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Hydroisomerization catalysts Pt/ZSM-22,Pt/ZSM-23,and Pt/ZSM-22/ZSM-23 were prepared by supporting Pt on ZSM-22,ZSM-23,and intergrowth zeolite ZSM-22/ZSM-23,respectively.The typical physicochemical properties of these catalysts were characterized by X-Ray Diffraction(XRD),N2 absorption-desorption,Pyridine-Fourier Transform Infrared(Py-FTIR),Transmission Electron Microscopy(TEM),X-Ray Fluorescence(XRF),Scanning Electron Microscopy(SEM) and NH3-Temperature Programmed Desorption(NH3-TPD),and the performance of these catalysts in n-dodecane hydroisomerization was evaluated in a continuous down-flow fixed bed with a stainless steel tubular reactor.The characterization results indicated that the intergrowth zeolite ZSM-22/ZSM-23 possessed the dual structure of ZSM-22 and ZSM-23,and the catalyst Pt/ZSM-22/ZSM-23 had similar pores and weak acidity to Pt/ZSM-22 and Pt/ZSM-23 catalysts.Moreover,Pt/ZSM-22/ZSM-23 catalyst showed a high selectivity in hydroisomerization of long chain n-alkanes to mono-branched isomers.The evaluation results for n-dodecane hydroisomerization indicated that the activity of Pt/ZSM-22/ZSM-23 was the lowest,while the hydroisomerization selectivity was the highest among the three catalysts.The maximum yield of i-dodecane product was 68.3% over Pt/ZSM-22/ZSM-23 at 320 oC.
23, and Pt / ZSM-22 were prepared by supporting Pt on ZSM-22, ZSM-23, and intergrowth zeolite ZSM-22 / ZSM- The typical physicochemical properties of these catalysts were characterized by X-ray Diffraction (XRD), N2 absorption-desorption, Pyridine-Fourier Transform Infrared (Py-FTIR), Transmission Electron Microscopy (TEM), X-Ray Fluorescence Scanning Electron Microscopy (SEM) and NH3-Temperature Programmed Desorption (NH3-TPD), and the performance of these catalysts in n-dodecane hydroisomerization was evaluated as a continuous down-flow fixed bed with a stainless steel tubular reactor. The characterization results indicated that the intergrowth zeolite ZSM-22 / ZSM-23 possessed the dual structure of ZSM-22 and ZSM-23, and the catalyst Pt / ZSM- 22 / ZSM- 23 had similar pores and weak acidity to Pt / ZSM- 22 and Pt / ZSM-23 catalysts.Moreover, Pt / ZSM-22 / ZSM-23 catalyst showed a high selectivity in hydroisomerization of long chain n-alkanes to mo no-branched isomers. The evaluation results for n-dodecane hydroisomerization indicates that the activity of Pt / ZSM-22 / ZSM-23 was the lowest, while the hydroisomerization selectivity was the highest among the three catalysts. The maximum yield of i-dodecane product was 68.3% over Pt / ZSM-22 / ZSM-23 at 320 oC.