A nanocellulose template strategy for the controllable synthesis of tungsten-containing mesoporous silica for ultra-deep oxidative desulfurization

- W-containing mesoporous catalysts were prepared using renewable nanocellulose as a template.
- The pore size of the catalysts can be efficiently tuned from 2 nm to 10 nm.
- The catalyst exhibits excellent catalytic activity on the removal of BT, DBT and 4,6-DMDBT.
- The desulfurization process was conducted at mild reaction conditions without any organic solvents.
- The catalysts simultaneously act as both a catalyst and adsorbent.

Nanocellulose is a sustainable and ecofriendly nanomaterial derived from renewable biomass. Herein, we developed a novel controllable method for the synthesis of tungsten-containing mesoporous silica catalysts by using nanocellulose templates. Disordered worm-like mesoporous catalysts with a high dispersion of tungsten species were obtained by this method. In particular, the as-prepared catalysts presented high specific surface areas (344-535 m2/g), and their pore sizes could be efficiently tuned from 2 nm to 10 nm by adjusting the amount of bio-template in the synthesis system. The resultant samples were used as a catalyst for oxidative desulfurization (ODS) without any organic solvents as an extractant. The results showed that the catalysts with a large pore size (10 nm) and an optimal Si/W mol ratio (20) exhibited high catalytic activity, and dibenzothiophene could be completely removed at 60 °C in 10 min. The catalytic activity on different sulfur compounds increased in the order of benzothiophene < 4,6-dimethyldibenzothiophene < dibenzothiophene. GC-MS analysis of the oxidation products revealed that the catalysts simultaneously acted as both a catalyst and an adsorbent. Moreover, after recycling for five times, the removal of the oxidation desulfurization system could still reach 94%. As this method is sustainable, facile and controllable, the as-prepared catalysts could have potential for practical applications.