Modeling sulfur dioxide uptake in dent corn during steeping

A mathematical model is employed to describe sulfur dioxide (SO2) diffusion and reaction during steeping of dent corn. Experiments are performed to measure change of SO2 content of grain during process. A computer-aided nonlinear optimization technique is used to estimate the effective diffusion coefficients and rate constants in the temperature range 25-55 °C. The effective diffusion coefficient for SO2 varied between 2.27×10−11 and 6.24×10−11 m2/s and had an Arrhenius activation energy of 24.3 kJ/mol. The reaction rate of SO2 in dent corn followed first-order kinetics, with rate constants in the range of 0.80×10−6-5.38×10−6 s−1 and activation energy of 49.16 kJ/mol.