Abstract In this work, in-situ and ex-situ catalytic pyrolysis (CP) of sawdust by Ni-based and Cu-based catalysts are compared in a two-stage fixed bed reactor. Alkali metal K and alkaline earth metal Mg are used to modify the catalysts for comparison. The ex-situ configuration plays a more dominant role in reducing tar while increasing gas production for all catalysts. Reduced Ni shows the best catalytic activity for hydrogen production, obtaining 36.4 vol.% of hydrogen with a yield of 13.6 mmol/g-bio in ex-situ CP. With the increase of temperature, ex-situ CP has a more significant effect on improving gas product and reducing liquid product than in-situ CP. K presents better modification effect than Mg, resulting in a higher yield of gaseous products. Also, TG and Raman analysis indicate that K can decrease the amount of coke deposition on catalysts and make the coke easier to be removed.

中文翻译：

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木屑原位催化热解与异位催化热解产气比较

摘要 在这项工作中，在两级固定床反应器中比较了 Ni 基和 Cu 基催化剂对锯末的原位和异位催化热解 (CP)。使用碱金属 K 和碱土金属 Mg 对催化剂进行改性以进行比较。非原位配置在减少焦油同时增加所有催化剂的气体产量方面起着更重要的作用。还原的 Ni 显示出最佳的制氢催化活性，在异位 CP 中获得 36.4 vol.% 的氢气，产率为 13.6 mmol/g-bio。随着温度的升高，异位CP比原位CP对提高气体产品和减少液体产品的作用更显着。K 比 Mg 具有更好的改性效果，导致气态产物的产率更高。还，