Abstract Pyrolysis of high density polyethylene (HDPE) has been carried out in a conical spouted bed reactor (500 °C) and the volatiles have been reformed in-line over a Ni commercial catalyst in a fluidized bed reactor. The evolution of reaction indices (conversion, H 2 yield and other gaseous product yields) with time on stream has been studied under the following operating conditions: temperature, 600–700 °C; space-time, 8.3–20.8 g cat min g HDPE − 1 , and steam/plastic ratio, 3–5. High initial conversion (> 94.5%) and H 2 yields (> 76.7%) are attained under all the operating conditions studied, with HDPE conversion and H 2 yield increasing when the three variables are increased, which is explained by the enhancement of the reforming reaction. However, a significant effect of operating conditions on catalyst stability has been observed. Thus, an increase in temperature, space-time and steam/plastic ratio decreases catalyst deactivation as a consequence of a lower rate of coke deposition on the catalyst due to both a lower C 5 + coke precursor amount in the reaction medium and a higher gasification rate of the coke deposited.

中文翻译：

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HDPE热解挥发物重整条件对焦炭催化剂失活的影响

摘要 高密度聚乙烯 (HDPE) 的热解在锥形喷射床反应器 (500 °C) 中进行，挥发物已在流化床反应器中通过 Ni 工业催化剂在线重整。已经在以下操作条件下研究了反应指数（转化率、H 2 产率和其他气态产物产率）随时间的变化：温度，600-700 °C；时空，8.3–20.8 g cat min g HDPE − 1 和蒸汽/塑料比，3–5。在所研究的所有操作条件下都实现了高初始转化率 (> 94.5%) 和 H 2 产率 (> 76.7%)，当三个变量增加时，HDPE 转化率和 H 2 产率增加，这可以通过重整的增强来解释反应。然而，已经观察到操作条件对催化剂稳定性的显着影响。