层化法制备MoS2催化剂及其加氢脱氧性能研究

Preparation and Catalytic Properties of Exfoliation MoS2 Catalyst for Hydrodeoxygenation of p-Cresol

摘要:

以商品MoS2为原料，采用正丁基锂嵌入层化法制备出了比表面积明显增大的MoS2催化剂。BET、XRD、SEM等表征结果表明，采用加入阳离子表面活性十六烷基三甲基溴化铵（CTAB）的改进层化法，能够制备出堆叠层数较少的MoS2催化剂，而阴离子表面活性剂的加入不能促进层化效果。MoS2催化对甲基苯酚加氢脱氧反应（HDO）的主要产物为4-甲基环己烯、甲基环己烷和甲苯。层化MoS2催化剂中具有两个催化作用的活性位，即“侧边” 位（Edge）和“棱边”位（Rim），加氢脱氧反应容易发生在“棱边”位上。层化MoS2催化剂中加入助剂Ni或Co可以提高催化剂的加氢脱氧活性，助剂Ni的引入可以促进甲苯转化为甲基环己烷，更有利于提高以生物油为原料所制备燃料油的品质。总体上，加入Ni或Co的层化MoS2催化剂，其HDO反应活性仍不高，可能是由于MoS2本身所具有的特定结构和化学活性的有限性而决定的。

Abstract:

Using commercial MoS2 as raw material, the exfoliated MoS2 catalyst with a large specific surface area was prepared by adopting n-butyl lithium embedded into the MoS2 crystals. BET, XRD, SEM characterization results showed that the improved preparation method via adding cationic surfactant CTAB into the exfoliation process could reduce the height of the stack layers of MoS2, whereas for the adding of anionic surfactant, the exfoliation effect could not be promoted. The main products for the hydrodeoxygenation of p-cresol by MoS2 catalyst were 4-methylcyclohexene, methylcyclohexane and toluene. The exfoliated MoS2 catalyst had two catalysis activated sites which located at the “Edge” and the “Rim” of the layers of the crstals and [基金项目：国家自然科学基金(No. 21306159, 21376202) *联系作者:杨运泉(1963-)，男，教授，博导,Tel：[phone]，E-mail：[e-mail] 作者简介: 杨司军(1990-), 男, 湖南省怀化市人, 硕士研究生, 主要从事催化过程及催化新材料研究。 Tel: [phone], E-mail:[e-mail]]the HDO reaction was much easier to occur at the "Edge". Adding Ni or Co into the exfoliation MoS2 catalyst could improve the activity of HDO and the introduction of Ni could promote the toluene converting into methylcyclohexane, implying that the addition of Ni into the exfoliation MoS2 is more beneficial to the improvement of the fuel oil quality origined from bio-oil raw material. However, the HDO reaction activity of the exfoliated MoS2 was not yet high enough with the addition of Ni or Co into the catalyst, this may be ascribed to the limitation of the specific structure and the chemical activity of MoS2.