IMPACT OF THE PREPARATION CONDITIONS IN THE SULFUR DISTRIBUTION OF A NEW SULFURIZED POROUS ADSORBENT

Fibrous natural silicates (sepiolite), instead of more conventional ac tive carbon, have been sulfurized to be used as remover agents of merc ury vapors from contaminated industrial waste gases. The Claus reactio n, 2nH2S + nSO2 --> (3n/x)S(x) + 2nH2O, at low temperature (<400 K) an d reactant concentrations (2-3% molar) has been used as the sulfur sou rce, thus being an additional way of eliminating SO2 from metallurgica l processes and urban areas. The process has been carried out in a flu idized bed reactor of the semicontinuous type, and various homogeneous materials with sulfur contents in the range 3-40% S were generated. S ulfur condensation results in catalyst deactivation but, prior to its stabilization as monoclinic sulfur, also acts as cocatalyst of the rea ction contributing to its overall kinetics. A study of the operating c onditions, temperature, reactant concentration, and textural propertie s of the solid on the yield of sulfur deposited has been made. Differe nt pore-plugging mechanisms have been applied, and from them, the infl uence of temperature in sulfur distribution has been concluded. In thi s paper, TA, N2 adsorption at 77 K, and mercury-intrusion porosimetry were used to characterize the resulting adsorbents.