Abstract: The effects of chelating ligands (nitrilotriacetic acid (NTA), 1,2-ethylenediamine (EN), citric acid (CA), glutamic acid, ethylene-diaminetetraacetic acid (EDTA) or trans-1,2-cyclohexanediamine-N,N,?,?-tetraacetic acid (CyDTA)) during the preparation of CoMo/Al2O3, CoMo/SiO2, NiMo/ SiO2 et al. were reviewed, however, the influence of chelating agent for hydrodesulfurization of catalyst over molecular sieve carrier no reports. In this paper, a new type of EDTA-NiMo/nano-HZSM-5 catalyst for FCC gasoline hydrodesulfurizaiton was prepared. The catalyst showed higher HDS activity and more stable HDS activity for FCC gasoline than the NiMo/nano-HZM-5 catalyst. And they were characterized by XRD, ICP, FT-IR, 27Al NMR, TG-DTA, PyIR, and NH3-TPD. The results indicated that there was a strong interaction between EDTA and nano-HZSM-5, which weakens the interaction between the active metal components and support, improves dispersion of active metal components on the surpport surface. Besides, it is the interantion between EDTA and Ni that promotes the reduction and sulfidation of catalyst. Therefore, the hydrodesulfurization activity of the catalyst is improved.

Key words: Ethylenediamine tetraacetic acid (EDTA), nickel, molybdenum, nano-HZSM-5 zeolite, Hydrodesulfurization (HDS)