Studies On The Catalyst For Hydrodearomatization Of Diesel Oil

The hydrodearomatization of diesel oil is an important technique in producing clear diesel oil, although zeolite-based noble metal catalyst was provided with better performance of hydrodearomatic and sulfur-resistance, but acidic zeolite have disadvantage in deep cracking resistance, which affects the life of catalyst and become bottleneck in developing deep hydrodearomatization processing in refinery industry. In this paper, we aimed at developing the hydrodearomatization catalyst for the second step of two-stage hydrotreatement technics of diesel oil. By choosing model compound and diesel fuel as feed, the performance of the catalyst obtained from different method and modified techniques has been investigated. The research results indicate that although noble metal catalysts supported on unmodified zeolite HY have the higher performance on aromatic saturation and ring opening, the disadvantage is poor stability which ascribable to deep cracking because of the stronger acidity. Second, different modified processing we have developed can all obtain acidic modification and macrospores develop. Proper concentration fluoride, NaOH solution, vanadium solution, acid solution and high temperature calcinations can reduced acidity and form more macrospore. But the effect of chromium solution and amine modified are not very well. The last, designed catalyst from modified HY support have been investigated by model compound or FCC diesel oil feed hydrogenation test, the result indicate that modified zeolite Y and the performance of loaded noble metal catalyst have better performance in hydrodearomatization and restrain deep cracking activity.