The high price brought by the dwindling oil resources has provided an excellent opportunity for coal chemical industry. Coal tar hydrodesulfurization catalyst is facing several difficulties in this stage:
Firstly, the high oxygen content, the water produced in the deoxygenation process is not conducive to the catalyst activity, stability and strength;
Secondly, high content of gum and residual carbon which results in deactivation of the catalyst and reactor fouled;
Thirdly, high content of sulfur and nitrogen in coal tar; Fourthly, coal tar contains a lot of aromatic hydrocarbons which can’t be removed deeply, and therefore a suitable acidic of catalyst is required.

 

The low temperature coal tar hydrodesulfurization catalyst containing with tungsten trioxide which has the suitable acidic is prepared as follows:

1. Preparation of carrier: Uniformly mix the quasi-boehmite, bentonite, H3 molecular sieves and BF3, add the binder (5%~10% the weight of boehmite) and extrusion aid (2%~5% the total weight of the mixture), then distilled water is added, kneading 30~60min, molding to obtain a molded carrier; drying the carrier at 15~60°C for 4~6 hours, at 100°C for 8~I0 hours; raising the temperature to 450~650°C at the rate of 2~5°C/min to roast for 4~6 hours, then we obtain a finished carrier.

2. Preparation of catalyst: Add tungstate, nickel and molybdenum salts respectively into the distilled water, stir under the temperature of 15~60°C until the solid completely dissolved; followed by the addition of phosphoric acid of 3%~6% by weight percentage concentration with stirring continued for 0.5~1 hour to get the impregnating liquid, wherein the weight percent concentrations of tungstate, nickel and molybdenum salt are respectively 15%~20%, 16%~21%, and 10%~18%; the carrier is impregnated into the impregnating solution and taken out after 3~5 hours, dried at 15~60°C for 2~6 hours, at 100°C for 2~6 hours; raising the temperature to 450~550°C at the rate of 2~5°C/min to roast for 4~6 hours to obtain a low-temperature coal tar refined hydrodesulfurization catalyst which contains tungsten trioxide.