119-42-6Relevant articles and documents
Influence of nanoscale distribution of Pd particles in the mesopores of MCM-41 on the catalytic performance of Pd/MCM-41
Dong, Chao,Li, Xiang,Wang, Anjie,Chen, Yongying,Liu, Haiou
, p. 219 - 222 (2017)
Two different nanoscale Pd particle distributions in MCM-41, i.e. in the mesopores and on the external surface, were obtained by using a siliceous MCM-41 and a silylated MCM-41 (S-MCM-41) as the starting support materials, respectively. The electron density of Pd in Pd/S-MCM-41 was lower than that in Pd/MCM-41. Pd/S-MCM-41 exhibited much better selective hydrogenation performance but a lower hydrogenolysis activity than Pd/MCM-41. These differences are related to the different Pd particle distributions in MCM-41 and S-MCM-41, demonstrating that the performance of noble metal catalysts is tunable by simply controlling the nanoscale metal particle distribution in the pores.
Effective hydrodeoxygenation of dibenzofuran by a bimetallic catalyst in water
Dong, Peng,Lu, Guo-Ping,Cai, Chun
, p. 1605 - 1609 (2016)
Effective hydrodeoxygenation (HDO) of dibenzofuran (DBF) catalyzed by a bimetallic nickel/platinum (Ni/Pt) catalyst in water was demonstrated at 200 °C and 1.2 MPa hydrogen (H2) pressure. The bimetallic catalysts prepared by a wet chemical method exhibit prominent activity that overcomes the limitations of use of a single Ni or Pt metal catalyst. The yield of HDO products can be up to 90%. Reaction results indicate that the conversion of DBF was affected by the reaction temperature and H2 pressure. The deoxygenation selectivity was strongly dependent on reaction temperature. The reaction pathway is also proposed.
Cu/Mg/Al/Zr non-noble metal catalysts for o-phenylphenol synthesis
Zeng, Yongping,Zhang, Tianchi,Xu, Yueyang,Hu, Peili,Ye, Ting,Jia, Zhehua,Ju, Shengui
, p. 6737 - 6746 (2016)
Cu/Mg/Al/Zr hydrotalcite-like precursors with Zr4+:(Al3+ + Zr4+) atomic ratios between 0 and 1 were prepared by co-precipitation methods. The precursors were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric (TG) analysis and Fourier transform infrared spectroscopy (FT-IR). The results confirmed that well-defined layered double hydroxides (LDH) can be synthesized when the added Zr content is less than 0.25 in terms of Zr4+/(Al3+ + Zr4+) atomic ratio. The catalysts of Cu/Zn/Al/Zr mixed oxides can be obtained via thermal decomposition of hydroxide precursors, and can be used in dehydrogenation of 2-(1-cyclohexenyl) cyclohexanone (CHCH) to ortho-phenylphenol (OPP). Copper particles inside the catalyst act as active sites for dehydrogenation. Transmission electron microscopy (TEM), XRD, N2O chemisorption and N2 adsorption-desorption were performed to investigate the effect of Zr content on determining the copper particle size. Based on the catalytic performance test, it was concluded that the conversion of CHCH depends on the copper particle size of these catalysts.
ALKYLATION OF PHENOL WITH CYCLOHEXENE.
Seino,Okazaki,Saito
, p. 32 - 38,32,33,34,37 (1976)
The alkylation of phenol with cyclohexene in the vapor phase has been studied over the cation-exchanged X zeolite catalysts. Because of the dealkylation of products, the catalytic activity decreased with rising reaction temperature. The yield of cyclohexy
Nanocrystalline hierarchical ZSM-5: An efficient catalyst for the alkylation of phenol with cyclohexene
Radhika,Selvin, Rosilda,Kakkar, Rita,Roselin, L. Selva
, p. 5404 - 5413 (2018/02/28)
In this paper, authors report the synthesis of nanocrystalline hierarchical zeolite ZSM-5 and its application as a heterogeneous catalyst in the alkylation of phenol with cyclohexene. The catalyst was synthesized by vacuum-concentration coupled hydrothermal technique in the presence of two templates. This synthetic route could successfully introduce pores of higher hierarchy in the zeolite ZSM-5 structure. Hierarchical ZSM-5 could catalyse effectively the industrially important reaction of cyclohexene with phenol. We ascribe the high efficiency of the catalyst to its conducive structural features such as nanoscale size, high surface area, presence of hierarchy of pores and existence of Lewis sites along with Br?nsted acid sites. The effect of various reaction parameters like duration, catalyst amount, reactant mole ratio and temperature were assessed. Under optimum reaction conditions, the catalyst showed up to 65% selectivity towards the major product, cyclohexyl phenyl ether. There was no discernible decline in percent conversion or selectivity even when the catalyst was re-used for up to four runs. Kinetic studies were done through regression analysis and a mechanistic route based on LHHW model was suggested.
