| Dimethyl carbonate (DMC) is an environmentally benign building block; the research and development of clean technology to synthesize DMC by liquid-phase oxidative carbonylation of methanol are attracted more and more attention from the world. In this paper, the synthesis of Dimethyl Carbonate is studied and the catalysts were prepared by solid-state ion-exchange method, which will be theoretical importance and practical value.In this thesis, a series of Cu1 catalysts supported on the zeolite were prepared by solid-state ion exchange. The catalytic activity to synthesize DMC was studied in a batch and continuous stainless autoclave equipment. The catalysts have been characterized by the SEM, BET, IR, XRD and XPS analytical methods and well discussed; the catalytic processes have also been researched fundamentally. The conclusions obtained are listed as following:(1) In batch reaction process, prepared at 250℃ ~350℃for 4h HZSM-5-CuCl catalyst is better than DASY-CuCl, but 450℃~650℃ for 4h DASY-CuCl catalyst is better than HZSM-5-CuCl. When prepared at 350℃ for 4h , the HZSM-5-CuCl catalyst has the maximum of STY of DMC, 0.56 g.g·-1·h-1. When prepared at 450℃ for 4h, the DASY-CuCl catalyst has the maximum of STY and selectivity of DMC, 0.52 g·g-1·h-1 and 97.67% respectively.(2) In continuous reaction process, the STY of DMC of Hβ-CuCl catalysts is higher than that of HZSM-5-CuCl catalysts, but the selectivity of DMC of H|3-CuCl catalysts is higher than that of HZSM-5-CuCl catalysts. When prepared at 350℃ for 4h, the HZSM-5-CuCl catalyst has the maxima for STY and selectivity of DMC, 0.51g·g-1·h-1 and 92.39%0 respectively. When prepared at 550℃ for 4h, the Hβ-CuCl catalyst has the maxima for STY and selectivity of DMC, 0.55 g·g-1·h-1 and 80.39% respectively.(3) STY and selectivity of DMC reach the highest points when batch system was conducted at the reaction temperature of 140℃ for 2h under a pressure of 3.0 MPa and CO/O2 ratio of 2. STY and selectivity of DMC reach the maximum when continuous system is conducted at the reaction temperature of 120℃ for 3h under pressure of 4.5MPa and CO/O2 ratio of 2.(4) STY and selectivity of DMC at batch system for HZSM-5-CuCl catalyst prepared at 350℃for 4h are 0.44 g·g-1·h-1 and 90.85%, and are superior than at continuoussystem.(5) Catalysts supported on the used three kinds of zeolite prepared by solid state ion exchang have reactivity for synthesis of DMC by liquid-phase oxidative carbonylation of methanol. The active sequence is Hβ-CuCl >HZSM-5-CuCl > DASY-CuCl and it decrease with the ratio of SiO2/Al2O3 increasing when using the same kind of zeolite.(6) Fresh catalysts have a little crystalline phase of CuCl, the used catalysts are no more crystalline phase of CuCl and but new phase of CuCl2-3Cu(OH)2 was observed by XRD.(7) The crystalline phase of CuCl in the catalyst reduce remarkably with preparing temperature and time increasing. Catalyst prepared at 550℃for 4h has a bit crystalline phase of CuCl, Catalyst prepared at 650 ℃ for 4h has no crystalline phase of CuCl. The framework structure of H|3 zeolite was destroyed gradually with preparing temperature and time increasing.(8) Cu and Cl were distributed homogeneously in the zeolite for Hp-CuCl catalyst prepared at 650℃for lOh. But distribution of Cu and Cl was uneven after reaction.(9) The specific surface area of used catalyst decrease due to clustering. The specific surface area of catalyst decrease with preparing temperature increasing.(10) Cu species in catalyst surface had four states: CuCl2 CuO, CuCl2, Cu(OH)2. CuCl is maximum for the freshcatalyst. CuO, CuCl2, Cu(OH)2 was formed and CuCl was lost for used catalyst.(11) The morphological analysis by SEM> XPS> XRD and IR shows used catalysts have clustering phenomena and form new phase of hydroxide formation (CuCl2-3Cu(OH)2).
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