Ma Ying, Feng Lu, Guo Zhanglong, Deng Jiangtao, Pham-Huu Cuong, Liu Yuefeng
Dalian National Laboratory for Clean Energy (DNL), Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China.
University of Chinese Academy of Sciences, Beijing, China.
Front Chem. 2019 Nov 13;7:751. doi: 10.3389/fchem.2019.00751. eCollection 2019.
The chemoselective hydrogenation of cinnamaldehyde (CAL) to the corresponding hydrocinamaldehyde (HCAL) is a type of important reactions in fine chemistry, which is critically dependent on the rational design the chemical structure of active metal. In this work, calcium promoted palladium on CNT hybrid (Ca-Pd@CNT) with monolithic structure was synthesized through one-pot alginate gel process. The catalytic performance results showed that moderate Ca promotion catalyst (Ca-Pd@CNT) present a superior CAL hydrogenation activity with CAL conversion of 99.9% and HCAL selectivity of 86.4% even at the lager Pd nanoparticle size (c.a. 5 nm). The characterization results show that the electron transfer between the additive Ca promoter and Pd nanoparticles (NPs) could modify the electron structure of Pd species and induce the formation of the partial positively charged Pd species on the Pd NPs surface in the Ca-Pd@CNT catalyst resulting to the satisfactory catalytic performance. Furthermore, the one-pot gel synthesis methodology for microscopic carbon supported catalyst could also endows its great potential industry application in heterogeneous catalysis with easily handling during the transportation and reaction, and attributed to reducing the overall pressure drop across in the fix-bed reactor.
肉桂醛（CAL）化学选择性加氢制备相应的氢化肉桂醛（HCAL）是精细化学领域中的一类重要反应，这严重依赖于活性金属化学结构的合理设计。在本工作中，通过一锅法海藻酸钠凝胶工艺合成了具有整体结构的钙促进的碳纳米管负载钯（Ca-Pd@CNT）。催化性能结果表明，即使在较大的钯纳米颗粒尺寸（约5 nm）下，适度钙促进的催化剂（Ca-Pd@CNT）仍具有优异的CAL加氢活性，CAL转化率为99.9%，HCAL选择性为86.4%。表征结果表明，添加剂钙促进剂与钯纳米颗粒（NPs）之间的电子转移可以改变钯物种的电子结构，并诱导在Ca-Pd@CNT催化剂的钯NPs表面形成部分带正电的钯物种，从而产生令人满意的催化性能。此外，用于微观碳负载催化剂的一锅法凝胶合成方法还赋予了其在多相催化中巨大的潜在工业应用价值，在运输和反应过程中易于处理，并且有助于降低固定床反应器中的整体压降。
