摘要:
A process is described for removing hydrogen cyanide from mixtures comprising pentenenitrile, wherein the removal is effected by an azeotropic distillation of hydrogen cyanide with 1,3-butadiene.
摘要:
A process is described for removing hydrogen cyanide from mixtures comprising pentenenitrile, wherein the removal is effected by an azeotropic distillation of hydrogen cyanide with 1,3-butadiene.
摘要:
A method for producing 3-pentenenitrile is provided that includes: (a) isomerizing an educt stream containing 2-methyl-3-butenenitrile on at least one dissolved or dispersed isomerisation catalyst to form a stream (1), which contains the isomerisation catalyst(s), 2-methyl-3-butenenitrile, 3-pentenenitrile and (Z)-2-methyl-2-butenenitrile; (b) distilling the stream (1) to obtain a stream (2) as the overhead product, which contains 2-methyl-3-butenenitrile, 3-pentenenitrile and (Z)-2-methyl-2-butenenitrile and a stream (3) as the bottom product, which contains the isomerisation catalyst(s); (c) distilling the stream (2) to obtain a stream (4) as the overhead product, which is enriched with (Z)-2-methyl-2-butenenitrile in comparison to stream (2), and a stream (5) as the bottom product, which is enriched with 3-pentenenitrile and 2-methyl-3-butenenitrile in comparison to stream (2); (d) distilling stream (5) to obtain a stream (6) as the bottom product, which contains 3-pentenenitrile and a stream (7) as the head product containing 2-methyl-3-butenenitrile.
摘要:
A process is described for separating mixtures of isomeric pentenenitriles, in which at least one isomer is removed from the mixture, wherein the separation of the substance mixtures of isomeric pentenenitriles is effected distillatively under reduced pressure.
摘要:
A process is described for continuously hydrocyanating 1,3-butadiene in the presence of at least one nickel(0) catalyst with chelate ligands, wherein 1,3-butadiene and hydrogen cyanide are used in a molar ratio of from 1.6:1 to 1.1:1.
摘要:
A process is described for preparing 3-pentenenitrile by hydrocyanating 1,3-butadiene in the presence of at least one catalyst, wherein the reaction is carried out in a loop reactor having external pumped circulation and jet nozzle for driving the internal circulation.
摘要:
A process is described for preparing 3-pentenenitrile by hydrocyanating 1,3-butadiene in the presence of at least one catalyst, wherein unhydrocyanated 1,3-butadiene is removed from the effluent of the hydrocyanation and recycled into the process, and the recycled 1,3-butadiene is monitored for the content of hydrogen cyanide.
摘要:
A process is described for isomerizing pentenenitrile in a reactant stream, wherein the isomerization is effected over a heterogeneous catalyst in a distillation column in such a way that, during the isomerization of the isomerization reactant, it is distillatively depleted in relation to the isomerization product in the reaction column of the distillation column.
摘要:
A process for the recovery of a Lewis acid from a reaction mixture (I) which has been obtained in the hydrocyanation of an olefinically unsaturated compound to a nitrile which has a miscibility gap with water under certain pressure and temperature conditions, in the presence of a catalyst system comprising a Lewis acid and a complex compound. The method comprises a) removing the complex compound from mixture (I) to give a mixture (II), b) adding water to mixture (II) and placing mixture (II) under pressure and temperature conditions to provide a phase (III) and a phase (IV), c) adding a liquid diluent (V) which c1) does not form an azeotrope with water and whose boiling point under certain pressure conditions is higher than that of water, or c2) forms an azeotrope or heteroazeotrope with water under certain pressure conditions, to phase (III), d) subjecting the mixture of phase (III) and liquid diluent (V) to distillation under the pressure conditions mentioned in step c1) or c2), and e) subjecting mixture (VII) to hydrocyanation of an olefinically unsaturated compound to give the nitrile
摘要:
A method for producing 3-pentenenitrile is provided that includes: (a) isomerizing an educt stream containing 2-methyl-3-butenenitrile on at least one dissolved or dispersed isomerization catalyst to form a stream (1), which contains the isomerization catalyst(s), 2-methyl-3-butenenitrile, 3-pentenenitrile and (Z)-2-methyl-2-butenenitrile; (b) distilling the stream (1) to obtain a stream (2) as the overhead product, which contains 2-methyl-3-butenenitrile, 3-pentenenitrile and (Z)-2-methyl-2-butenenitrile and a stream (3) as the bottom product, which contains the isomerization catalyst(s); (c) distilling the stream (2) to obtain a stream (4) as the overhead product, which is enriched with (Z)-2-methyl-2-butenenitrile in comparison to stream (2), and a stream (5) as the bottom product, which is enriched with 3-pentenenitrile and 2-methyl-3-butenenitrile in comparison to stream (2); (d) distilling stream (5) to obtain a stream (6) as the bottom product, which contains 3-pentenenitrile and a stream (7) as the head product containing 2-methyl-3-butenenitrile.