摘要:
In a chemical reactor for heterogeneously catalysed reaction of a fluid, comprising a holding device for catalyst particles and/or inert particles (80, 100) through which the fluid flows, the side of the holding device lying upstream when viewed in the direction of flow of the fluid comprises knitted wire mesh fabric (50), and the average clear mesh width of the knitted wire fabric (50) is smaller than the average particle size x50.3 of the particles (80, 100). The invention furthermore relates to a process for reaction of a fluid, wherein the reaction is carried out in a reactor according to the invention in the presence of heterogeneous catalyst particles (80) and the catalyst particles (80) are arranged in the holding device for catalyst particles (80). The invention also provides the use of knitted wire mesh fabric (50) as a holding device for catalyst particles and/or inert particles (80, 100) in chemical reactors.
摘要:
The present invention relates to a process for restoring the activity of spent catalysts for the hydrogenation of aromatic nitro compounds, in which a regeneration comprising at least a first burning off stage, a first washing stage, a second burning off stage and a second washing stage is carried out at periodic intervals.
摘要:
In a chemical reactor for heterogeneously catalyzed reaction of a fluid, comprising a holding device for catalyst particles and/or inert particles (80, 100) through which the fluid flows, the side of the holding device lying upstream when viewed in the direction of flow of the fluid comprises knitted wire mesh fabric (50), and the average clear mesh width of the knitted wire fabric (50) is smaller than the average particle size x50.3 of the particles (80, 100). The invention furthermore relates to a process for reaction of a fluid, wherein the reaction is carried out in a reactor according to the invention in the presence of heterogeneous catalyst particles (80) and the catalyst particles (80) are arranged in the holding device for catalyst particles (80). The invention also provides the use of knitted wire mesh fabric (50) as a holding device for catalyst particles and/or inert particles (80, 100) in chemical reactors.
摘要:
The invention relates to a process for the continuous preparation of aromatic amines by hydrogenation of the corresponding nitroaromatics in the presence of catalysts arranged in reaction spaces, in which an adiabatically operated reaction space RA is connected downstream of an isothermally operated reaction space RI and RA additionally also has a separate feed for the nitroaromatic to be hydrogenated, RI is fed with the nitroaromatic to be hydrogenated from the start to the end of the hydrogenation, and the product mixture emerging from RI is fed into RA from the start to the end of the hydrogenation, wherein RA can additionally be fed via the separate feed with the nitroaromatic to be hydrogenated.
摘要:
The present invention relates to a catalyst comprising a ceramic support with a BET surface area of less than 40 m2/g and (a) 1.0 to 100 g of at least one metal of groups 8 to 12 of the periodic table of the elements, (b) 1.0 g to 100 g of at least one metal of groups 4 to 6 and 12 of the periodic table of the elements and (c) 1.0 g to 100 g of at least one metal of groups 14 and 15 of the periodic table of the elements per liter of bulk volume of the ceramic support, wherein the catalyst is additionally doped with (d) potassium in a content of from 0.0050% by weight to 0.20% by weight, based on the total weight of the catalyst. The present invention also provides the use of such a catalyst in the catalytic gas phase hydrogenation of nitroaromatics.
摘要:
The invention relates to a process for the continuous preparation of aromatic amines by hydrogenation of the corresponding nitroaromatics in the presence of catalysts arranged in reaction spaces, in which an adiabatically operated reaction space RA is connected downstream of an isothermally operated reaction space RI and RA additionally also has a separate feed for the nitroaromatic to be hydrogenated, RI is fed with the nitroaromatic to be hydrogenated from the start to the end of the hydrogenation, and the product mixture emerging from RI is fed into RA from the start to the end of the hydrogenation, wherein RA can additionally be fed via the separate feed with the nitroaromatic to be hydrogenated.
摘要:
The present invention relates to a catalyst comprising a ceramic support with a BET surface area of less than 40 m2/g and (a) 1.0 to 100 g of at least one metal of groups 8 to 12 of the periodic table of the elements, (b) 1.0 g to 100 g of at least one metal of groups 4 to 6 and 12 of the periodic table of the elements and (c) 1.0 g to 100 g of at least one metal of groups 14 and 15 of the periodic table of the elements per litre of bulk volume of the ceramic support, wherein the catalyst is additionally doped with (d) potassium in a content of from 0.0050% by weight to 0.20% by weight, based on the total weight of the catalyst. The present invention also provides the use of such a catalyst in the catalytic gas phase hydrogenation of nitroaromatics.
摘要:
The invention relates to a method for producing nitrobenzene, in which crude nitrobenzene is first produced by nitrating benzene and said crude nitrobenzene is then washed in succession in at least one acid wash, in at least one alkaline wash and in at least one neutral wash, at least one additional wash with an aqueous solution of a potassium salt being interposed between the last alkaline wash and the first neutral wash.
摘要:
The present invention relates to a continuous process for the production of nitrobenzene by nitration of benzene with nitric acid or mixtures of nitric acid and sulfuric acid to give a crude nitrobenzene, washing of the crude nitrobenzene by means of at least one of each of an acid, alkaline and neutral washing, there being obtained a pre-purified nitrobenzene which, as well as containing nitrobenzene, at least contains also low boilers, optionally middle boilers as well as high boilers and salts, wherein the pre-purified nitrobenzene is purified further by separating off low boilers in a distillation apparatus by evaporation of the low boilers, and separation of nitrobenzene from the resulting further purified nitrobenzene in a distillation apparatus by partial evaporation of nitrobenzene, wherein pure nitrobenzene is removed from the distillation apparatus in gaseous form and is subsequently condensed, and wherein the non-evaporated portion of the further purified nitrobenzene is fed back into the washing at any desired point.
摘要:
The invention relates to a method for producing nitrobenzene, in which crude nitrobenzene is first produced by nitrating benzene and said crude nitrobenzene is then washed in succession in at least one acid wash, in at least one alkaline wash and in at least one neutral wash, at least one additional wash with an aqueous solution of a potassium salt being interposed between the last alkaline wash and the first neutral wash.