Mai Fuhang, Cui Kai, Wen Zhe, Wu Kai, Yan Fei, Chen Mengmeng, Chen Hong, Li Yongdan
State Key Laboratory of Chemical Engineering (Tianjin University), Tianjin Key Laboratory of Applied Catalysis Science and Technology, School of Chemical Engineering, Tianjin University Tianjin 300072 China.
Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin 300072 China.
RSC Adv. 2019 Jan 21;9(5):2764-2771. doi: 10.1039/c8ra07962e. eCollection 2019 Jan 18.
The conversion of guaiacol is examined at 300 °C in supercritical ethanol over a HWO catalyst. Guaiacol is consumed completely, meanwhile, 16.7% aromatic ethers and 80.0% alkylphenols are obtained. Interestingly, -butylphenols are produced mainly with a high selectivity of 71.8%, and the overall selectivity of 2,6-di--butylphenol and 2,6-di--butyl-4-ethylphenol is as high as 63.7%. The experimental results indicate that catechol and 2-ethoxyphenol are the intermediates. Meanwhile, the WO sites play an important role in the conversion of guaiacol and the Brønsted acid sites on HWO enhance the conversion and favour a high selectivity of the -butylphenols. The recycling tests show that the carbon deposition on the catalyst surface, the dehydration and partial reduction of the catalyst itself are responsible for the decay of the HWO catalyst. Finally, the possible reaction pathways proposed involve the transetherification process and the alkylation process during guaiacol conversion.
在300℃下，在超临界乙醇中，以HWO催化剂研究愈创木酚的转化。愈创木酚被完全消耗，同时，得到了16.7%的芳香醚和80.0%的烷基酚。有趣的是，主要生成了选择性高达71.8%的叔丁基酚，2,6-二叔丁基酚和2,6-二叔丁基-4-乙基酚的总选择性高达63.7%。实验结果表明，邻苯二酚和2-乙氧基苯酚是中间体。同时，WO位点在愈创木酚的转化中起重要作用，HWO上的布朗斯特酸位点提高了转化率，并有利于叔丁基酚的高选择性。循环试验表明，催化剂表面的积碳、催化剂本身的脱水和部分还原是HWO催化剂失活的原因。最后，提出的可能反应途径包括愈创木酚转化过程中的转醚化过程和烷基化过程。
