Abstract:
The present invention relates to an improved process for batchwise or continuous isomerization of cis-2-pentenenitrile to 3-pentenenitriles in the presence of 1,4-diazabicyclo[2.2.2]octane as catalyst.
Abstract:
A process is described for preparing purified caprolactam, comprising the steps a) extraction of crude caprolactam, obtained from the Beckmann rearrangement of cyclohexanone oxime, with an organic extractant, b) removal of the organic phase from step a), c) distillative separation of the organic extractant from the organic phase from step b) giving rise to water-containing lactam extract, being preceded by addition of the distillative separation, aqueous alkali metal hydroxide solution in an amount of from 0 to 10 mmol/kg of caprolactam, d) addition of 0 to 30 mmol of alkali metal hydroxide/kg of caprolactam to the water-containing lactam extract from step c), e) distillative removal of water from the water-containing lactam extract treated with alkali metal hydroxide from step d), f) freeing the caprolactam from step e) from by-products lower- and higher-boiling than caprolactam by distillation, with addition in steps c) and d) together of at least 1.5 mmol of alkali metal hydroxide/kg of caprolactam.
Abstract translation:描述了制备纯化的己内酰胺的方法,其包括以下步骤:a)从有机萃取剂中提取由Beckmann重排环己酮肟得到的粗己内酰胺,b)从步骤a)中除去有机相,c)蒸馏分离 来自步骤b)的来自有机相的有机萃取剂产生含水内酰胺提取物,之前加入蒸馏分离,碱金属氢氧化物水溶液的量为0至10mmol / kg己内酰胺,d) 向来自步骤c)的含水内酰胺提取物中加入0至30mmol碱金属氢氧化物/ kg己内酰胺,e)从碱金属氢氧化物处理的含水内酰胺提取物中蒸馏除去水,步骤d),f )通过蒸馏将己内酰胺从步骤e)中脱除副产物比己内酰胺更低沸点和更高沸点,在步骤c)和d)中加入至少1.5mmol碱金属氢氧化物/ k g己内酰胺。
Abstract:
A process for the continuous preparation of adiponitrile by hydrocyanation of 3-pentenenitrile is described, wherein a) 3-pentenenitrile is hydrocyanated to give a reaction output comprising adiponitrile, b) in a work-up 1, a mixture comprising cis-2-methyl-2-butenenitrile and cis-2-pentenenitrile is separated off as overhead product from the reaction output from the reactor R1 in a first distillation apparatus, c) the mixture comprising cis-2-methyl-2-butenenitrile and cis-2-pentenenitrile from step b) is continuously isomerized in the presence of aluminum oxide as catalyst in a reactor R2 to give a product mixture comprising 3-pentenenitrile, d) cis-2-methyl-2-butenenitrile is separated off as overhead product from the reaction output from the reactor R2 in a distillation apparatus in a work-up 2 and discharged.
Abstract:
A process is described for preparing purified caprolactam, comprising the steps a) extraction of crude caprolactam, obtained from the Beckmann rearrangement of cyclohexanone oxime, with an organic extractant, b) removal of the organic phase from step a), c) distillative separation of the organic extractant from the organic phase from step b) giving rise to water-containing lactam extract, being preceded by addition of the distillative separation, aqueous alkali metal hydroxide solution in an amount of from 0 to 10 mmol/kg of caprolactam, d) addition of 0 to 30 mmol of alkali metal hydroxide/kg of caprolactam to the water-containing lactam extract from step c), e) distillative removal of water from the water-containing lactam extract treated with alkali metal hydroxide from step d), f) freeing the caprolactam from step e) from by-products lower- and higher-boiling than caprolactam by distillation, with addition in steps c) and d) together of at least 1.5 mmol of alkali metal hydroxide/kg of caprolactam.
Abstract translation:描述了制备纯化的己内酰胺的方法,其包括以下步骤:a)从有机萃取剂中提取由Beckmann重排环己酮肟得到的粗己内酰胺,b)从步骤a)中除去有机相,c)蒸馏分离 来自步骤b)的来自有机相的有机萃取剂产生含水内酰胺提取物,之前加入蒸馏分离,碱金属氢氧化物水溶液的量为0至10mmol / kg己内酰胺,d) 向来自步骤c)的含水内酰胺提取物中加入0至30mmol碱金属氢氧化物/ kg己内酰胺,e)从碱金属氢氧化物处理的含水内酰胺提取物中蒸馏除去水,步骤d),f )通过蒸馏将己内酰胺从步骤e)中脱除副产物比己内酰胺更低沸点和更高沸点,在步骤c)和d)中加入至少1.5mmol碱金属氢氧化物/ k g己内酰胺。
Abstract:
The present invention relates to an improved process for batchwise or continuous isomerization of cis-2-pentenenitrile to 3-pentenenitriles in the presence of 1,4-diazabicyclo[2.2.2]octane as catalyst.
Abstract:
Aspects of the present invention relate to an improved process for exchanging alkali metal or alkaline earth metal ions in zeolites for ammonium ions. For this exchange, aqueous solutions of ammonium salts, for example ammonium sulfate, ammonium nitrate or ammonium chloride, are currently being used. The resulting “ammonium zeolites” are calcined to convert them, with release of ammonia, to the H form of the zeolites suitable as a catalyst. Certain methods provided herein use ammonium carbonate instead of the ammonium compounds mentioned. As excess ammonium carbonate, in contrast to the nitrates, sulfates or chlorides, can be recycled in the form of carbon dioxide and ammonia, the amount of salt which has to be discharged is lowered significantly.