Synthesis, Characterization, and Catalytic Performance of Aminomethylphosphonic Molybdenum Catalysts for Slurry-Phase Hydrocracking

Abstract

R-Aminomethylphosphonic acid (R = diethyl and bis(2-ethylhexyl), denoted as DEAPA and 2EAPA, respectively) was applied as ligands to synthesize a series of aminomethylphosphonic molybdenum precursors (DEAPA-Mo, 2EAPA-Mo, and 2EAPA-2Mo) under moderate conditions. Single-crystal X-ray diffraction, X-ray photoelectron spectroscopy, infrared and Raman spectroscopy, scanning electron microscopy, and high-resolution transmission electron microscopy techniques were employed to analyze the samples before and after sulfidation. The samples were applied as catalyst precursors for slurry-phase hydrocracking of Karamay atmospheric residue. The effects of organic ligand chain length and Mo/P molar ratio on catalytic performance were investigated. The results indicate that 2EAPA-Mo exhibits 1.61 wt % coke formation and 85.5 wt % liquid yields. As a catalyst precursor, 2EAPA-Mo disperses well in the feed oil and upon in situ sulfidation facilitates the formation of a MoS2 phase that is highly active. The superior perfor...