Acidulation and Regeneration of Bamboo Derived Sorbents for Gas Phase Adsorption of Elemental Mercury

This paper presents results that illustrate the recycling of a bamboo derived sorbent used for the capture of elemental mercury (Hg). The bamboo derived sorbent used is essentially a HCl functionalized activated carbon prepared from carbonization and CO2 activation of raw bamboo, that could potentially provide an alternative way to existing methods in removing mercury from flue gases from coal-fired plants. In this study, the bamboo derived sorbents were tested in a batch test using a mercury permeation tube as the source and nitrogen as a carrier gas. The recycling or regeneration of an activated carbon is an important issue to address from a coal-fired power plant point of view, and an attempt has been made to test the behavior of bamboo derived sorbents with various treatments including carbonized, carbonized-activated, carbonized-activated-acidulated, and then a follow-up recycled run after sample treatments in gas phase. From the study, it was found that bamboo derived activated carbon can be successfully acidulated using various normalities of HCl where weak solutions can be very effective in functionalizing the surface of the sorbent and capturing mercury. In order to recycle and reuse bamboo derived sorbents, stronger normalities of HCl would be desired.