With the declining oil quality and industrial emissions standards becoming critical, the issue to develop ultra-clean fuel is increasingly difficult, and very necessary. Vary the reaction conditions (such as raising the temperature and pressure of the reaction, reducing airspeed, etc.) can achieve the goal of deep hydrodesulfurization process, however, they will result in the loading cost increased, product quality and the amount of processing oil reduced, also the other issues, therefore, the development of new deep hydrodesulfurization catalyst is imperative.

 

Currently, supported catalyst is the most commonly used industrial catalyst for hydrodesulfurization, however, it can’t meet the immediate requirements of deep hydrodesulfurization, because the carrier takes a large proportion which makes the loading active metal limited. Instead, non-supported hydrodesulfurization catalyst consisted almost entirely of the active metal, and having a very intensive activity gives it a bit more deep hydrodesulfurization.

 

Non-supported hydrodesulfurization catalyst means metal catalyst without a carrier, and takes metal as skeleton, usually applied in the forms of metal, and metal mesh, powder, particle, chip and evaporation film ect.. In industrial, the catalytically active metal and aluminum or silicon are often made into alloys, and then dissolving away the aluminum or silicon with the sodium hydroxide solution to form a metal skeleton, by the way, the most commonly used is Raney nickel, the Raney nickel catalyst is widely used hydrogenation.

 

Non-supported hydrodesulfurization catalyst is taking tungsten, molybdenum as the main active ingredient, either alone or in conjunction with, and joint with compounds of nickel, cobalt; its main preparing methods are: hydrothermal synthesis, sol-gel, solid-phase reaction law and co-precipitation method. Tungsten trioxide is raw material of non-supported hydrodesulfurization catalyst, the composition of the active ingredient may be: Ni-W, Co-Ni-W, Ni-Mo-W, Co-Mo-W and so on.