摘要
通过离子交换法制备了一系列的改性ZSM-5分子筛催化剂,用真空原位红外对分子筛催化剂进行了表征,绘制了分子筛的红外光谱图。通过红外光谱图使用谱带积分法计算了布朗斯台德酸(Brnsted酸)和路易斯酸(Lewis酸)的酸浓度,推导了ZSM-5分子筛催化尿素脱水的催化过程机理。使用改性后的ZSM-5分子筛催化剂催化尿素脱水的反应,结果表明,改性后ZSM-5分子筛催化剂的催化性能明显优于未改性的HZSM-5。
A series of modified-ZSM-5 molecular sieve catalysts are prepared by ion exchange method. The molecular sieve catalysts were characterized by vacuum in situ infrared,and a infrared spectra are drawn. The acid concentration of Brnsted acid and Lewis acid is calculated by infrared band spectroscopy using band integration method. And the catalytic mechanism of ZSM-5 molecular sieve catalyzed urea dehydration is deduced. The modified-ZSM-5 molecular sieve catalyst is used to catalyze the dehydration of urea,the results show that the catalytic performance of ZSM-5 zeolite catalyst after modification is better than that of unmodified HZSM-5.
引文
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