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在典型的(NH_4)_2SiF_6与(NH_4Na)Y反应条件下分别研究了(NH_4Na)Y与NH_4F、HCl和NH_4F+HCl以及HY与NH_4F的作用。发现F~-单独不能使(NH_4Na)Y脱骨架铝,HCl也不能使其脱铝(在NH_4Ac缓冲液中),而HCl+NH_4F可使其脱铝并保持较高的结晶度。据此认为(NH_4)_2SiF_6与沸石反应时,沸石的骨架铝是在H~+和F~-的共同作用下逐步脱出的,而不是被F~-抽取掉。根据反应机理提出脱铝沸石中有少量组分性氟存在,水洗不能将其除去。
The effects of (NH_4Na) Y with NH_4F, HCl and NH_4F + HCl, and with HY and NH_4F were studied under the typical reaction conditions of (NH_4) _2SiF_6 and (NH_4Na) Y. It was found that F ~ - alone can not de-aluminate (NH4Na) Y, and HCl can not be dealuminated (in NH4Ac buffer), while HCl + NH4F can de-aluminate and maintain higher crystallinity. According to the above results, it is concluded that the reaction of (NH_4) _2SiF_6 with zeolite leads to the gradual release of the framework aluminum of the zeolite under the action of H ~ + and F ~ - rather than F ~ -. According to the reaction mechanism, there is a small amount of component fluorine in the dealuminated zeolite, which can not be removed by water washing.