Synthesis and characterization of hybrides membranes composed of chitosan, polyvinyl alcohol and silica for its application in dehydration of gases
The membrane systems are an attractive technology applied to separation process. For decades, the synthesis and characterization of its properties have been studied focusing its development of efficient and competitive membrane systems. In order to study the feasibility of the utilization of synthesized hybrids membranes to the process of gases dehydration, dense membranes composed of chitosan, polyvinyl alcohol and silica were elaborated applying the solution casting method, considering different compositions, thickness and studying its permeability of water vapor. It was found that chitosan (CTS) quantity is the variable that affects more significantly the permeated. In addition, the influence of the time and the glutaraldehyde concentration in the crosslinking process was evaluated. The experimental results showed that selected parameters do not have influence on permeate, only physical-chemical features of the membrane. Lastly, the membranes were characterized with three methods: (1) Infrared Spectroscopy (FTIR) that show internal structure changes with the crosslinking, (2) Differential scanning calorimetry that evidence changes in the thermal transitions and (3) Thermogravimetric Analysis (TGA) that show the temperatures of degradation of the membranes.
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