Effect of transition-metal cations on the adsorption of H2S in modified pillared clays

Sodium montmorillonite was intercalated with the Keggin ion (hydroxyaluminum polycation) and calcined at 400 degreesC. Then, doping with Fe3+, Cu2+ or Zn2+ was carried out. On the obtained samples, H2S breakthrough capacity tests were carried out under wet conditions. Doping with metals significantly improved the capacity of adsorbents, despite a noticeable decrease in microporosity. The sample doped with copper showed the best performance as a hydrogen sulfide adsorbent. The reason for this is likely the affinity of the metal to bind hydrogen sulfide, the degree of metal dispersion, and the accessibility of small pores.