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应用 VM3000在线测汞仪为检测手段，在固定床实验台架上以银(Ag)改性壳聚糖(chitosan，CTS)/膨润土(bentonite，B)为吸附剂开展了单质汞(Hg0)的脱除研究。采用 N2吸附/脱附、傅里叶变换红外(Fourier transform infra-red spectroscopy，FTIR)和X-射线衍射(X-ray diffraction， XRD)等方法对吸附剂进行结构表征。研究发现，改性后活性银成功负载在吸附剂上，致使壳聚糖及其负载膨润土吸附剂的比表面积发生不同程度的减小；FTIR分析表明CTS和Ag进入膨润土的层状结构，并与膨润土的羟基官能团和Si-O-Si伸缩振动峰发生反应；负载Ag后，吸附剂在2θ=38°处出现了银的特征衍射峰。由于集合了壳聚糖和膨润土两者的优点，壳聚糖的添加可以提高银改性膨润土的脱汞效率。脱汞实验表明 SO2和 HCl 对吸附剂的脱汞效率影响不大，而 NO 和H2O可较大地促进吸附剂的脱汞能力。“,”Adsorption experiments of gas-phase elemental mercury were carried out by using silver (Ag) modified chitosan (CTS)/bentonite (B) in a laboratory-scale fixed-bed reactor. VM3000 online mercury analyzer was applied to detect the inlet and outlet Hg0 concentrations. The characterizations of the sorbents were analyzed by using the method of nitrogen (N2) adsorption/desorption, Fourier transform infra-red spectroscopy (FTIR), and X-ray diffraction (XRD). It is observed that the specific surface areas of the modified sorbents decrease due to the addition of silver. The FTIR spectra demonstrate that CTS and Ag are found in the inlayer of B, and the hydroxyl group and Si-O-Si stretching vibration peak participate in the chemical reaction of modification. The diffraction peak at 2θ=38° attributed to silver appears after modification. Due to the modified sorbent combined with advantages of CTS and B, the addition of CTS can increase the Hg0 removal efficiency of silver modified chitosan/bentonite sorbent. The presences of SO2 and HCl have little influence on Hg0 removal. While both H2O and NO can enhance the adsorption of Hg0.