Degradation of chitosan by hydrodynamic cavitation

A novel method of degradation of chitosan, by hydrodynamic cavitation using an orifice plate, was investigated. The effects of initial concentration, solution pH, upstream pressure and geometry of the orifice plate on the degradation of chitosan were evaluated. It was found that lower initial concentration of chitosan solution, lower solution pH, higher upstream pressure of the orifice plate, and longer treatment time are favourable for the degradation of chitosan solution. It was also found that the degradation of chitosan solution was dependant on the geometry of the orifice plate. The plates with a larger number holes and smaller hole diameter favoured chitosan degradation. Structures of the degraded products were characterized with Fourier-transform infrared spectra (FT-IR) and X-ray diffraction (XRD). The present study conclusively establishes that hydrodynamic cavitation can be effectively used for the degradation of chitosan.