Catalytic performance of Cu- and Zr-modified beta zeolite catalysts in the methylation of 2-methylnaphthalene

Abstract

2,6-Dimethylnaphthalene (2,6-DMN) is a commercially important chemical for the production of polyethylenenaphthalate and polybutylene naphthalate. However, its complex synthesis procedure and high production cost significantly reduce the use of 2,6-DMN. In this study, the synthesis of 2,6-DMN was investigated with methylation of 2-methylnaphthalene (2-MN) over metal-loaded beta zeolite catalysts including beta zeolite, Cu-impregnated beta zeolite and Zr-impregnated beta zeolite. The experiments were performed in a fixed-bed reactor at atmospheric pressure under a nitrogen atmosphere. The reactor was operated at a temperature range of 400-500°C and varying weight hourly space velocity between 1 and 3 h -1 . The results demonstrated that 2,6-DMN can be synthesized by methylation of 2-MN over beta type zeolite catalysts. Besides 2,6-DMN, the product stream also contained other DMN isomers such as 2,7-DMN, 1,3-DMN, 1,2-DMN and 2,3-DMN. The activity and selectivity of beta zeolite catalyst were remarkably enhanced by Zr impregnation, whereas Cu modification of beta zeolite catalyst had an insignificant effect on its selectivity. The highest conversion of 2-MN reached 81%, the highest ratio of 2,6-DMN/2,7-DMN reached 2.6 and the highest selectivity of 2,6-DMN was found to be 20% by using Zr-modified beta zeolite catalyst.

Effectiveness of biogenic waste‐derived heterogeneous catalysts and feedstock hybridization techniques in biodiesel production

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“…The development of polymer nanocomposites has produced a new class of materials with superior mechanical, thermal, and transport properties . These properties depend on several factors, such as the polymer synthesis method, the mixing process, and the nanoreinforcement . In this regard, Cordero et al .…”

“…11,12 The development of polymer nanocomposites has produced a new class of materials with superior mechanical, 13 thermal, 14 and transport properties. 15 These properties depend on several factors, such as the polymer synthesis method, 16,17 the mixing process, 18 and the nanoreinforcement. 13 In this regard, Cordero et al 19 found that the incorporation of a small amount of nanocellulose obtained by hydrolysis can have a substantial improvement of the mechanical properties of polyurethane foams (PUFs) synthesized from castor oil.…”

Effect of β‐nucleating agent and zeolite molecular sieves on supercritical CO2‐assisted cell and crystal nucleation during the long‐chain‐branched polypropylene foaming

“…Therefore, besides the β‐NA, it is necessary to add one of crystallization synergists such as nano‐CaCO 3 and molecular sieve to enhance the percentage of β‐crystals and the toughening and strengthening performance, which are favorable for the foaming process. Molecular sieve is a hydrated aluminosilicate with screening molecular action, which has a regular pore structure as well as catalytic and adsorption effects …”