Modelling of UV absorption in a plane photoreactor for solutions with high-patulin concentration

The ratio between the spectral radiant power absorbed and the incident spectral radiant power at the surface was evaluated as a function of the depth of the reactor and the absorbance coefficient, concluding that for a specific absorption coefficient, the absorbed radiation increases asymptotically with the depth of the reactor. The higher the absorption coefficient values, the faster the ratio values increase. The asymptotic value increases if the absorbance coefficient also does because the greater the absorption coefficient, the fewer the beams that exit the solution. For the known values of the absorbance coefficient for fruit juices, it was concluded that almost all the radiation entering the solution is absorbed for depths of much less than 1 mm.