The effects of magnesium of Zn–Mg–Al additives on catalytic cracking of VGO and in situ reduction of sulfur in gasoline

Abstract

The scope of the present study is to describe the cracking behavior of hydrocarbons and the reduction of sulfur in gasoline in fluid catalytic cracking (FCC) process using Zn-Mg-Al additives with varying the Mg/Al molar ratios. Experiments have been carried out on a microactivity-test (MAT) reactor using high-sulfur vacuum gas oil (VGO) feed and zinc impregnated Mg-Al spinels as additive and the commercial cracking catalyst. It was found that Zn-Mg-Al additives exhibited enhanced Lewis acidity compared with the corresponding Zn-free Mg-Al spinels. The MAT results indicated that the addition of additives reduced the yields of liquid petroleum gas and coke at low Mg contents but increased the coke yield at high Mg contents. Overall, the additives improved the yields of gasoline and diesel. It has also been shown that the rich Lewis acidity had a positive effect on the conversion of aromatic sulfur species of gasoline and the maximum reduction of gasoline sulfur was achieved with Zn/ Mg 4.0 Al 2 O 3 due to the synergistic effect of basicity and Lewis acidity.

Effect of Content of Cerium Ion on Brönsted‐Acid‐Catalyzed Reaction of Thiophene over CeY Zeolite Studied by In Situ FTIR Spectroscopy

“…In addition, HDS is difficulty in removing aromatic sulfur molecules, such as dibenzothiophene (DBT) and 4,6‐dimethyldibenzothiophene (4,6‐DMDBT) . For making up the disadvantages of HDS technique, some non‐hydrodesulfurization techniques ( e. g. in situ sulfur removal, reactive adsorption desulfurization, oxidative desulfurization (ODS), alkylation desulfurization and selective adsorption desulfurization (SADS) are being developed as auxiliary methods. Among these technologies, SADS process is regarded as a promising “zero‐sulfur” technology owing to its mild conditions, good desulfurization performance, low cost, and minimal octane loss .…”