【摘要】 主要考察了MFI和BEA结构纳米沸石的胶体化学性质 ,对与纳米组装过程直接相关的纳米沸石的电动性质 (主要体现为 ζ电势 )和自聚集性质进行了研究 .考察了pH值、离子强度和硅铝比对沸石 ζ电势的影响 .发现纳米沸石表面电性的变化取决于其骨架结构和组成 ,而电解质浓度的增大可使沸石胶粒的 ζ电势减小 ;pH增大可使 ζ电势向负电性增大的方向变化 .较高的 ζ电势是维持沸石胶液稳定的基本条件 ;而过小的 ζ电势则将导致纳米沸石的聚集或沉降 .在毛细管力作用下纳米沸石可以自组装成沸石纤维 ,沸石的粒径是影响该组装的关键因素 ,沸石粒径越小 ,越容易组装成致密透明的沸石纤维更多还原

【Abstract】 In this paper, the colloidal properties of nanosized zeolites with MFI and BEA topology structure were investigated. It is found that ζ potential of nanosized zeolites varied with the change of zeolite structures and composition. The influences of salt concentration and pH value on the ζ potential of the nanosized zeolites have been studied. With the increase of the salt concentration, the ζ potential gradually decreased and even possessed opposite charges. The effects of ζ potential on the colloidal aggregation and stability are also detected. A cretain ζ potential is necessary to stabilize the zeolite colloid, while too low ζ potential may bring on aggregation of the colloid. At stuitabie temperature, nanozeolite can be self-assembled by capillary force to form transparent self-standing fibers. The crystal size significantly influences the character of the products. The zeolites with smaller crystal size are rather apt to form long, dense and transparent zeolite fibers.更多还原