Preparation of consolidated zeolite body using mechanochemical phenomena and its application to removal of heavy metals

利用力化学现象制备固结沸石体及其在去除重金属中的应用

基本信息

批准号：
16550168
负责人：
SHIONO Takeshi
金额：
$ 1.98万
依托单位：
Kyoto Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2005
项目状态：
已结题

项目摘要

Inorganic consolidated bodies were synthesized from water-glass (potassium or sodium silicate solution) and aluminum hydroxide. The possibility of transition of the consolidated body to bulky zeolite body was investigated. Mechanochemical effect of aluminum hydroxide on formation zeolite phase was also investigated. The removal capability of the synthesized bulky zeolite was estimated.For system of zeolite composed of potassium, zeolite F was synthesized when the precursor was heat-treated at a temperature higher than 140℃. The formation temperature was dependent on the amount of potassium. Addition of potassium remarkably decreased the formation temperature zeolite. For composition of K:Al:Si=1:1:1 in starting materials, for example, heat-treatment temperature higher than 140℃ was required to form zeolite phase. For composition of K:Al:Si=1.5:1:1 and K:Al:Si=2:1:1, on the contrary, the temperature decreased to 80℃ and 60℃, respectively. All of synthesized zeolites with different chemical composition were identified as type F. Excessive addition of potassium deteriorated the water resistance of the consolidated zeolite and the zeolite broke down in water.For system of zeolite composed of sodium, on the contrary, monolithic zeolite A (Na:Al:Si=1:1:1) could be synthesized as a consolidated body. Crystalline phase was greatly dependent on particle size of aluminum hydroxide as a starting material without mechanochemical treatment. For larger particle, faujasite type zeolite was synthesized and smaller particle promoted to form A type zeolite. In addition, mechanochemical treatment was very effective to synthesize monolithic zeolite A. The mechanochemical treatment had much effect on formation temperature of zeolite A. Aluminum hydroxide powder treated mechanically made the heat-treatment temperature of 60℃ enough to form bulky zeolite A.Both of zeolites, type F and type A, exhibited good characteristic of removal for heavy metals such as Pb and Cd.

由水玻璃（硅酸钾或硅酸钠溶液）和氢氧化铝合成无机固结体，并研究了氢氧化铝对形成沸石相的机械化学作用。对合成的大块沸石的性能进行了评估。对于由钾组成的沸石体系，当前驱体在一定温度下热处理时合成了沸石F高于140℃时，形成温度取决于钾的量，对于起始材料中K:Al:Si=1:1:1的组成，例如热处理，沸石的形成温度异常降低。对于K:Al:Si=1.5:1:1和K:Al:Si=2:1:1的组成，需要温度高于140℃才能形成沸石相，反之，温度降低至80℃即可。 60℃下，不同化学组成的合成沸石均被鉴定为F型。过量的钾添加使固结沸石的耐水性变差，沸石在水中分解。对于钠组成的沸石体系则相反。，整体式沸石 A (Na:Al:Si=1:1:1) 可以合成为固结体，晶相很大程度上取决于作为起始原料的氢氧化铝的粒径。对于较大颗粒的材料，合成了八面沸石型沸石，而较小的颗粒则促进形成A型沸石。此外，机械化学处理对于合成整体式A型沸石非常有效。机械化学处理对A型沸石的形成温度有很大影响。机械处理的氢氧化铝粉末，在60℃的热处理温度下足以形成大块沸石A。两种沸石，类型。 F型和A型，对Pb、Cd等重金属表现出良好的去除特性。