As the demand for gasoline and diesel in transportation fuels increases day by day, engine exhaust emissions are increasingly polluting the environment, and countries around the world have strict restrictions on the quality of fuel products, especially sulfur content. In addition, there are also strict restrictions on the content of benzene, aromatics, olefins, the amount of oxygen-containing compounds added to gasoline, and the cetane number and aromatic content of diesel.

The production of these clean fuels is closely related to the development of hydrogenation technology. Hydrogenation technology mainly includes the development of catalysts and process technology. Hydrogenation refining can effectively hydrogenate organic compounds of impurity elements such as sulfur, nitrogen and oxygen contained in oil products. For diesel refining after secondary processing, it also includes selective hydrogenation saturation of olefins, diolefins, aromatics and polycyclic aromatics, and removal of impurities such as metals. It has the advantages of a wide range of raw materials, high liquid yield and good product quality. The hydrogenation raw materials used in industrial processes mainly include light alkanes, gasoline, kerosene, petroleum waxes, lubricating oils, vacuum light diesel oils and atmospheric and vacuum residues. Due to the differences in raw material structure and composition, some hydrorefining processes can directly produce qualified products and obtain motor fuels that meet specification requirements, such as gasoline, kerosene and diesel fraction hydrorefining; while some can only provide high-quality feed for downstream processes, such as reforming pre-hydrogenation, hydrocracking one-stage refining and residue hydrotreating. Hydrorefining catalysts are made by impregnating active metal components into carriers. Its active components are generally transition metal elements and their compounds, including Mo and W in the VB group and Co, Ni, Fe, Pd and Pt in the VIII group. These metals have the conditions to be active components in terms of electronic properties and geometric properties.At present, the hydrorefining catalyst commonly used in industry is composed of Mo or W sulfide as the main catalyst and Co or Ni sulfide as the co-catalyst. When these metals exist alone, their catalytic activity is not high, but when they exist at the same time, they cooperate with each other and have high catalytic activity. Therefore, most hydrorefining catalysts are composed of a binary active component composed of a VB group metal and a Ⅷ group metal.

In recent years, the research on hydrorefining catalysts has focused more on the unification of material science and catalyst manufacturing technology, so as to adjust the acidity, shape selectivity, porosity, specific surface area and strength of the catalyst. The research contents mainly include:

(1) Focus on the selection of carriers, including the addition of additives and the improvement of preparation methods. According to the different processed oil products, the carrier is required to have a suitable pore structure and specific surface area and an external structure that is conducive to the diffusion control of hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) reactions;

(2) Discussion on catalyst preparation technology. Seek a catalyst production method with simple process, low cost, less pollution, and an ideal metal surface and good dispersion after increasing the active component loading within a certain range, and good bonding between the active metal and the carrier. After appropriate adjustment, the catalyst has strong adaptability and has the characteristics of a wide range of oil processing, large material processing capacity, low energy consumption, good thermal stability and high mechanical strength.