| 摘要 |
<p>Continuous production of polyamide-6 from epsilon -caprolactam (virgin lactam) using oligomers comprising residual lactam, comprises: (a) concentrating the extract water; (b) treating mixture for 3-6 hours, at a pressure of 3-8 bar and a temperature of 225-255[deg] C; (c) treating the mixture obtained from step (b) at 240-265[deg] C and a pressure of 3-8 bar for 8-14 hours until an oligomer proportion of mixture is reduced to not > 1.8 wt.%; (d) mixing the mixture with virgin lactam until an oligomer proportion of mixture of not > 0.7 wt.% is reached; and (e) supplying the mixture to a pre-condensation pipe. Continuous production of polyamide-6 from epsilon -caprolactam (virgin lactam) using oligomers comprising residual lactam from at least one extraction stage, comprises: (a) concentrating the extract water, up to a water proportion of not > 35 wt.%; (b) treating the mixture from the step (a) for 3-6 hours, at a pressure of 3-8 bar and a temperature of 225-255[deg] C; (c) treating the mixture obtained from step (b) at 240-265[deg] C and a pressure of 3-8 bar for a time span of 8-14 hours until an oligomer proportion of the mixture is reduced to not > 1.8 wt.%; (d) mixing the mixture obtained from the step (c) with virgin lactam in at least one further step until an oligomer proportion of the mixture of not > 0.7 wt.% is reached; and (e) supplying the mixture to a pre-condensation pipe to obtain polyamide-6 by polycondensation. An independent claim is also included for a device for implementing the above mentioned method, comprising a precondensation pipe (1) which is preceded in the process direction by a re-polymerization step (2), where the re-polymerization step, in succession in the process direction, has at least one evaporation device (3), at least one first pressure reactor (4) and at least one second pressure reactor (5) and also a mixing device (6) disposed between the second pressure reactor and the precondensation pipe.</p> |
