The sulfation experiments of the slurries prepared by using natural trona (NaHCO(3)center dot Na(2)CO(3)center dot 2H(2)O) originating from the Beypazari-Ankara region of Turkey were performed at different conditions. A statistical design technique was applied by the use of a two-level factorial design matrix to interpret experimental results. Sulfation conditions were selected according to a two-level factorial design matrix considering the following variables: sulfation time (3 and 7 h), sorbent content of slurry (1 % and 3 %) and sulfation temperature (298 and 323 K). It was found that the sorbent content of slurry has the strongest effect on the total sulfation capacity in comparison with sulfation time and temperature. The effects of different magnesium and calcium salts on the total sulfation capacities of trona slurries were also investigated. The total sulfation capacities of slurries were increased from 11.45 to 33.00 (mg SO(3)/mL slurry) and from 21.25 to 25.80 (mg SO(3)/mL slurry) with the addition of magnesium and calcium salts, respectively.