【作者】 赵庆福；

【导师】 王继仁；

【作者基本信息】 辽宁工程技术大学 ， 采矿工程， 2009， 博士

【摘要】 针对煤炭自燃阻化技术的理论基础研究薄弱的问题,首次应用量子化学理论从微观上系统地研究了预防煤炭自燃阻化技术基础理论,应用密度泛函理论,在B3LYP/6-311G水平上研究了煤含氮、磷、硫的活性基团与阻化剂形成的配位化学键和配位体的过程,创立了预防煤炭自燃的阻化机理理论,其核心内容是煤有机大分子和低分子化合物中含氮、磷、硫、氧等活性基团与阻化剂中的金属离子形成配位化学键和配位体,惰化了煤中的活性基团与氧反应的活性,突破了传统理论的附着煤表面的强盐在吸水后煤表面形成水膜隔氧的学术观点。填补了预防煤自燃阻化机理研究领域的空白。主要研究内容和研究成果概括如下:通过红外光谱实验研究及量子化学计算,在建立了煤分子结构模型的基础上,采用量子化学密度泛函（DFT）理论计算方法,在B3LYP/6-311G计算水平上,得出煤分子的结构模型及简化后的煤分子的前沿轨道图,确定煤分子中的活性基团-NH₂、-PH₂及-SH具有较高的化学活性容易失去电子与金属离子形成配位键,同时也易于氧发生化学反应导致煤炭自燃。研究了煤分子活性基团与Mg²⁺、Na⁺离子形成配位化学键及配位化合物的过程,通过对形成配合物的自然键轨道、净电荷布居及自然电子组态计算及分析,发现煤分子中的N、P、S原子的孤对电子与Mg²⁺、Na⁺离子的孤对电子及价外层空轨道有强的相互作用能,同时Mg²⁺、Na⁺离子的原子轨道从配体得到部分反馈电子,导致偏离其表观电荷,说明Mg²⁺、Na⁺离子与配体中的N、P、S原子形成了配位键。通过对配合物的稳定化能和前沿轨道能级分析,得到Mg²⁺与煤中的N、P、S活性基团形成的四配位化合物最为稳定,Na⁺与煤中的N、P、S活性基团形成的三配位化合物最为稳定,而Na⁺与煤含P活性基团形成四配位化合物稳定性差。Mg²⁺与煤中的N、P、S活性基团形成配合物时的稳定化能远大于Na⁺与煤中的N、P、S活性基团形成配合物时的稳定化能,最大为6.81倍,最小为2.14倍,得到Mg²⁺与煤中的N、P、S活性基团形成配合物的稳定性强于Na⁺与煤中的N、P、S活性基团形成配合物的稳定性,因此Mg²⁺阻化效果强于Na⁺。从而揭示了预防煤炭自燃阻化机理的本质是煤活性基团与金属离子形成配位化学键和配位体,惰化了活性基团与氧反应的活性。从微观方面解决了Mg²⁺、Na⁺离子能够预防煤氧化自燃的理论问题。更多还原

【Abstract】 Because basic research of the theory about inhibition technology for coal spontaneous combustion is not adequate,the quantum chemistry theory is used to study the basic theory about inhibition technology for preventing coal spontaneous combustion In microcosmic view for the first time.With B3LYP/6-311G density functional theory is used to study the process of forming coordination chemical bond and ligand between active groups of coal including N,P,S and inhibitor.The theory of inhibition mechanism for preventing coal spontaneous combustion is founded.The core content is that coordination chemical bond and ligand between active groups including N,P,S,O,etc in organic macromolecule and low molecular weight compounds of coal and metal ions in inhibitor are formed,which decrease the reaction activity between oxygen and active groups.It is a breakthrough of traditional theory and academic view that water film,separating oxygen,is formed on coal surface after strong salts attaching there absorb water.It also fills the gaps in field of studying inhibition mechanism for preventing coal spontaneous combustion. The main research contents and achievements are as follows:Through infrared spectrum experimental study and quantum chemistry calculation, based on the molecular structure model of coal,on B3LYP/6-311G density functional theory is used to obtain structure model and frontier orbital figure of coal molecule after simplification and determine that active groups like-NH₂,-PH₂,and-SH in coal molecule have high chemical activity and therefore are easy to loss electron and form coordination bond with metal ions,and at the same time coal spontaneous combustion is easy to happen.The process of forming coordination chemical bond and coordination compound between active groups of coal molecule and ions like Mg²⁺ and Na⁺ is studied.After calculating and analyzing natural bond orbital,net charge population and natural electron configuration of forming complex,strong interaction energy between lone pair electrons of atoms like N,P,S in coal molecule and ions like Mg²⁺ and Na⁺ and unoccupied orbital is discovered.Meanwhile,atomic orbital of ions like Mg²⁺ and Na⁺ gets part of feedback electrons from ligand and deviates its apparent charge,which illustrate that coordination bond is formed between Mg²⁺,Na⁺ and N,P,S in ligand.After analyzing stabilization energy and frontier orbital energy level,it is obtained that four-coordination and three-coordination compounds forming from Mg²⁺ and active groups N,P,S are the most stable,and four-coordination compounds forming from Na⁺ and active group P is not.Stabilization energy of complex forming from Mg²⁺ and active groups N,P,S is far more than that from Na⁺ and active group N,P,S.The maximum energy from the former one is 6.81 times than that from later one,and the minimum energy from the former one is 2.14 times than that from later one.Stability of complex forming from Mg²⁺ and active groups N,P,S is higher than that from Na⁺ and active group N,P,S.Therefore,it is showed that the essence of inhibition mechanism for preventing coal spontaneous combustion is coordination chemical bond and ligand between active groups of coal and metal ions are formed,which decrease the reaction activity between oxygen and active groups.Theoretical problem of Mg²⁺,Na⁺ preventing coal spontaneous combustion is solved from microcosmic view.更多还原