Thermal cracking of HDPE has been investigated in a two-step process. The primary pyrolysis takes place in the first reactor while the second reactor allows vapor phase secondary reactions to take place. The effect of residence time (RT) and temperature in the secondary reactor on the liquid product (LP) profile has been elucidated. The change in RT does not significantly alter the B.P. distribution of the LP; however, an increase in the RT leads to a reduction in the total olefinic content but with a simultaneous increase in the percentage of lower olefins (C6-C8). An increase in temperature from 350 to 450ºC results in the shifting of carbon number distribution to lower values along with an increase in total olefinic content. Thus the second reactor conditions, in a two-step process, plays a major in controlling the LP profile and a suitable choice of the same can help in obtaining desirable products.

中文翻译：

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聚烯烃的热解分两步进行：二级反应的作用

HDPE的热裂化已通过两步过程进行了研究。初级热解在第一反应器中发生，而第二反应器允许气相次级反应发生。已经阐明了停留时间（RT）和二级反应器中的温度对液体产物（LP）分布的影响。RT的变化不会显着改变LP的BP分布；然而，RT的增加会导致总烯烃含量的降低，但同时低级烯烃（C6-C8）的百分比也会增加。温度从350升高到450ºC会导致碳数分布向更低的值移动，同时总烯烃含量也会增加。因此，在两步过程中，第二个反应器条件