Micromechanism of sulfurizing activated carbon and its ability to adsorb mercury

作者:Wu Guofang; Xu Minren; Liu Qingcai*; Yang Jian; Ma Dongran; Lu Cunfang; Lan Yuanpei
来源:Applied Physics A-Materials Science & Processing, 2013, 113(2): 389-395.
DOI:10.1007/s00339-013-7934-6

摘要

To eliminate mercury from coal-fired flue gas, sulfurization of carbons has been found to be the most inexpensive approach to solve the problem of environment contamination by mercury. This study focuses on improving the adsorption capacity of activate carbon loaded with elemental sulfur as an active phase and further use in the removal of mercury vapors from fuel gas. In this paper, equipment such as the scanning electron microscope, specific surface area test machine and fluorescence spectrophotometer are employed to study the ability of the S-loaded activated carbon. The results show that unmodified activate carbon has smooth hole surface and uneven distributed hole size. Pore walls of activate carbon modified became rougher and the hole size distribution is asymmetrical. Sulfur is uniformly distributed and is mainly bonded on the surface of the skeleton of activate carbon. In addition, a small amount of granular sulfur was loaded on the surface of the pore walls. Higher temperature creates smaller pore size and larger microporous volume. Improving the process temperature is conducive to the development of micropore and the distribution of sulfur, and a larger amount of small molecular weight sulfur are created, which is helpful in the removal of HgO through chemical adsorption. The optimum modification temperature and holding time is 550 A degrees C and 60 min, which creates the adsorbents of the max absorption capability of 1227.5 mu g Hg/g.