Development of low-concentration mercury adsorbents from biohydrogen-generation agricultural residues using sulfur impregnation

作者：Hsi Hsing Chengi^*; Tsai Cheng Yen; Kuo Tien Ho; Chiang Cheng Sheng

来源：Bioresource Technology, 2011, 102(16): 7470-7477.

DOI：10.1016/j.biortech.2011.05.036

• Mercury
• Adsorption
• Surface modification
• Biotreated waste
• Activated carbon

Mercury adsorbents were derived from waste biohydrogen-generation barley husk and rice husk via carbonization, steam activation, and sulfur impregnation at 300-650 degrees C. The samples derived from agricultural residues showed a greater Hg(0) adsorption than that of a coal-based activated carbon, confirming the feasibility of resource recovery of these agricultural residuals for low-concentration gaseous Hg adsorption. Sulfur impregnation reduced both the surface area and pore volume of the samples, with lower temperature causing a greater decrease. Elevating the impregnation temperature increased the organic sulfur contents, suggesting that in addition to elemental sulfur, organic sulfur may also act as active sites to improve Hg(0) adsorption. Oxygen and sulfur functional groups accompanying the microporous structures may account for the enhancing Hg adsorption of the raw and sulfur-treated samples, respectively. The pseudo-second-order model can best describe the chemisorption characteristics, implying that Hg adsorption on the samples was in a bimolecular reaction form.

• 出版日期2011-8