Non-isothermal kinetics of thermal degradation of chitosan

摘要: Chitosan is the second most abundant nitrogen containing biopolymer in nature, obtained from shells of crustaceans, particularly crabs, shrimp and lobsters, which are waste products seafood processing industries. It has great potential application areas biotechnology, biomedicine, food industries, cosmetics. also capable adsorbing a number metal ions as its amino groups can serve chelation sites. Grafted functional such hydroxyl, carboxyl, sulfate, phosphate, on chitosan have been reported to be responsible for binding sorption dyes pigments. The knowledge their thermal stability pyrolysis may help better understand plan industrial processing. Thermogravimetric studies air atmosphere were carried out at six rates linear increasing temperature. kinetics mechanism decomposition reaction evaluated TG data using recommended ICTAC committee iso-conversional calculation procedure Kissinger-Akahira-Sunose, well 27 functions. comparison results showed that they strongly depend selection proper function process. Therefore, it very important determine probable function. In this respect turned appropriate. excellent properties hydrophilicity, biocompatibility, biodegradability, antibacterial, non-toxicity, adsorption application. degradation occurs two stages. both stages determined was best described by kinetic equations n-th order (Fn mechanism). For first stage, established n equal 3.0 stage – 1.0 respectively. values apparent activation energy E, pre-exponential factor A Arrhenius equation, changes entropy ΔS≠, enthalpy ΔH≠ free Gibbs ΔG≠ formation activated complex reagent calculated.