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In this work, a ternary hydrodesulfurization catalyst with fluorine introduced into the FeZn bimetallic active sites was prepared by a step-by-step incipient wetness impregnation. Among them, the sulfur removal ability increases gradually with the addition of F, and then tends to remain constant. Compared with FeZn catalyst, the maximum activity of the fluorinated catalyst can increase to 6 times at 613 K. It is found that the synergy effect exists in the ternary FeZnF species according to the characterization results. As a part of the active phase, not only the acidity of the catalyst was improved and the dispersion of metal species was optimized by F, but also the closed cycle of complex electron transfer among Fe-Zn-F was aggravated resulting in the weaken of Fe-O/Fe-S bond. Therefore, the sulfurization degree of FeZnF(x) was improved which leads to more active sites and noteworthy HDS activity. [Display omitted] • The ternary Fe-Zn-F was obtained by introducing the promoter F into the active sites. • The HDS activity was enhanced and the trend was increased and then remained invariant. • The electron transfer behavior among Fe, Zn and F was important to improve activity. • The acidity and dispersion played an auxiliary role in the amelioration of activity. [ABSTRACT FROM AUTHOR]

Brønsted acid of zeolite Y plays an important role in catalytic cracking reaction. However the proportion of strong Brønsted acid in conventional zeolite Y is small which limits the efficiency of transformation. This work described a way to achieve the goal of significant increasing the density of strong Brønsted acid via introducing Zr4+ into the framework of zeolite Y. The density of strong Brønsted acidity increased from 0.085 (HY) to 0.208 mmol/g ([Zr,Al]-HY). Systematic characterization results showed that the introduction of Zr4+ could produce more Si(1Al) but less Si(3Al) and Si(2Al) species in zeolite which was responsible for the high density of Brønsted acid. And abundant mesopores were also formed during the Zr4+ implanting. For the catalytic cracking results of n-octane, the conversion on [Zr,Al]-HY was 1.67 times of that on conventional HY. The apparent activation energy of cracking n-octane on [Zr,Al]-HY was reduced to 73.3%, which indicated that the increase of strong Brønsted acid had significant effect on catalytic cracking. On the other hand, a large number of mesoporous structures of [Zr,Al]-HY provided a good foundation for the catalytic cracking of steric hindered 1.3.5-triisopropylbenzene (1,3,5-TIPB). [Display omitted] • Zr4+ can promote the produce of relatively isolated Al species. • The density of strong Brønsted acidity increased from 0.085 to 0.208 mmol/g. • The E a of cracking n-octane is reduced to 73.3% (from 120 to 88 kJ/mol). [ABSTRACT FROM AUTHOR]