掺硫介孔炭的制备及其汞脱除特性

采用模板法，以MCM-41为模板剂，2-噻吩乙醇和百里香酚蓝为前体，制备了掺硫介孔炭吸附剂，在固定床汞吸附实验装置上研究了其脱汞性能，考察了前体质量比、煅烧温度、烟气温度与烟气组分（O₂、SO₂）等因素对其脱汞性能的影响，并对吸附剂的物化特性进行了表征，分析了其脱汞特性。结果表明：在前体（2-噻吩乙醇∶百里香酚蓝）质量比为6∶1、煅烧温度为900℃时制备获得的掺硫介孔炭MCM-900-1∶6的脱汞效率最高，其比表面积达932m²/g，C质量分数为81.12%，S质量分数为10.24%；MCM-900-1∶6脱汞温度区间较广，在50～150℃下脱汞效率高达90%；MCM-900-1∶6有着良好的抗SO₂干扰能力，O₂对其脱汞有一定的促进作用；随着煅烧温度上升，掺硫介孔炭的分层现象消失且变得更加规整；FTIR表明900℃煅烧后，掺硫介孔炭的C＝S取代O―H成为数量最多的官能团；XPS分析表明，掺硫介孔炭表面主要为噻吩硫与单质硫，它们对脱汞起主要作用。

Preparation of sulfur-doped mesoporous carbon and its mercury removal

The template method was used to prepare sulfur-doped mesoporous carbon sorbents with the template agent of MCM-41 and the precursors of 2-thiophene ethanol and thymol blue. Mercury removal performance of sorbents was studied in a fixed bed experimental device and the effects of precursor mass ratio, calcination temperature, flue gas temperature and composition (O₂, SO₂) on mercury removal were investigated. The physical and chemical properties of the sorbents were characterized to analyze the mercury removal mechanism. The results showed that when the precursor (2-thiopheneethanol∶ thymol blue) mass ratio was 6?∶?1 and the calcination temperature was 900℃, the prepared MCM-900-1∶6 displayed the highest mercury removal rate. The specific surface area of the MCM-900-1∶6 was 932m²/g and the contents of C and S were 81.12% and 10.24%, respectively. The MCM-900-1∶6 had a wide temperature range of mercury removal, and the mercury removal efficiency was as high as 90% at 50—150℃. The MCM-900-1∶6 indicated a good resistance to SO₂, and O₂ somewhat promoted mercury removal. With rising calcination temperature, the layering phenomenon disappeared and the mesoporous carbon became more regular. FTIR analysis showed that after calcination at 900℃, the C＝S replaced O－H to become the most abundant functional group. XPS analysis found that the sulfur on the mesoporous carbon surface was thiophene sulfur and elemental sulfur, which played a major role in mercury removal.