煤系高岭岩合成分子筛的转化机理  

Synthesis mechanism of molecular sieve from Kaolinite rock in coal measure

作　　者：李凯琦[1] 韩星霞[1] 

机构地区：[1]焦作工学院资源与环境工程系,河南焦作454000

出　　处：《煤炭学报》2003年第3期294-298,共5页Journal of China Coal Society

基　　金：原煤炭部科技攻关资助项目(93-372);河南省科技攻关资助项目(991190206)

摘　　要：由于对煤系高岭岩与化工原料的成分、结构等特征的差异性认识不足,导致了煤系高岭岩合成分子筛机理的一些缺陷,影响了高岭岩合成分子筛开发利用研究的深入,笔者旨在解决一些与煤系高岭岩合成分子筛有关的理论问题,促进该学科领域的发展.通过对高岭岩合成分子筛过程中SiO2,Al2O3含量及变化特征、分子筛"团聚体"形貌特征、合成分子筛试验及结晶动力学特征等因素的综合分析,得出:①高岭岩(土)向分子筛的转化是一个以固体状态下直接转化为主,溶液中结晶为辅的复杂过程,并且没有真正的胶体状态存在;②在均匀体系中,分子筛晶体的生成有一个"诱导期"(晶核形成期),该阶段和晶化阶段的性质不同;③在合成分子筛的反应体系中,Fe2O3的行为与Al2O3类似,它只影响分子筛产品白度,而K+,Ca2+,Mg2+是影响分子筛晶体生长的主要杂质.Because the understanding about the difference between Kaolinite rock in coal measures and chemical materials in composition and structure is insufficient, there are some limitations on the investigation of the synthesis mechanism of molecular sieve from Kaolinite rock in coal measures. Therefore, the development and utilization of synthesis molecular sieve from Kaolinite rock is not extensive. Some theoretic problems about the synthesis molecular sieve from Kaolinite rock will be discussed. This research will enhance the progress of the discipline. Based on the systematical analyses about the content and variety of SiO2  to Al2O3, the aggregate phase of molecular sieve, synthesis molecular sieve experiment, and the crystallization dynamics during the process of synthesis molecular sieve, the authors suggest the following conclusions:① The transformation from calcined Kaolin to molecular sieve is mainly under solid state, seldom crystalized from liquid and no colloid formed; ② In a homogeneous system, there is a revulsive period (to form crystal core), and this stage is different from crystalline stage in character; ③ In the reactive system of synthesis molecular sieve, the behavior of Fe2O3 and Al2O3 is similar. Fe2O3 only controls the whiteness of molecular sieve. K+, Ca2+, and Mg2+ are mainly the impurities that influence the growth of molecular sieve crystals.

关 键 词：高岭岩 分子筛 4A沸石 转化机理 

分 类 号：P619.232[天文地球—矿床学]