微波非热效应对有机硫化合物结构的影响

Influence of the non-thermal effect of microwaves on organic sulfur compounds structure

为探究微波辐照脱除煤中有机硫的作用机理以及影响程度,通过核磁共振氢谱、红外光谱和激光共聚焦显微拉曼光谱技术,研究了微波非热效应对有机硫模型化合物结构性能的影响。红外光谱测试说明,微波辐照有机硫化合物存在非热效应并影响化学键的键能分布、基团的振动强度和稳定性,但仅限于分子的极化机制,不会破坏分子中原有的化学键也不会生成新的化学键和基团;核磁共振氢谱揭示非热效应影响了模型化合物分子内部的电子云密度分布和磁环境,对含硫化合物产生的双重极化作用既可改变微观的电子或原子极化,也可改变分子固有偶极矩的取向;显微激光拉曼光谱证明非热效应可有效极化含硫键,使之振动强度减弱,从而有助于有机硫的微波辐射脱除。

In order to explore the mechanism of action and impact degree of removing organic sulfur from coal by microwave irradiation, the proton nuclear magnetic resonance spectroscopy （1HNMR）, Fourier transform infrared spectroscopy （FT-IR） and Raman laser eonfocal spectroscopy （RLCS） techniques were used to investigate the effect of microwave non-thermal on the structural and performance of the model organic sulfur compounds. The FT-IR results showed that the non-thermal effects really existed and could affect the bond energy distribution, vibration strength and stability of the groups, but only on the molecular mechanisms of polarization of organic sulfur compound, not destroyed any original molecule chemical bond or generated new chemical bonds and groups. 1HNMR revealed that the non-thermal effect influenced the electron density distribution and magnetic environment inside the model compound molecular. The dual polarization characteristics of sulfur compounds changed not only the microscopic electron polarization or atomic polarization, but also the orientation of permanent dipole moment. Raman proved that the microwave non-thermal effect could effectively polarize the sulfur-containing chemical bonds, which weakened the vibration intensity, and thus contributed to the remove of organic sulfur from coal.