Jianghua Qiu

Effect of oxidised mesoporous carbon containing silver nanoparticle on selectivity of adsorption desulphurisation

Abstract This paper presents the experimental investigation of the effects of nitric acid oxidation and silver loaded modification of coal tar pitch based mesoporous carbons (MCs) on adsorption capacity of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT). The structural and textural properties of the samples were characterised by means of X-ray diffraction, scanning electron microscopy, Boehm titration and nitrogen adsorption–desorption techniques. The results show that after oxidative modification, the average pore sizes of MCs were not changed. It is also found that the specific surface area decreased, while the mesopore ratio, the density of the surface oxygen containing groups increased remarkably. Furthermore, silver loaded modification improved the mesopore ratio obviously. The oxidative modification considerably enhanced the adsorption capacity and silver loaded modification improved the selectivity against benzene. After three regeneration cycles, the regenerated adsorption afforded 96 and 93% of the initial adsorption capacities of DBT and 4,6-DMDBT respectively. The results suggest excellent reuse ability of the MCs.

Photocatalysis of sulfones for the utilization of the oxidized sulfur compounds by oxidative desulfurization of fuel oil

Photocatalysis of dibenzothiophene (DBT) sulfone and benzothiophene (BT) sulfone for the utilization of the oxidized sulfur compounds by oxidative desulfurization of fuel oil have been investigated. Results show that DBT sulfone, when dissolved in 2-propanol and photoirradiated with high-pressure mercury lamp, can be converted completely into biphenyl in 5 h. However, the photoconversion of BT sulfone can be up to 100 % only in 10 min. The reaction conditions, such as the time of N2 gas bubbled through the solution, distance between the high-pressure mercury lamp and the tube, photoirradiation time and the concentration of sulfones, are all impacted on the photoconversion of DBT sulfone and BT sulfone.