Process for the preparation of molybdenum disulfide nanoparticles supported on titania
The invention relates to a process for the preparation of nanoparticles of MoS 2 supported on TiO 2 wherein the preparation is performed by reductive coprecipitation using aqueous solutions containing Ti and Mo precursor salts, and wherein MoS 2 may be non-promoted or Co-promoted. Further, the invention relates to the use of said nanoparticles as hydrodesulfurization catalysts.
1. A two-step hydrolysis process for the preparation of nanoparticles of MoS 2 supported on TiO 2 , wherein the two-step process comprises: preparing a dispersion of blue TiO 2-X support particles by adding a base to an aqueous solution of TiCl 3 and maintaining a resulting mixture under hydrolysis conditions for a time period; keeping said dispersion under an inert atmosphere, and introducing an aqueous solution of thiomolybdate to said dispersion to form said nanoparticles; and recovering said nanoparticles that are polycrystalline rutile and brooktie.
2. A two-step process as recited in claim 1 , wherein said nanoparticles have a specific surface area in the range of from 100 to 130 m 2 /g.
3. A two-step process as recited in claim 1 , wherein the value of X of the formula TiO 2-X is between 0 and 0.3.
4. A two-step process as recited in claim 1 , wherein said thiomolybdate is ammonium tetrathiomolybdate [(NH 4 ) 2 MoS 4 ].
5. A two-step process as recited in claim 1 , wherein said nanoparticles comprise polycrystalline rutile-brookite.
6. A two-step hydrolysis process as recited in claim 1 , wherein said base is sodium hydroxide.
7. A two-step thermolysis process as recited in claim 1 , wherein said aqueous solution of thiomolybdate comprises ammonium tetrathiomolybdate dissolved in citric acid solution and added ammonia.
8. A hydrodesulfurization process, comprising: passing a reaction feed over a hydrodesulfurization catalyst comprising nanoparticles produced by the two-step process of claim 1 .
9. A two-step thermolysis process for the preparation of nanoparticles of MoS 2 supported on TiO 2 , wherein said two-step process comprises:
preparing a dispersion of blue TiO 2-X support particles by maintaining an acidic aqueous solution of TiCl 3 under thermolysis conditions for a time period;
maintaining said dispersion under an inert atmosphere, and introducing an aqueous solution of thiomolybdate to said dispersion to form said nanoparticles; and
recovering said nanoparticles that are crystalline and comprises rutile polymorph.
10. A two-step process as recited in claim 9 , wherein said nanoparticles have a specific surface area in the range of from 100 to 130 m 2 /g.
11. A two-step process as recited in claim 9 , wherein the value of X of the formula TO 2-X is between 0 and 0.3.
12. A two-step process as recited in claim 9 , wherein said thiomolybdate is ammonium tetrathiomolybdate [(NH 4 ) 2 MoS 4 ].
13. A two-step thermolysis process as recited in claim 9 , wherein said acidic aqueous solution of TiCl 3 includes hydrochloric acid.
14. A two-step thermolysis process as recited in claim 9 , wherein said aqueous solution of thiomolybdate comprises ammonium tetrathiomolybdate dissolved in citric acid solution and added ammonia.