Practice question

Question

A microbial strain is cultured in a 100 L stirred fermenter for secondary metabolite production. If the specific rate of oxygen uptake is 0.4 h^-1 and the oxygen solubility in the broth is 8 mg/L, then the volumetric mass transfer coefficient (KLa) (in s^-1) of oxygen required to achieve a maximum cell concentration of 12 g/L is (up to two decimal places) _________