摘要:
Process for preparing isocyanates by reacting the corresponding amines with phos-gene comprising (a) providing at least one amine-comprising feed stream and at least one phosgene-comprising feed stream, (b) mixing the feed streams to form at least one reaction mixture in a mixing zone, (c) reacting the at least one reaction mixture in a reaction zone and (d) working-up the product mixture obtained from (c).
摘要:
The present invention relates to gas phase phosgenation of amines for preparation of isocyanates. In the present invention, phosgene is prepared by reacting chlorine with an excess of carbon monoxide in a gas phase. The obtained phosgene-containing reaction mixture is divided into two streams by a thermal and/or a membrane separating process. The first stream is a low-carbon monoxide stream of no more than 1% by weight of carbon monoxide, based on a total weight of the first stream. The second stream is a carbon monoxide-rich stream of more than 10% by weight of carbon monoxide, based on a total weight of the second stream. The first stream is used as the phosgene-containing reactant stream in the gas phase phosgenation of amines to prepare isocyanates. The second stream can be recycled into the phosgene synthesis.
摘要:
A reactor (1) for preparing phosgene by gas-phase reaction of carbon monoxide and chlorine in the presence of a solid-state catalyst, which is provided in the catalyst tubes (2) of a bundle of catalyst tubes (2) which are arranged parallel to one another in the longitudinal direction of the reactor (1) and are welded at each of their two ends into a tube plate (3), with introduction of the starting materials at the upper end of the catalyst tubes (2) and discharge of the gaseous reaction mixture at the lower end of the catalyst tubes (2), in each case via a cap, and also with introduction and discharge facilities for a liquid heat transfer medium (6) in the intermediate space (4) between the catalyst tubes (2) , where the flow of the heat transfer medium (6) in the space (4) between the catalyst tubes (2) is guided by deflection plates (5), which leave alternating openings (7) free on opposite sides at the interior wall of the reactor, in which openings the deflection plates (5) have cutouts having the shape of a segment of a circle, and the reactor (1) has no tubes in the region of the openings (7), wherein the heat transfer coefficients at the interface between the catalyst tubes (2) and the heat transfer medium (6) are equalized over each reactor cross section by the flow paths of the heat transfer medium (6) in each reactor cross section, in each case measured from the first to last catalyst tube (2) in the flow direction of the heat transfer medium (6), being matched to one another by means of an altered arrangement of the catalyst tubes (2), is proposed.
摘要:
A reactor (1) for preparing phosgene by gas-phase reaction of carbon monoxide and chlorine in the presence of a solid catalyst, which reactor has a bundle of parallel catalyst tubes (2) aligned in the longitudinal direction of the reactor whose ends are fixed in tube plates (3) and have a cap (4) at each end of the reactor (1), and has deflection plates (6) which are aligned perpendicular to the longitudinal direction of the reactor in the intermediate space (5) between the catalyst tubes (2) and leave free passages (7) located alternately opposite one another on the interior wall of the reactor, and in which the catalyst tubes (2) are charged with the solid catalyst, the gaseous reaction mixture is passed from one end of the reactor via one cap (4) through the catalyst tubes (2) and is taken off from the opposite end of the reactor (1) via the second cap (4) and a liquid heat transfer medium is passed through the intermediate space (5) around the catalyst tubes (2), where the reactor (1) has no tubes in the region of the passages (7), is proposed.
摘要:
A reactor (1) for preparing phosgene by gas-phase reaction of carbon monoxide and chlorine in the presence of a solid catalyst, which reactor has a bundle of parallel catalyst tubes (2) aligned in the longitudinal direction of the reactor whose ends are fixed in tube plates (3) and have a cap (4) at each end of the reactor (1), and has deflection plates (6) which are aligned perpendicular to the longitudinal direction of the reactor in the intermediate space (5) between the catalyst tubes (2) and leave free passages (7) located alternately opposite one another on the interior wall of the reactor, and in which the catalyst tubes (2) are charged with the solid catalyst, the gaseous reaction mixture is passed from one end of the reactor via one cap (4) through the catalyst tubes (2) and is taken off from the opposite end of the reactor (1) via the second cap (4) and a liquid heat transfer medium is passed through the intermediate space (5) around the catalyst tubes (2), where the reactor (1) has no tubes in the region of the passages (7), is proposed.
摘要:
A reactor in the form of a cylinder or prism wherein the interior of the reactor is divided by a cylindrical or prismatic gastight housing G which is arranged in the longitudinal direction of the reactor into an inner region having one or more catalytically active zones, in which in each case a packing composed of monoliths stacked on top of one another, next to one another and behind one another and before each catalytically active zone in each case a mixing zone having solid internals are provided, and an outer region B arranged coaxially to the inner region A, wherein the inner region A is insulated from the outer region B of the reactor by means of a microporous high-performance insulation material having a thermal conductivity 1 at temperatures up to 700° C. of less than 0.05 W/m*K is proposed.
摘要翻译:反应器为圆筒或棱柱形式,其中反应器的内部被圆柱形或棱镜气密的外壳G分隔开,该外壳G在反应器的纵向被布置成具有一个或多个催化活性区域的内部区域,其中 在每种情况下,由堆叠在彼此顶部,彼此相邻并且彼此相邻并且在每种情况下的每个催化活性区域之间的整体组成的填料提供有具有实心内部的混合区域,以及与该区域同轴设置的外部区域B 内部区域A,其中内部区域A通过具有小于0.05W / m 2的温度高达700℃的导热率1的微孔高性能绝缘材料与反应器的外部区域B绝缘; 提出K。
摘要:
A process for preparing diisocyanates by gas-phase phosgenation starting out from a feed stream comprising the corresponding diamines and a phosgene-comprising feed stream, in which the feed streams are separately converted into the gas phase and preheated to the reaction temperature of the gas-phase phosgenation, wherein the waste heat from a plant for preparing chlorine by heterogeneously catalyzed oxidation of hydrogen chloride by the Deacon process is utilized for this purpose, is proposed.
摘要:
Process for preparing isocyanates by reacting the corresponding amines with phos-gene comprising (a) providing at least one amine-comprising feed stream and at least one phosgene-comprising feed stream, (b) mixing the feed streams to form at least one reaction mixture in a mixing zone, (c) reacting the at least one reaction mixture in a reaction zone and (d) working-up the product mixture obtained from (c).
摘要:
A reactor (1) for carrying out a reaction between two fluid starting materials (2, 3) over a catalyst bed (4) with premixing of the fluid starting materials (2, 3) before introduction into the catalyst bed within a delay time of less than 150 ms in a mixing-in device (5), wherein the mixing-in device (5) is made up of the following elements which are arranged essentially transverse to the inflow direction of the first fluid starting material stream (2): two or three rows arranged behind one another of tubes (6) which have turbulence generators on the outside and constrict the flow cross section for the first fluid starting material stream (2) to from ½ to 1/10, with the second fluid starting material stream (3) being passed through the interiors of the tubes (6) and injected via openings (7) in the tubes (6) into the first fluid starting material stream (2), and a perforated plate (10) upstream of the tubes (6) and a perforated plate (11) downstream of the tubes (6), is proposed.
摘要:
The invention proposes a reactor (1) having a contact tube bundle (2) through whose space surrounding the contact tubes a heat-exchange medium circuit is passed, with ring lines (3, 4) at both ends of the reactor with jacket apertures (5, 6) for the supply and discharge of a heat-exchange medium by means of a pump via an external heat exchanger, where the heat-exchange medium is fed to the lower ring line (4) and is discharged to the heat exchanger via the upper ring line (3), and with baffle plates (7) which leave a passage cross section alternately in the reactor center and at the reactor edge. The upper (3) and lower (4) ring lines are each divided into an inner (11, 13) and an outer (12, 14) ring line by a cylindrical partition wall (8, 9), and the heat-exchange medium is fed to the outer lower ring line (14), via a region outside the reactor to the inner upper ring line (11), via the jacket apertures (5) of the latter to the region surrounding the contact tubes (2), via the jacket apertures (6) to the inner lower ring line (13) and subsequently via a region outside the reactor to the outer upper ring line (12).