改性活性炭吸附甲醛的影响因素研究

Study on Influencing Factors of Modified Activated Carbon Adsorption of Formaldehyde

利用浸渍法制备出以柱状活性炭为基材负载高锰酸钾(KMnO4)的复合型甲醛吸附材料,利用比表面积及孔隙度分析测试仪和场发射扫描电子显微镜观察活性炭改性前后的物理结构变化,搭建单通道滤料性能测试实验台研究高锰酸钾负载率、气体相对湿度、重复负载次数对改性活性炭吸附甲醛的性能影响。结果表明,未负载KMnO4的活性炭对甲醛的吸附性能最差,负载率为5%、10%、20%、24%的改性活性炭比未改性活性炭吸附容量增大1.1、3.5、4.5、5.5倍,最佳负载率为24%;KMnO4负载率10%的改性活性炭在相对湿度为20%、50%的情况下比相对湿度80%时,甲醛吸附容量增大1.5、1.3倍。改性活性炭失活后,重复负载KMnO4 1次仍表现出良好的甲醛吸附性能;但重复负载两次后改性活性炭的甲醛吸附性能下降明显。

A composite formaldehyde adsorption material loaded with potassium permanganate(KMnO4) using columnar activated carbon as the base material was prepared by the impregnation method.Observe the physical structure changes of activated carbon before and after modification with specific surface area and porosity analysis tester and field emission scanning electron microscope.A single-channel filter material performance test bench was built to investigate the effect of potassium permanganate loading rate, gas relative humidity, and repeated loading on the adsorption of formaldehyde by modified activated carbon.The results show that activated carbon without potassium permanganate has the worst formaldehyde adsorption performance.Modified activated carbon with a loading rate of 5%,10%,20%,and 24% has an increased adsorption capacity of 1.1,3.5,4.5 and 5.5 times compared with unmodified activated carbon.Modified activated carbon with a loading rate of 10% increases the formaldehyde adsorption capacity by 1.5 and 1.3 times when the relative humidity is 20% and 50% compared to 80% relative humidity.After the modified activated carbon was deactivated, KMnO4 was repeatedly loaded once still showed good formaldehyde adsorption performance.However, the formaldehyde adsorption performance of the modified activated carbon decreased significantly after repeated loading twice.