The present study investigates the volumetric mass transfer coefficient (k(L)a) by the catalyzed sulfite oxidation method at various power inputs, superficial gas velocities, and temperatures in a fully baffled dished base stirred vessel of 0.48 m diameter. A 6-elliptical-blade disk turbine (HEDT) was used as the bottom impeller to disperse the incoming gas, with two up pumping 4-blade hydrofoil impeller (WHU) above. The sodium sulfite concentration was maintained at 500-800 mol.m(-3) and the cobalt catalyst concentration was kept at 0.001 mol.m(-3). Results show that k(L)a increases with the increasing power consumption, superficial gas velocity, and temperature. The effect of power consumption on k(L)a is larger than that of superficial gas velocity on k(L)a. Temperature has an obvious effect on k(L)a with the largest exponent. The correlation k(L)a = 7.37 x 10(-5)P(Tm)(0.63)V(S)(0.34)T(K)(1.64) was obtained in the range of operating conditions used.