复合吸附剂的基质选择与动态吸附性能测试

Matrix selection and experimental study on kinetics of composite adsorbent employing lithium chloride in silica gel

用不同类型的粗孔硅胶与氯化锂盐复合制备了一系列复合吸附剂。测量了它们的含盐量,并观察其腐蚀性。对纯硅胶与复合吸附剂的孔结构进行分析。测试了纯硅胶和复合吸附剂吸附水蒸气的性能等。实验证明,作为复合吸附剂的基质,不同类型的硅胶对复合的吸附剂影响很大。纯硅胶中,粗孔粒度为0.5～1.5 mm的硅胶吸附性能相对最好,但吸附量很小;复合吸附剂中,微球粗孔硅胶以及片状大孔硅胶虽然吸附量得到了大大的提高,但不易液解表面的氯化盐,将导致复合吸附剂膨胀结块影响传质通道,并腐蚀吸附床。大于2 mm的粗孔硅胶复合了氯化盐后,吸水产生毛细力将撑破硅胶骨架。因此,最适合复合吸附应用的硅胶基质为小颗粒耐水硅胶。在复合氯化盐后,吸水性能有了很大提高。同时,长时间循环吸附不会造成硅胶粉碎。

Several kinds of silica gel were used to make the different composite adsorbents.The salt content of these composite adsorbents was measured.The corrosion effect was also studied in temperature/humidity equipment.The pore structures of pure silica gel and composite adsorbent were tested.Moisture uptake curves of them were measured.The experiment results showed that as the host matrix of the composite adsorbent,the kind of silica gel impacts on the characteristic of the composite adsorbent.Also the adsorption capacity improves a lot after impregnated salt.The silica gel which is best for the host matrix of the composite adsorbent has the small particle diameter(ranged from 0.5 mm to 1.5 mm).