vessel, and also a process for withdrawing liquid monomer phase from the storage vessel in which polymer of the monomer present in dissolved form in the monomer phase is likewise removed.