Hydrolysis of Chitin with Acid and Noble Metal Catalyst

Chitin, abundant in shrimp and crab shells, can be hydrolyzed to produce glucosamine, a compound widely used in medicine, agriculture, and material science. Efficient production of chitin monomers and their derivatives on a large scale can enhance the utilization of marine resources and reduce environmental pressure. However, current hydrolysis methods face technological and cost-related challenges, limiting them to experimental or small-scale production. This study explores the hydrolysis of chitin using acids, salts, and activated-carbon-supported transition metals, focusing on optimizing reaction parameters for improved monomer yield. Among six acids tested, hydrochloric acid yielded the highest amount of N-acetyl-D-glucosamine (NAG), while sulfuric acid was most effective for glucosamine (GlcN) production. Palladium-carbon was the most efficient metal catalyst for NAG yield, while nickel powder catalyzed the highest GlcN production. It was observed that increasing chitin quantity, while keeping phosphoric acid constant, led to a decrease in NAG and GlcN yields. Temperature variations within the range of 100-120°C showed minimal impact on the hydrolysis results. Additionally, among three salt catalysts, ammonium formate and ammonium acetate were most effective for NAG and GlcN yields, respectively. These methods offer potential for preparing chitin monomers or their derivatives while reducing energy consumption and simplifying hydrolysis conditions.