煤灰中高熔点矿物质莫来石的实验与量化研究  

Quantum chemistry calculation and experimental study on high-temperature melting point ash mullite

作　　者：陈玉爽[1] 张忠孝[1] 李洁[1] 管嵘清[1] 乌晓江[1] 闫博[1] 

机构地区：[1]上海理工大学动力学院

出　　处：《洁净煤技术》2009年第4期97-100,共4页Clean Coal Technology

基　　金：国家“863”项目(2007AA05Z340)

摘　　要：莫来石是煤灰中高熔点主要矿物质成分之一，笔者采用量子化学的理论和计算方法，对其化学状态，表面化学活性位置及其成键特性进行了研究。计算结果表明，煤灰中莫来石分子簇的最高占据轨道基本是由与Si原子相连接的O7，O12组成，且具有很高的能态。同时，通过计算结果推知煤灰中莫来石表面化学活性强弱关系Al1＋O13〈Al8＋O13〈Al1＋O12〈Si6—O7〈Al8＋O14〈Si6—O12，因此在Al1＋O13，Al8＋O13易断键，使晶格发生重组，量子化学计算从微观方面很好的解释了配煤对降低高灰熔点煤的熔融机理，实验结果也很好的验证了理论计算。Mullite is one of the main mineral compositions in high-temperature melting point ash. The chemistry, reactivity sites and bond-formation characteristics of mullite surface are investigated by using quantum chemistry methods. The results show that the highest occupied molecular orbits （HOMO） of the mullite cluster in the coal ash mainly consists of oxygen atoms 07, O12 connected with the silicon atom, with relative high energy level. Its chemical activity is stronger than the lowest unoccupied molecular orbits （LUMO） of the mullite cluster. Therefore It is prone to combine with electron acceptor, for example Na^＋ , Ca^2＋ and It is difficult to combine with electron donor. At the same, the result shows that mullite surface chemical activity is Al1＋ O 13 〈 Al8 ＋ O 13 〈 Al1 ＋ O 12 〈 Si6 -07 〈 Al8 ＋ O 14 〈 Si6 -O 12 ,therefore the bond in the Al1 ＋ O 13, Al8 ＋ O 13 is so easier broken that lattice is recombined. Quantitative calculation gives a good explanation of blending to reduce the high melting point of coal ash from micro aspects, theoretical calculation has been proved well by experimental.

关 键 词：莫来石 化学活性 量子化学 计算 

分 类 号：TK6[动力工程及工程热物理—生物能]