Zn^(2+)抑控煤中α位醛基氧化效果的量子化学研究  

QUANTUM CHEMISTRY ON RESTRAINING OXIDATION EFFECT OF Zn^(2+) ONα-ALDEHYDE STRUCTURE IN COAL

作　　者：戴凤威[1] 邓存宝[1] 邓汉忠[2] 王雪峰[1] 王钰博[3,4] 

机构地区：[1]辽宁工程技术大学安全科学与工程学院,辽宁阜新博士生123000 [2]辽宁工程技术大学材料科学与工程学院,辽宁阜新讲师123000 [3]辽宁工程技术大学矿业工程学院,辽宁阜新博士生123000 [4]大同煤矿集团有限责任公司,山西大同037003

出　　处：《煤炭转化》2016年第1期6-11,共6页Coal Conversion

基　　金：国家自然科学基金资助项目(51274112;51174108);国家科技支撑计划项目(2013BAK06B07)

摘　　要：由于煤化学吸附O_2的过程是煤氧化反应的初始阶段,可通过抑制煤对O_2的吸附来抑制煤的氧化自燃.应用Gaussian 03程序,采用密度泛函(DFT)方法,在B3LYP/6-31G(d,p)水平下研究分析Zn^(2+)与煤中α位醛基结构的作用机理,并以活化能为指标表征Zn^(2+)抑控煤中α位醛基结构氧化的效果,为煤炭自燃的阻化技术研究奠定基础.由计算结果可知,Zn^(2+)的sp^(0.02)d^(0.02)轨道与C_(10)H_7CHO结构的20O原子的sp^(12.20)d^(0.01)轨道杂化形成σ_(Zn-O)配位共价键,此配位共价键的二阶稳定化能为131.84kJ/mol.当C_(10)H_7CHO结构氧化时,首先O_2分子被物理吸附在—CHO基上,形成复合物complexⅠ,并释放30.86kJ/mol的能量,然后复合物complexⅠ的分子间发生化学作用,导致O_2分子被化学吸附在—CHO基上,所需活化能为Ea=66.87kJ/mol;当煤中的活性α位醛基与Zn^(2+)形成[ZnOHCC_(10)H_7]^(2+)配合物后,—CHO基物理吸附O_2分子释放的能量减少了19.38kJ/mol,且化学吸附所需活化能增加了52.34kJ/mol.因此,Zn^(2+)对煤中α位醛基氧化具有明显的控制作用.Oxidation and spontaneous combustion of coal could be controlled by restraining coal chemical adsorption O_2,because the initial stage of coal oxidation is the process of coal chemical adsorption O_2.Using the Gaussian 03 program,the mechanism of interaction of Zn^2＋andα-aldehyde structure in coal is studied by using density functional theory（DFT）method at the B3LYP/6-31G（d,p）level.And the restraining oxidation effect of Zn^2＋onα-aldehyde structure in coal is characterized by activation energy to provide base for studying technology of inhibition coal spontaneous combustion.The results show that sp^（0.02）d^（0.02） orbital of Zn^2＋and sp^12.20d^0.01 orbital of 20 Oatom in C_（10）H_7CHO structure hybridize forming σ_（Zn-O） coordinate-covalent bond,its second order energy is 131.84kJ/mol.When C_（10）H_7CHO structure is being oxidized,the first step is that O_2 is adsorbed physically onto —CHO group to form complexⅠ,and release heat 30.86kJ/mol.Secondly,O_2 is adsorbed chemically onto it by chemical action of the molecules in complexⅠ.The activation energy is Ea=66.87kJ/mol during the whole process.After forming[ZnOHCC_（10）H_7]^（2＋） coordination complex byα-aldehyde structure in coal with Zn^2＋,the heat released by —CHO group physically adsorbing O_2 is decreased 19.38kJ/mol,and the activation energy of chemical adsorption is increased 52.34kJ/mol.Consequently,we can get the conclusion easily that inhibition effect of Zn^2＋onα-aldehyde structure in coal is particularly noticeable.

关 键 词：α位醛基 量子化学 阻化 吸附 活化能 

分 类 号：TQ534[化学工程—煤化学工程] O641.121[理学—物理化学]