Xin Li,Yilin Xu,Chen Zhang,Hong Wang,Yongji Song,Wei Zhang,Cuiqing Li
Photocatalytic-adsorptive desulfurization of model fuel by the H 2 O 2 -assisted synthesized TiO 2 -SiO 2 (TiO 2 -SiO 2 -H) was investigated using air as the oxidant under UV irradiation. TiO 2 -SiO 2 -H was synthesized hydrothermally in the presence of H 2 O 2 and characterized by scanning electron microscopy (SEM), N 2 adsorption, X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy (UV–vis DRS) and photoluminescence spectrum (PL). Compared to TiO 2 -SiO 2 synthesized in the absence of H 2 O 2 , Ti 0.25 SiO y -H showed greatly enhanced photocatalytic-adsorptive desulfurization performance due to its increased surface area, greatly increased UV absorption and decreased recombination of photogenerated hole/electron pairs. The Ti/Si molar ratio was optimized to 0.3 with the sulfur removal of 100% after reaction for 1 h at the fuel-to-Ti 0.3 SiO y -H weight ratio of 20, and the sulfur content could still be reduced to be <1 ppmw when the fuel-to-Ti 0.3 SiO y -H weight ratio was increased to 80. Moreover, TiO 2 -SiO 2 -H based photocatalytic-adsorptive process bears high selectivity for removing organosulfur in the toluene-containing fuel. The sulfur removal for model fuel containing 25 wt% toluene could reach 98.4% after reaction for 5 h. The photocatalytic-adsorptive selectivity of Ti 0.3 SiO y -H for organosulfur compounds in model diesel fuels followed the order of dibenzothiophene > 4,6-dimethyldibenzothiophene > benzothiophene. The desulfurization performance of TiO 2 -SiO 2 -H was basically stable after four consecutive desulfurization-regeneration cycles.
Lin Chen,Xia Jiang,Wenhua Chen,Zhongde Dai,Jianping Wu,Shenggui Ma,Wenju Jiang
N-doped mesoporous carbon has been used as an efficient metal-free catalyst for hydrogen sulfide (H 2 S) removal. Traditional synthesis methods for mesopore usually are expensive, corrosive, not eco-friendly, and less N-functional groups remained, leading to the poor removal efficiency for H 2 S. This study provides a facile and green synthesis of N-doped interconnected mesoporous biochars (HNBCs) designed from waste biomass with the cross-linked lignin self-template removed by H 2 O 2 . Compared with those without H 2 O 2 (NPC), HNBCs exhibited higher mesopores volume and more basic sites, i.e., pyridinic N (PdN), pyrrolic N (PyN), -C O, and π-π*, which worked as the main active sites. As a result, adding H 2 O 2 increased the breakthrough sulfur capacity to 181 mg/g for HNBC prepared from cypress sawdust, which was about 5 times that without H 2 O 2 (37 mg/g). The desulfurization and regeneration performance were highly related to the cross-linked mesoporous structure and basic sites on the HNBC. This self-template removing method could easily extend to other waste biomass containing lignin and provide an insight into the advantages of efficient biomass self-structure utilization in the biochar designed properly.
危险品化学品经营许可证（带存储）