摘要:
A process for preparing acrolein or acrylic acid or a mixture thereof from propane, in which propane is dehydrogenated under heterogeneous catalysis in a reaction zone A and the propylene formed is partially oxidized heterogeneously in a reaction zone, reaction zone A being operated in loop mode and reaction gas mixture input stream A fed to the reaction zone A comprising added molecular hydrogen which is added to this input stream as late as possible.
摘要:
A process for long-term operation of a continuous heterogeneously catalyzed partial dehydrogenation of a hydrocarbon to be dehydrogenated, in which a reaction gas mixture stream comprising the hydrocarbon to be dehydrogenated in a molar starting amount KW is conducted through an overall catalyst bed comprising the total amount M of dehydrogenation catalyst and the deactivation of the overall catalyst bed is counteracted in such a way that, with increasing operating time, the contribution to the conversion in the first third of the total amount M of dehydrogenation catalyst in flow direction decreases, the contribution to the conversion in the last third of the total amount M of dehydrogenation catalyst in flow direction increases, and the contribution to the conversion in the second third of the total amount M of dehydrogenation catalyst in flow direction passes through a maximum.
摘要:
A process for continuous heterogeneously catalyzed partial dehydrogenation of at least one hydrocarbon to be dehydrogenated in a reactor which is manufactured from a steel with specific elemental composition on its side in contact with the reaction gas, and also partial oxidations of the dehydrogenated hydrocarbon and the reactor itself.
摘要:
A process for continuous heterogeneously catalyzed partial dehydrogenation of at least one hydrocarbon to be dehydrogenated in a reactor which is manufactured from a composite material which consists, on its side in contact with the reaction chamber, of a steel B with specific elemental composition which, on its side facing away from the reaction chamber, either directly or via an intermediate layer of copper, or of nickel, or of copper and nickel, is plated onto a steel A with specific elemental composition, and also partial oxidations of the dehydrogenated hydrocarbon and the reactor itself.
摘要:
A process for stably operating a continuous preparation process for obtaining acrolein or acrylic acid or a mixture thereof from propane, in which the feed rate of fresh propane to the process is utilized as a correcting element for stable steady-state operation.
摘要:
Processes for producing butadiene from n-butane comprising: (a) providing a feed gas stream comprising n-butane; (b) non-oxidatively dehydrogenating the feed gas stream in the presence of a catalyst in a first dehydrogenation zone to form a first intermediate gas stream comprising n-butane, 1-butene, 2-butene, butadiene and hydrogen; (c) oxidatively dehydrogenating the first intermediate gas stream in the presence of an oxygenous gas having an oxygen content of at least 75% by volume in a second dehydrogenation zone to form a second intermediate gas stream comprising n-butane, butadiene, hydrogen, carbon dioxide and steam; (d) compressing and cooling the second intermediate gas to form a first condensate stream comprising water and a third intermediate gas stream comprising n-butane, butadiene, hydrogen, carbon dioxide and steam; (e) compressing and cooling the third intermediate gas to form a second condensate stream comprising n-butane, butadiene and water and a fourth intermediate gas stream comprising n-butane, butadiene, hydrogen and carbon dioxide; (f) cooling the fourth intermediate gas stream to form a third condensate stream comprising n-butane and butadiene, and an offgas stream comprising carbon dioxide and hydrogen; (g) removing water from the second condensate stream and combining the second condensate stream and third condensate stream to form a C4 hydrocarbon stream comprising n-butane and butadiene; and (h) separating the C4 hydrocarbon stream to form a recycle stream comprising n-butane and a product stream comprising butadiene; wherein at least a portion of the recycle stream is fed to the first dehydrogenation zone.
摘要:
A process for preparing butadiene from n-butane, comprising the steps of A) providing a feed gas stream a comprising n-butane; B) feeding the feed gas stream a comprising n-butane into at least one first dehydrogenation zone and nonoxidatively, catalytically dehydrogenating n-butane to obtain a gas stream b comprising n-butane, 1-butene, 2-butene, butadiene and hydrogen, with or without carbon dioxide and with or without steam; C) feeding the gas stream b and an oxygenous gas into at least one second dehydrogenation zone and oxidatively dehydrogenating 1-butene and 2-butene to obtain a gas stream c comprising n-butane, butadiene, hydrogen, carbon dioxide and steam, D) compressing in at least one first compression stage and cooling the gas stream c to obtain at least one condensate stream d1 comprising water and a gas stream d2 comprising n-butane, butadiene, hydrogen, carbon dioxide and steam, E) separating the gas stream d2 by extractive distillation into a product stream e1 consisting substantially of butadiene and a stream e2 comprising n-butane, hydrogen, carbon dioxide and steam, F) compressing in at least one further compression stage and cooling the gas stream e2 to obtain at least one condensate stream f1 comprising n-butane and water, and a gas stream f2 comprising n-butane, hydrogen and carbon dioxide, G) cooling the gas stream f2 to obtain a condensate stream g1 comprising n-butane and an offgas stream g2 comprising carbon dioxide and hydrogen, H) removing water from the at least one condensate stream f1 and, if appropriate, from the condensate stream g1 by phase separation to obtain at least one recycle stream hi comprising n-butane and at least one wastewater stream h2, and recycling the at least one recycle stream h1 into the first dehydrogenation zone.
摘要:
A process for preparing butadiene from n-butane, comprising the steps of A) providing a feed gas stream a comprising n-butane; B) feeding the feed gas stream a comprising n-butane into at least one first dehydrogenation zone and nonoxidatively catalytically dehydrogenating n-butane to obtain a product gas stream b comprising n-butane, 1-butene, 2-butene, butadiene, hydrogen and low-boiling secondary constituents, with or without carbon oxides and with or without steam; C) feeding the product gas stream b of the nonoxidative catalytic dehydrogenation and an oxygenous gas into at least one second dehydrogenation zone and oxidatively dehydrogenating n-butane, 1-butene and 2-butene to obtain a product gas stream c comprising n-butane, 2-butene, butadiene, low-boiling secondary constituents, carbon oxides and steam, said product gas stream c having a higher content of butadiene than product gas stream b; D) removing the low-boiling secondary constituents and steam to obtain a C4 product gas stream d substantially consisting of n-butane, 2-butene and butadiene; E) separating the C4 product gas stream d into a stream e1 consisting substantially of n-butane and 2-butene and a product-of-value stream e2 consisting substantially of butadiene by extractive distillation; F) recycling stream e1 into the first dehydrogenation zone.
摘要翻译:一种从正丁烷制备丁二烯的方法,包括以下步骤:A)提供包含正丁烷的进料气流a; B)将包含正丁烷的进料气流a进料到至少一个第一脱氢区和非氧化催化脱氢的正丁烷中,以获得包含正丁烷,1-丁烯,2-丁烯,丁二烯,氢和 低沸点二次成分,有或没有碳氧化物,有或没有蒸汽; C)将非氧化催化脱氢的产物气流b和氧气输送到至少一个第二脱氢区,并使正丁烷,1-丁烯和2-丁烯氧化脱氢得到包含正丁烷的产物气流c, 丁二烯,低沸点二次成分,碳氧化物和蒸汽,所述产物气流c具有比产物气流b更高的丁二烯含量; D)除去低沸点二次成分和蒸汽,得到基本上由正丁烷,2-丁烯和丁二烯组成的C 4 H 4产物气流d; E)通过萃取蒸馏将C 4 S 4产物气流d分离成基本上由正丁烷和2-丁烯组成的流e 1和基本上由丁二烯组成的价值产物流e 2; F)将流e 1再循环到第一脱氢区。
摘要:
A process for preparing butadiene from n-butane, comprising the steps of A) providing a feed gas stream a comprising n-butane; B) feeding the feed gas stream a comprising n-butane into at least one first dehydrogenation zone and nonoxidatively, catalytically dehydrogenating n-butane to obtain a gas stream b comprising n-butane, 1-butene, 2-butene, butadiene and hydrogen, with or without steam, with or without carbon oxides and with or without inert gases; C) feeding the gas stream b and an oxygenous gas into at least one second dehydrogenation zone and oxidatively dehydrogenating 1-butene and 2-butene to obtain a gas stream c comprising n-butane, butadiene, hydrogen, steam, with or without carbon oxides and with or without inert gases; D) compressing in at least one first compression stage and cooling the gas stream c to obtain at least one condensate stream d1 comprising water and a gas stream d2 comprising n-butane, butadiene, hydrogen and steam, with or without carbon oxides and with or without inert gases; E) separating the gas stream d2 by extractive distillation into a product stream e1 consisting substantially of butadiene and a stream e2 comprising n-butane, hydrogen and steam, with or without carbon oxides and with or without inert gases, F) if appropriate compressing in one or more further compression stages and cooling the gas stream e2 to obtain at least one condensate stream f1 comprising n-butane and water, and a gas stream f2 comprising n-butane and hydrogen, with or without carbon oxides and with or without inert gases, and if appropriate recycling the condensate stream f1 into the first dehydrogenation zone; G) separating the gas stream f2 into a recycle stream g1 comprising n-butane and an offgas stream g2 comprising hydrogen, with or without carbon oxides and with or without inert gases, by contacting the gas stream f2 with a high-boiling absorbent and subsequently desorbing the gas constituents dissolved in the absorbent.
摘要:
A process for regenerating a catalyst bed deactivated in the course of a heterogeneously catalyzed partial dehydrogenation of a hydrocarbon, in which a gas comprising molecular oxygen is conducted at elevated temperature through the deactivated catalyst bed and, in the course of the regeneration, the content of molecular oxygen in the regeneration gas is increased repeatedly and the increase in the carbon oxide content of the regeneration gas as it flows through the deactivated catalyst bed is restricted to values of ≦5% by volume.