改性沸石对气态汞吸附的实验研究

为了获得消耗量小、性能高效的燃煤烟气脱汞吸附剂,采用活性MnO2浸渍、FeCl3浸渍和不同温度下渗硫等方法,对沸石进行了改性,制得一系列改性沸石吸附剂。采用固定床吸附的方式,对吸附剂在不同条件下的吸附效果进行了测试,筛选出一种高效、廉价的MnO2浸渍沸石吸附剂,和原沸石吸附剂相比,改性沸石吸附剂对汞蒸气的吸附能力有较大提高,有效吸附时间大大增加,在有效吸附时间内,穿透率大大降低。改性后的沸石吸附能力大大提高的原因在于其吸附过程中,除了物理吸附,还发生了化学吸附。

Experimental study on mercury vapor adsorption with modified zeolite

In order to make small dosage and cost-effective mercury adsorbents for coal-burning flue gas,a series of modified zeolites were prepared by various chemical methods,such as impregnated with MnO2,impregnated with FeCl3 and impregnated with sulfur at different temperatures.A bench-scale testing apparatus was constructed to evaluate the efficiency of mercury adsorbents with fixed bed.The zeolite impregnated with MnO2 was selected out as one kind of effective and low-cost adsorbent.Compared with the zeolite before modification,adsorption capability of modified zeolite was greatly increased;effective adsorption time of them was much longer;its penetration ratio was much lower.The analysis of the adsorbent mechanism of modified zeolite shows that there is chemical adsorption other than physical adsorption during the adsorption process of modified zeolite.