The impact of the different types of acid solution on the extraction and adsorption performance of chitin from shrimp shell waste

The properties of chitin-based adsorbents varied among studies since they are influenced by different factors, such as the types of base and acid used to extract the chitin. Therefore, this works aimed to investigate the impact of four different acid solutions on the extraction and properties of chitin from shrimp shell waste, and to evaluate the adsorption performance of the obtained chitin on removing dye from an aqueous solution. The result showed that H₂SO₄, HCl, and HNO₃ could remove high minerals from the shrimp shell, while the effect of CH₃COOH was inferior. The Fourier Transform Infrared (FTIR) and X-ray diffraction (XRD) indicated that the extracted chitin was α-amorphous structure, regardless of the type of acid solution. However, the type of acid solution influenced the crystallinity index of the extracted chitin. The Scanning Electron Microscope (SEM) showed both fibrillar material and porous structures. In addition, the chitin extracted through demineralization using H₂SO₄ was more effective in removing RBBR dye from aqueous solution, followed by HCl, HNO₃, and the last, CH₃COOH treatment. The performances of chitin-based adsorbent could be attributed to the strength of acid solution used to remove mineral during the extraction process and the obtained pore structures.