钾盐催化纤维素快速热裂解机理研究

Catalysis mechanism of potassium salt during rapid pyrolysis of cellulose

在红外辐射机理试验装置上进行了钾盐催化纤维素快速热裂解机理研究。试验发现,钾盐在抑制生物油生成的同时,促进了炭和气体的生成。结合反应前后金属盐电镜图以及生物油和焦炭中金属离子质量分数的检测,证实钾盐的催化作用主要发生在固相中,以离子形式选择性催化了不同类别的反应,加速了分子断键过程中的裂变和歧化反应。在抑制左旋葡聚糖生成的同时,促进了糖类以外产物的形成,提高了生物油中乙醇醛、乙醛以及小分子的醇类、酮醛类化合物的数量。

The catalysis mechanism of potassium salt in rapid pyrolysis of cellulose was studied in an infrared radiation bench scale reactor. The results show that potassium salt restrains the formation of aqueous oil, while enhances the formation of char and gas. On the basis of the distribution diagram of metallic salt by electron microscopy, and the content determination of metallic ion in aqueous oil and char, catalysis of potassium salt mainly occurs in solid phase during cellulose pyrolysis. It selectively catalyzes some reactions in the form of ion, and accelerates the cracking and splitting process of molecules. It causes a reduction of levoglucosan formation, and improves the production of hydroxyacetaldehyde, acetaldehyde and small molecule components including methanol, ketone or aldehyde.