An Environmentally Effective Separation Strategy Of Chitin from Shrimp Shells Based On Steam Explosion and Supercritical Carbon Dioxide

Abstract

The green and efficient separation of chitin is a crucial step for its comprehensive and efficient utilization, while it remains a significant challenge. Herein, we developed a facile strategy for chitin separation from shrimp shells: steam explosion was first performed to disrupt the dense structure and increase the specific surface area of shrimp shells. This improved markedly the efficiency of demineralization and deproteinization via carbonic acid formed in supercritical carbon dioxide/water and high-temperature water, respectively. The high demineralization and deproteinization rates of shrimp shells could thus achieve with this strategy. The separation condition was optimized using response surface methodology. The life-cycle assessment revealed that this strategy has the advantages of carbon dioxide recyclable, chemicals-free, minimal wastewater treatment, and low electricity consumption, offering better environmental benefits than alkali-deproteinization and acid-demineralization. This work provided a new perspective for the green preparation of chitin and exhibited considerable potential for large-scale development and application.

Keywords: Supercritical CO2, minerals, Protein, Chitin, Life Cycle Assessment (LCA)