Abstract:
Mo-, Bi- and Fe-comprising multimetal oxide compositions of the general stoichiometry I, Mo12BiaCobFecKdSieOx (I), where a=0.5 to 1, b=7 to 8.5, c=1.5 to 3.0, d=0 to 0.15, e=0 to 2.5 and x=the stoichiometric coefficient of O2− which guarantees the electric neutrality of the multimetal oxide, and 12−b−1.5·c=A and 0.5≦A≦1.5, 0.2≦a/A≦1.3, and 2.5≦b/c≦9, and the use thereof.
Abstract:
Mo-, Bi- and Fe-comprising multimetal oxide compositions of the general stoichiometry I, Mo12BiaCobFecKdSieOx (I), where a=0.5 to 1, b=7 to 8.5, c=1.5 to 3.0, d=0 to 0.15, e=0 to 2.5 and x=the stoichiometric coefficient of O2− which guarantees the electric neutrality of the multimetal oxide, and 12−b−1.5·c=A and 0.5≦A≦1.5, 0.2≦a/A≦1.3, and 2.5≦b/c≦9, and the use thereof.
Abstract:
A process for mixing a liquid or mixture of a liquid and a fine solid present in a vessel, in which the vessel is supplied with the same liquid or the same mixture as a motive jet of a jet nozzle which is present in the vessel and has a motive jet and a momentum exchange chamber, the suction region between motive nozzle and momentum exchange chamber being provided with a sheath which has a suction orifice below the central jet leading from the motive nozzle into the momentum exchange chamber.
Abstract:
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.
Abstract:
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.
Abstract:
A process for mixing a liquid or mixture of a liquid and a fine solid present in a vessel, in which the vessel is supplied with the same liquid or the same mixture as a motive jet of a jet nozzle which is present in the vessel and has a motive jet and a momentum exchange chamber, the suction region between motive nozzle and momentum exchange chamber being provided with a sheath which has a suction orifice below the central jet leading from the motive nozzle into the momentum exchange chamber.
Abstract:
In process for cleaning tray columns which are used for the purposes of rectifiying liquids comprising (meth)acrylic compounds, a basic liquid is conveyed downward through the tray column and a gas is passed through the column in countercurrent to the basic liquid at an average gas phase differential pressure over all trays of at least 0.5 mbar/tray.
Abstract:
The invention relates to a method for purifying a raw melt of at least one monomer by crystallization, wherein suspension crystallization is initially used and the resulting remaining melt or the suspension crystals that have been molten once again and separated are subjected to a mechanical separation operation before undergoing subsequent purification by crystallization.
Abstract:
A process for covering the demand for polymers I in a country I, in which the monomers of the polymer I are obtained in at least one country II, then these monomers are polymerized free-radically to polymer I in this country II, and polymer I thus obtained is subsequently exported to a country I.
Abstract:
A chimney tray for a column for thermal treatment of a liquid. The chimney tray includes a total take-off of liquid by a drain connection arranged at an edge of the chimney tray, and having one or more drain channels having a gradient in a direction of the drain connection, and having a gradient in a direction of the one or more drain channels.