Abstract:

In order to improve the efficiency and reduce the energy consumption in the desalination of fibroin solution, the diffusion dialysis and electrodialysis membrane separation technique was applied to the desalination process, and the application properties of the silk fibroin solution were preliminarily explored. Factors affecting the desalting efficiency and energy, such as the concentration of silk fibroin and the pre-desalination rate were investigated. Moreover the insoluble silk fibroin powder was prepared by adding anhydrous ethanol to the silk fibroin solution, the amino acid composition of the product was determined and the silk fibroin powder was characterized by scanning electron microscopy. The results show that the optimal parameters for desalting is 5% of the concentration of silk fibroin and  40% of the pre-desalination rate. Under this condition, the desalination time is shortened to 9 h and the energy consumption (except dynamic power consumption) is 3.81x10-2 kw?h/L；the total content of serine and glycine in the product is close to 50%, and scanning electron microscopic results show that the particle size of the powder is smaller and the distribution is uniform.

Key words: silk fibroin, desalination process, diffusion dialysis, electrodialysis, silk fibroin powder