Mingyuan He

Exploratory study on upgrading 1-butene using spent FCC catalyst/additive under simulated conditions of FCCU’s stripper

A novel method for upgrading n-butene into more useful propylene, iso-butene, iso-butane even gasoline using spent fluid catalytic cracking (FCC) catalysts/additives in the stripper part of fluid catalytic cracking unit (FCCU) has been proposed. The simulative tests were carried out on a widely used MAT equipment, using 1-butene as feed. High temperature and low space velocity favor the formation of propylene, iso-butene and iso-butane. The presence of MFI additives promotes propylene and iso-butene but suppresses iso-butane formation.

Active Site Accessibility of Resid Cracking Catalysts

It is well understood that pore structure is important in designing FCC catalysts. For residue cracking, the pore structure of catalyst matrix should be accessible for precracking the large hydrocarbon molecules so that the resulting smaller molecules can transfer into the zeolite channels and can be converted to value-added products over the zeolite sites. However, pore parameters such as pore volume and pore size distribution are insufficient for selecting an appropriate matrix. A method for testing the active site accessibility of resid cracking catalysts has been developed on currently widely used MAT equipped with the unstripped hydrocarbon burned off in place, with an online measurement of the CO2 and H2O that are produced. The effect of pore distribution of the FCC catalyst matrix on the active site accessibility of several catalysts has been tested tentatively in terms of bottoms conversion and strippable coke yield. The results showed that the yields of HCO and strippable coke increase when the matrix small pores increase, and decrease when the catalyst matrixes are highly accessible. These test observations are in agreement with commercial results.

Metal-modified MFI zeolite for enhancing propylene selectivity in FCC process

In this work, we investigate the effect of metal-modified MFI structure zeolite on propylene production, and discuss the mechanism of its enhancing propylene selectivity. The Metal-modified MFI zeolite samples were characterized by HRTEM, EDS, and XPS.

Templateless synthesis of catalysts with narrow mesoporous distribution

In this study, amorphous silica-alumina nanomaterials with narrow mesoporous distribution can be obtained by two novel sol-gel processes, without the use of any templates. the results of our experiments show that the preparation method has a great influence on the precursor sol structure as well as the specific surface area and mesopore volume of the final product, but has no effect on the pore size distribution.

The role of manganese contained zeolite catalysts in tuning bi-/mono-molecular reaction pathway selectivity in FCC process

Abstract The gasoline quality of FCC process, especially olefin content, heavily depends on the catalyst performance in terms of bi-/mono-molecular reaction pathway selectivity. A reliable experimental protocol has been established by using m-xylene as a probe molecule to clarify the selectivity based on detailed reaction chemistry of m-xylene including the consecutive bi-molecular disproportionation and isomerization. Another pure hydrocarbon, n-dodecane, has been used as probe molecule to characterize the selective hydrogen transfer ability of catalytic materials. A novel series of FCC catalysts has been developed aiming at gasoline olefin reduction based on manganese incorporation or modification. The role of manganese in tuning bi/mono-molecular reaction pathway selectivity and hydrogen transfer selectivity in FCC process is elucidated by experimental approaches described. The results have been correlated with the practical performance of the new catalysts.