【摘要】 采用均匀共沉淀法制备Ni/CaO-SiO₂固体碱催化剂,选择2-（2-甲氧基苯氧基）-1-苯基乙醇作为典型β-O-4木质素模型化合物进行催化剂性能评价。考察了不同Ni、CaO质量分数的Ni/CaO-SiO₂催化剂对β-O-4氢解转化反应的催化活性,探究其对β-O-4产物分布的影响。结果表明:Ni在β-O-4催化转化反应中起主导作用,Ni质量分数的增加有利于β-O-4的催化转化;不同质量分数的Ni、CaO均会对β-O-4的转化产物分布造成一定影响,随着Ni质量分数的增加,β-O-4转化产物种类增加,而CaO的添加会影响1-苯基乙醇的生成。考察不同载体的催化剂对β-O-4催化转化产物分布的影响,并结合XPS表征发现:其产物分布变化主要由Ni与CaO的相互作用引起,与载体无关。在此基础上,提出了Ni/SiO₂与Ni/CaO-SiO₂催化裂解β-O-4中C—O醚键可能的反应路径。更多还原

【Abstract】 Ni/CaO-SiO₂ solid base catalyst was prepared by deposition-precipitation（DP） method. 2-（2-Methoxyphenoxy）-1-phenylethanol was used as a typical β-O-4 lignin model compound for catalyst performance evaluation. Catalytic activities of Ni/CaO-SiO₂ catalysts with different mass fractions of Ni and CaO were investigated. In addition, their effects on the product distributions of β-O-4 hydrolysis were also investigated. Experimental results show that Ni plays a dominant role in the catalytic conversion of β-O-4, and high Ni mass fraction is beneficial to the catalytic conversion of β-O-4. Product distribution of β-O-4 hydrolysis is also affected by the mass ratio of Ni and CaO. As mass ratio of Ni increases, more β-O-4 hydrolysis products can be found; while CaO addition can affect the formation of 1-phenylethanol. It is also found that the interaction between Ni and CaO can significantly impact on hydrolysis product distribution, but carriers have very little impact on product distribution. In addition, the possible pathways of β-O-4 conversion over Ni/SiO₂ and Ni/CaO-SiO₂ were proposed.更多还原