我国“缺油少气煤炭相对丰富”的资源特点决定了煤基CO酯化制碳酸二甲酯(DMC)具有重要价值. Pd(II)/NaY已被证明是该反应的有效催化剂, 但由于NaY分子筛的酸性造成原料亚硝酸甲酯部分分解, 因此研发非分子筛体系的催化剂具有重要意义. CeO2是一种常用的氧化物载体, 由于其酸性较弱, 原料亚硝酸甲酯分解问题几乎不存在, 然而Pd/CeO2催化剂的DMC选择性却较低. 为了提升DMC选择性, 本工作在CeO2载体中引入不同比例的Pr, 以期增大CeO2的氧空位浓度, 进而提升DMC选择性. 我们合成了Pd/Pr-CeO2-2.5, Pd/Pr-CeO2-5, Pd/Pr-CeO2-7.5, Pd/Pr-CeO2-10四种不同Pr掺杂比例的催化剂, 发现其DMC选择性显著差异, Pd/Pr-CeO2-5催化剂表现出最佳的DMC选择性(77%). 通过拉曼光谱(Raman)和X-射线光电子能谱(XPS)分析, 结合催化性能, 发现DMC选择性与氧空位浓度成正比关系. 通过氢气程序升温还原(H2-TPR)表征发现, Pd/Pr-CeO2-5催化剂的还原温度最高, 说明具有最高氧空位浓度的Pd/Pr-CeO2-5催化剂, 其金属-载体相互作用也最强, 可以稳定Pd(II)活性物种, 因而表现出最高的DMC选择性. 本工作的研究结果揭示了氧化物载体的氧空位浓度与DMC选择性之间的构-效关系, 对于研发非分子筛体系的高性能DMC催化剂具有重要指导意义.
Xu
,
Meng-Xin
,
Yang
,
Zhi-Jian
,
Sun
,
Jing
,
Zou
,
Wen-Qiang
,
Xu
,
Zhong-Ning
,
Guo
,
Guo-Cong
. Pd/Pr-CeO2催化剂载体氧空位调控CO酯化制碳酸二甲酯选择性[J]. 化学学报, 0
: 0
-A25020035
.
DOI: 10.6023/A25020035
The resource characteristics of "oil-deficient, gas-deficient, and coal is relatively abundant" in China determine that coal-based CO esterification to dimethyl carbonate (DMC) is of great value. Pd(II)/NaY has been proved to be an effective catalyst for this reaction, but because the acidity of NaY molecular sieve causes partial decomposition of the raw material methyl nitrite, it is of great significance to develop non-molecular sieve catalysts. CeO2 is a commonly used oxide support. Because of its weak acidity, the decomposition problem of methyl nitrite is almost non-existent, but the selectivity to DMC over Pd/CeO2 catalyst is low. In order to improve the DMC selectivity, this work introduced different proportions of Pr into CeO2 carrier, in order to increase the oxygen vacancy concentration of CeO2, and then improve DMC selectivity. We synthesized Pd/Pr-CeO2-2.5, Pd/Pr-CeO2-5, Pd/Pr-CeO2-7.5, and Pd/Pr-CeO2-10 catalysts with different Pr doping ratios, and found that their DMC selectivity was significantly different. Pd/Pr-CeO2-5 catalyst showed the best DMC selectivity (77%). To explore the reasons for this difference, we performed a series of characterizations. Plasma emission spectroscopy (ICP) and transmission electron microscopy (TEM) demonstrated the successful doping of Pr into the support. By Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) analysis, combined with catalytic performance, it is found that the selectivity to DMC is proportional to the concentration of oxygen vacancy. Through the characterization of hydrogen programmed temperature reduction (H2-TPR), it was found that the reduction temperature of Pd/Pr-CeO2-5 catalyst is the highest, indicating that Pd/Pr-CeO2-5 catalyst with the highest oxygen vacancy concentration also had the strongest metal-support interaction, which could stabilize Pd(II) active species. Therefore, the highest DMC selectivity is shown. The results of this work reveal the structure-activity relationship between the oxygen vacancy concentration of the oxide support and the selectivity of DMC, which has important guiding significance for the development of high-performance DMC catalysts in non-molecular sieve systems.
[1] Otsuka K; Yagi T; Yamanaka I.Electrochim. Acta. 1994, 39, 2109-2115.
[2] Tundo P.; Selva M.Acc. Chem. Res. 2002, 35, 706-716.
[3] Yadav S.S.; Mali N.A.; Joshi S. S.; Chavan, P.V. J. Chem. Eng. Data.2017, 62, 2436-2442.
[4] Wei H.-M.; Wang, F; Zhang J.-L.; Liao B.; Zhao N.; Xiao F.-K.; Wei W.; Sun, Y.-H. Ind. Eng. Chem. Res.2013, 52, 11463-11478.
[5] Ehinon K. K.D.; Naille, S.; Dedryvère, R.; Lippens, P. E.; Jumas, J. C.; Gonbeau, D.Chem. Mater. 2008, 20, 5388-5398.
[6] Joho, F.; Novák, P.; Electrochim. Acta. 2000, 45, 589-599.
[7] Babad H.; Zeiler A.G. Chem. Rev.1973, 73, 75-91.
[8] Wang H.; Wang M.-H.; Zhang W.-Y.; Zhao N.; Wei W.; Sun Y.-H. Catal. Today.2006, 115, 107-110.
[9] Wu C.-H.; Zhao X.-Q.; Wang Y.-J. Petrochem. Techno.2004, 33, 508-541(in Chinese). (邬长城, 赵新强, 王延吉, 石油化工. 2004, 33, 508-511.)
[10] Bo X.-L.; Xia D.-K.; Qiu T.; Li P. Chem. Intermed.2006, 11, 23-28(in Chinese). (薄向利, 夏代宽, 邱添, 李萍. 化工中间体. 2006, 11, 23-28.)
[11] Delledonne D.; Rivetti F.; Romano, U. Appl. Catal. A-Gen.2001, 221, 241-251.
[12] Matsuzaki T.; Nakamura A.Catal. Surv. from Asia. 1997, 1,77-88.
[13] [13]Ge, Y.-D.; Dong, Y.-Y.; Wang, S.-P.; Zhao, Y.-J.; Lv, J.; Ma, X.-B.; Front. Chem. Sci. 2012, 6, 415-422.
[14] Lv D.-M.; Xu Z.-N.; Peng S.-Y.; Wang Z.-Q.; Chen Q.-S.; Chen Y.; Guo, G.-C. Catal. Sci. Technol.2015, 5, 3333-3339.
[15] Tan H.-Z.; Wang Z.-Q.; Xu Z.-N.; Sun J.; Chen Z.-N.; Chen Q.-S.; Chen Y.; Guo, G.-C. Catal. Sci. Technol.2017, 7, 3785-3790.
[16] Ji S.; Chen Y.; Zhao G.; Wang Y.; Sun W.; Zhang Z.; Lu Y.; Wang, D. Appl. Catal. B: Environ.2022, 304, 120922.
[17] Tan H.-Z.; Chen Z.-N.; Xu Z.-N.; Sun J.; Wang Z.-Q.; Si R.; Zhuang W.; Guo G.-C. ACS Catal.2019, 9, 3595-3603.
[18] Wu S.; Chen J.; Guo R.; Tong H.; Zong S.; Diao Z.; Qin Y.; Yao Y.Chem. Eng. J. 2024, 486.
[19] Hu S.; Xie C.; Xu Y.-P.; Chen X.; Gao M.-L.; Wang H.; Yang W.; Xu Z.-N.; Guo G.-C.; Jiang, H.-L. Angew. Chem. Int. Ed.2023, 62, e202311625.
[20] Han X.; Guo D.; Wang Y.; Huang S.; Wang M.-Y.; Wang Y.; Li M.; Wang S.; Ma X. ACS Catal.2024, 14 (13), 9812-9828.
[21] Wang C.-Z.; Xu N.; Huang K.; Liu B.; Zhang P.; Yang G.; Guo H.; Bai P.; Mintova, S. Chem. Eng. J.2023, 466, 143136.
[22] Wang C.-Z.; Xu W.; Qin Z.; Guo H.; Liu X.; Mintova, S. J. Energy Chem.2021, 52, 191-201.
[23] Jiang H.-B.; Lin S.-J.; Xu Y.-P.; Sun J.; Xu Z.-N.; Guo, G.-C. Acta Chim. Sinica.2022, 80, 438-443(in Chinese). (江辉波, 林淑娟, 徐玉平, 孙径, 徐忠宁, 郭国聪. 化学学报. 2022, 80, 438-443.)
[24] Zhang S.; Xia Z.-M.; Ni T.; Zhang Z.-Y.; Ma Y.-Y.; Qu Y.-Q.J. Catal. 2018, 359, 101-111.
[25] Bai S.-X.; Liu F.-F.; Huang B.-L.; Li F.; Lin H.-P.; Wu T.; Sun, M.-Z; Wu J.-B.; Shao Q.; Xu Y.; Huang X.-Q. Nat. Commun.2020, 11, 954.
[26] Liu J.-X.; Su Y.; Filot I. A.W.; Hensen, E. J. M.J. Am. Chem. Soc. 2018, 140, 4580-4587.
[27] Zhang S.; Chang C.-R.; Huang Z.-Q.; Li J.; Wu Z.; Ma Y.; Zhang Z.; Wang Y.; Qu Y.J. Am. Chem. Soc. 2016, 138, 2629-2637.
[28] Hu C.; Jing K.-Q.; Lin X.-Q.; Sun J.; Xu Z.-N.; Guo G.-C.Catal. Lett. 2022, 152, 503-512.
[29] [29]Li, J.-H.; Liu, Z.-Q.; Cullen, D. A.; Hu, W.-H.; Huang, J.-E.; Yao, L.-B.; Peng, Z.-M.; Liao, P.-L.; Wang, R.-G.; ACS Catal. 2019, 9, 11088-11103.
[30] Kim H. J.; Shin D.; Jeong H.; Jang M. G.; Lee H.; Han, J. W. ACS Catal.2020, 10, 14877-14886.
[31] Ahn K.; Yoo D. S.; Prasad D. H.; Lee H. W.; Chung Y.-C.; Lee J.-H.Chem. Mater. 2012, 24, 4261-4267.
[32] McBride J. R.; Hass K. C.; Poindexter B. D.; Weber, W. H. J. Appl Phys.1994, 76, 2435-2441.
[33] Jiang Z.-Y.; Jing M.-Z.; Feng X.-B.; Xiong J.-C.; He C.; Mark D.; Zheng L.-R.; Song W.-Y.; Liu J.; Qu, Z.-G. Appl. Catal. B Environ.2020, 278, 119304.
[34] Deng Y.-B.; Tian P.-F.; Liu S.-J.; He H.-Q.; Wang Y.; Ouyang L.; Yuan, S.-J. J. Hazard. Mater.2022, 426, 127793.
[35] Xiao Z.-R.; Li Y.-T.; Hou F.; Wu C.; Pan L.; Zou J.-J.; Wang L.; Zhang X.-W.; Liu G.-Z.; Li, G.-Z. Appl. Catal. B Environ.2019. 258, 117940.
