Synthesis of NiW Supported on an Al-Modified Cubic Ia3d Mesoporous KIT-5 Catalyst and Its Hydrodenitrogenation Performance of Quinoline

Xing Liu,Zhenrong Li,Liangfu Zhao,Haitao Cui,Shaoqing Guo,Lijing Yuan,Xin Li,Hongyu Dong

doi:10.3390/catal10101183

Abstract

Pure KIT-5 and a series of Al-KT-X materials modified by different amounts of aluminum were synthesized by a direct hydrothermal method and acted as supports for the catalysts of a quinoline hydrodenitrification reaction with the NiW active phases supported. The results of X-ray diffraction (XRD), N2 isotherm absorption-desorption, scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) for the supports indicated that Al species were embedded into the framework of the KIT-5 materials with a large pore size, pore volume, and specific surface area. The Pyridine-Fourier transform infrared spectroscopy (Py-IR) result of the catalysts demonstrated that the addition of aluminum atoms enhanced the acidity of the catalysts. The results of the high-resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectra (XPS) characterizations for the sulfide catalysts indicated that the embedded Al species could facilitate the dispersion of active metals and the formation of the active phases. Among all the catalysts, NiW/Al-KT-40 showed the maximal hydrodenitrogenation conversion (HDNC) due to its open three-dimensional pore structure, appropriate acidity, and good dispersion of active metals.

Highlights

With the world’s light oil reserves decreasing, the conversion of unconventional oil products, such as coal tar and heavy oil, into clean fuel oil has received increasing attention from researchers.The hydrofining of coal tar to produce light fuel oil is of great practical and strategic significance to replace certain petroleum resources
The results show that the modified NiW/Al-KT-X catalysts had a higher sulfidation degree than the NiW/KIT-5 catalyst because the introduction of aluminum species regulates the interaction between supports and active metals and, enhances the dispersion of active metals [16]
All supports and catalysts were characterized by X-ray diffraction (XRD), N2 isotherm absorption–desorption, Fourier transform infrared (FTIR), Pyridine-Fourier transform infrared spectroscopy (Py-IR), and scanning electron microscopy (SEM), and the series of sulfide catalysts were characterized by high-resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectra (XPS)

Summary

Introduction

The hydrofining of coal tar to produce light fuel oil is of great practical and strategic significance to replace certain petroleum resources. The presence of nitrogen compounds in car tar produces NOx pollutants during the combustion process, and deactivates the catalysts of the hydrocracking or hydrorefining process. Nitrogen compounds in car tar must be removed by hydrodenitrogenation (HDN) reaction, and developing efficient hydrogenation catalysts is one of the key technologies for the HDN of coal tar [4,5,6,7,8,9]. Scientists have made many attempts to prepare high performance catalysts, including the application of different active phases and various supports. NiW, as the active phase of catalysts, has excellent catalytic activity on the Catalysts 2020, 10, 1183; doi:10.3390/catal10101183 www.mdpi.com/journal/catalysts

Methods

Results

Conclusion