Clean Technology 2007
R.R. Kotdawala, N. Kazantzis and R.W. Thompson
Worcester Polytechnic Institute, US
molecular simulation, adsorption, mercuric chloride, air pollution, computational chemistry, airborne contaminants
The need to develop technologies capable of achieving high removal efficiencies for mercury chloride emission control led many researchers to focus their attention on the evaluation of the adsorption capacity and selectivity shown by different solids. In the present research study, we make an attempt to understand the physical adsorption of mercuric chloride and mixture of mercuric chloride and nitrogen in zeolite-X and activated carbon through detailed Monte–Carlo simulations and computational quantum chemistry techniques. The Zeolite-X is considered with spherical cavities with sodium cations, as well as activated carbon with slit carbon pores and hydroxyl, carboxyl and carbonyl sites. The capacity of Zeolite-X is compared with activated carbon with different acid sites concentrations, pore sizes by simulating single component mercuric chloride isotherms. The adsorption of binary mixture (N2-HgCl2) is simulated in both types of micropores adsorbents at different HgCl2 concentrations ranging from 5000 ppbv to 10 ppbv in the temperature range of 100 to 180 C. Finally, the selectivity of HgCl2 with respect to N2 is discussed in zeolite–X and as a function of pore size, acid sites concentrations and their relative positions within pore in the case of activated carbon.