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在三乙胺-氢氧化铝-磷酸-水体系中,150～200℃条件下,采用水热法合成了AlPO_4-5分子筛,在1400～400cm~(-1)区间内,对它的晶化、灼烧、吸附与脱附氨的过程进行了红外跟踪测定。同时,还采用了计算机分峰的新技术——微分光谱(二次导数红外光谱,简称为2DIR光谱),将测得的IR谱带进行了分峰处理。结果表明:采用三乙胺为模板剂合成的AlPO_4-5的特征IR谱带峰位在1125(强)、736(弱)、705(弱)、630(弱)、560(中)、473(较强)cm~(-1)处。并在1220cm~(-1)附近存在一个肩峰。经2DIR处理后,1220cm~(-1)附近的肩被分离成一个独立峰,在晶化初期就可以被2DIR光谱分辨出来,在IR谱图中,1125cm~(-1)处的强吸收带经2DIR处理后,可以分离出1166、1124、1093、1072及1019cm~(-1)等几个峰。这些被2DIR分离出来的谱峰,在AlPO_4-5分子筛的晶化、灼烧及对氨的吸附与脱附过程中,都发生了有规律的变化。我们发现1093、1072和1019cm~(-1)谱峰与羟基振动有关。根据这些谱带在AlPO_4-5的灼烧、吸附与脱附过程中的变化,1093cm~(-1)谱峰可归属于P—OH键的弯曲振动,而1072cm~(-1)谱峰可归属于(?)的弯曲振动。
AlPO 4 -5 zeolite was hydrothermally synthesized in the triethylamine-aluminum hydroxide-phosphoric acid-water system at 150 ~ 200 ℃, and its crystallization was carried out in the range of 1400 ~ 400cm -1 , Burning, adsorption and desorption of ammonia in the process of infrared tracking. At the same time, we also use the new technology of computer split-differential spectroscopy (second derivative infrared spectroscopy, referred to as 2DIR spectroscopy), the measured IR bands were peaked. The results showed that the characteristic IR bands of AlPO_4-5 synthesized by using triethylamine as template were at 1125 (strong), 736 (weak), 705 (weak), 630 (weak), 560 (middle), 473 ( Strong) cm ~ (-1) Department. And there is a shoulder near 1220cm ~ (-1). After 2DIR treatment, the shoulder near 1220cm ~ (-1) was separated into an independent peak, which was resolved by 2DIR spectroscopy at the early stage of crystallization. In the IR spectrum, the strong absorption band at 1125cm ~ (-1) After 2DIR treatment, several peaks of 1166, 1124, 1093, 1072 and 1019 cm -1 could be separated. These peaks separated by 2DIR have regular changes in the crystallization, burning and adsorption and desorption of ammonia on AlPO 4 -5 zeolite. We found that the 1093, 1072 and 1019 cm -1 peaks are related to hydroxyl vibration. According to the change of these bands during the burning, adsorption and desorption of AlPO 4 -5, the peak at 1093 cm -1 can be attributed to the bending vibration of P-OH bond, while the peak at 1072 cm -1 Bending vibration attributable to (?).