Diatomite supported bagel-like hydroxylated mesoporous carbon nitride towards the adsorption desulfurization application

Abstract

The carbon nitride (g-C3N4) nanosheets was apt to occur the donor-acceptor (D-A) interaction with the sulfides via the influence of the electronic structure of C atoms in the ring. Accordingly, we implemented an environmental- friendly approach to raise the electropositivity of the C atoms of N atoms in the ring of g-C3N4 through the hydroxylation treatment of hydrogen peroxide(H2O2), and afterwards constructed a bagel-like morphology composite ((HO)x/g-C3N4@DE) by virtue of the calcined combination of hydroxylated mesoporous g-C3N4 and diatomite (DE). The characterization results showed that the substantial mesoporous structure was produced in the formation of (HO)x/g-C3N4@DE composite. The adsorption desulfurization experiments showed that the bagel-like hydroxylated mesoporous (HO)x/g-C3N4@DE had the optimum adsorption capacity of up to 42.2 mg/g for thiophene (TH) and 30.8 mg/g for benzothiophene (BT), respectively. Moreover, the adsorption capacities of the hydroxylated mesoporous (HO)x/g-C3N4@DE were dramatically higher than the individual (HO)x/g-C3N4 (18.92 mg/g for TH and 15.64 mg/g for BT), suggesting that the occurrence of the secondary stacked mesopores in the formation of the (HO)x/g-C3N4 on the surface and macro-porous structure of DE affected the adsorption capacity. Lastly, the adsorption mechanism of the hydroxylated mesoporous (HO)x/g-C3N4@DE was proposed.