摘要
采用X射线近边结构谱(XANES)研究沥青质中硫的存在形态,针对沥青质的未知复杂混合体系特性,采用高阶导数谱图分析方法,提高XANES的分辨率,准确分析沥青质中硫的存在形态;采用反正切和高斯函数分峰拟合、定量解析谱图,针对不同氧化态硫3p轨道空余状态不同引起1s→3p跃迁几率不同,提出峰面积修正因子,以准确分析体系中各形态硫的相对含量。结果表明,石油沥青质中硫主要存在形式为硫醚、噻吩、亚砜、噻吩砜和硫酸酯,常减压渣油沥青质中基本不含硫醚。
The XANES spectrum is employed to study the sulfur functional groups in asphaltenes. Since the asphaltenes are complicated mixture, it is difficult to distinguish different classes of sulfur compounds in asphaltenes. Therefore, the higher order derivative spectra of sulfur XANES were introduced in order to improve sulfur XANES resolution and to qualitatively analysis sulfur functional groups in asphaltenes. Sulfur XANES spectra were deconvoluted by using of several Gaussian and arctangent functions to quantify the sulfur species. In order to convert peak area percentages to atomic percentages, the relative l s→3p transition probabilities of different sulfur classes must be considered. The areas of the different Gaussian peaks were calculated and revised for their oxidation state-dependent absorption cross-section. The contribution of sulfur species to total sulfur was calculated by the corrected peak areas. The result showed that sulfur species in asphaltenes of atmospheric and vacuum residue were mainly in form of thiophene, sulfoxide, thiophene sulfone and sulfate, while hardly contained sulfide.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2013年第11期1328-1335,共8页
Journal of Fuel Chemistry and Technology
基金
国家自然科学基金(20776160)
重质油国家重点实验室开放课题资助
中石油重大科技专项专题
中国石油大学(华东)"青年教师拔尖人才建设工程"
