煤矸石加碱熔融法制备亚微米4A沸石

以煤矸石为原料,采用加碱熔融法制备出亚微米4A沸石,并通过XRD和TEM表征将其与传统水热法合成的4A沸石进行了比较。实验结果表明,加碱熔融法合成4A沸石过程中,固体原料加碱熔融后,不仅可以使煤矸石充分活化,提高沸石产品的结晶度,而且碱与固体原料中的硅、铝在高温下形成均匀的可溶性硅铝酸盐,有效地消除了原料颗粒度对合成沸石的影响,减小了沸石的晶粒度;与传统水热法相比,加碱熔融法合成4A沸石过程的原料煅烧活化温度(700℃)和时间(2h)明显降低和缩短。亚微米4A沸石产品的钙离子交换能力(以CaCO_3/无水沸石计)大于309mg/g,白度高达96%。

Prepration of Submicron 4A Zeolite from Coal Gangue by Alkali-Melting Method

Submicron 4A zeolite was prepared through alkali-melting method and was characterized by means of XRD and TEM.Results indicated that by using the alkali-melting method the coal gangue could be activated fully to improve crystallinity of the product submicron 4A zeolite and soluble homogeneous aluminosilicate could form to reduce grain size of the zeolite.Compared with conventional hydrothermal method,alkali-melting method could lower calcining temperature(700℃) of the raw materials and shorten the calcining time(2h).Whiteness and Ca~(2+)exchange capacity(based on CaCO_3/anhydrous zeolite)of the product submicron 4A zeolite were 96% and more than 309 mg/g.