绿泥石矿制备Na-X分子筛

Preparation of Na-X Zeolite from Chlorite

绿泥石化学成分以SiO_2、Al_2O_3为主,是合成分子筛的主要原料。由于绿泥石中存在Fe和Mg元素,为减少杂质对分子筛合成的影响,将绿泥石与Na_2CO_3进行煅烧活化,采用水和碱性溶液浸出绿泥石中的硅和铝离子,并通过ICP检测分析硅和铝的提取率,进一步确定制备Na-X型分子筛的工艺参数。结果表明,采用Na_2CO_3预处理后绿泥石的硅和铝溶出率分别达到71%和67%。经SEM、XRD和FT-IR分析表明,Na-X型分子筛纯度较高,晶型完整,无其他杂质,热稳定性高,颗粒大小均匀,尺寸在1~2μm左右;Na-X分子筛的吸附行为符合Ⅰ型等温线,具有均匀的孔径,孔径主要区间为0.4~0.8 nm,为微孔吸附剂。此外,制备的Na-X分子筛满足中国化工行业标准(HG/T 2690-95)要求(吸水率大于23%)。

The chemical components of chlorite are mainly SiO_2、Fe_2O_3 and Al_2O_3,which are the main materials to prepare zeolite. Because of the higher Fe and Mg content of chlorite,in order to reduce the influence of impurities on the synthesis of zeolite,chlorite were activated with Na_2CO_3 by calcination,then silicon and aluminum ions in activated chlorite were leached by water and alkaline solution. ICP detection results showed that silicon and aluminum extraction rates of chlorite after pretreatment with Na_2CO_3 reach 71% and 67%,respectively. In addition,SEM,XRD,and FTIR analyses showed that the self-prepared Na-X zeolite has high purity,complete crystal form,good thermal stability,and uniform particle size（ about 1 - 2μm）. The as-prepared Na-X zeolite is a microporous adsorbent with average pore size range of 0. 4 - 0. 8 nm. In addition, the prepared Na-X zeolite meets the requirements of the Chinese chemical industry（ HG/T2690-95）（ water absorption rate is greater than 23%）.