کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
59909 | 1419449 | 2013 | 10 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Catalytic conversion of methyl chloride to lower olefins over modified H-ZSM-34 Catalytic conversion of methyl chloride to lower olefins over modified H-ZSM-34](/preview/png/59909.png)
Among several typical zeolites, H-ZSM-34 was found to be an efficient catalyst for the conversion of methyl chloride to lower olefins, i.e., ethylene, propylene, and butenes. Treatment of H-ZSM-34 with a Na2H2EDTA (EDTA = ethylenediaminetetraacetate) aqueous solution followed by ion exchange and calcination enhanced the catalytic performance significantly. The selectivity to lower olefins increased significantly for certain Na2H2EDTA aqueous solution concentrations; when the H-ZSM-34 catalyst was treated with a 0.1 mol/L Na2H2EDTA solution, the selectivity and yield of C2–C4 olefins reached 82% and 61%, respectively, at 673 K and a CH3Cl partial pressure of 9.2 kPa. The modification of H-ZSM-34 with Ce ions improved C2–C4 olefin selectivity and yield. Catalyst characterization suggests that treatment with Na2H2EDTA or modification by Ce decreases the acidity of H-ZSM-34. The weakened acidity of the treated or modified H-ZSM-34 may suppress the hydrogen transfer reaction and prevent lower olefins from further transformation to paraffins.
H-ZSM-34 was an efficient catalyst for the conversion of methyl chloride to lower olefins. The treatment of H-ZSM-34 with Na2H2EDTA or modification with Ce further enhanced the lower olefin yield to 60%–61%.Figure optionsDownload as PowerPoint slide
Journal: Chinese Journal of Catalysis - Volume 34, Issue 11, November 2013, Pages 2047–2056