The optimization of deacetylation process parameters for producing chitosan from isolated chitin shrimp shell waste was investigated using response surface methodology with central composite design (RSM-CCD). Three independent variables viz, NaOH concentration (X1), radiation power (X2), and reaction time (X3) were examined to determine their respective effects on the degree of deacetylation (DD). The DD of chitosan was also calculated using the baseline approach of the Fourier Transform Infrared (FTIR) spectra of the yields. RSM-CCD analysis showed that the optimal chitosan DD value of 96.45 % was obtained at an optimized condition of 63.41 % (w/v) NaOH concentration, 227.28 W radiation power, and 3.34 min deacetylation reaction. The DD was strongly controlled by NaOH concentration, irradiation power, and reaction duration. The coefficients of correlation were 0.257, 0.680, and 0.390, respectively. Because the procedure used microwave radiation absorption, radiation power had a substantial correlation of 0.600~0.800 compared to the two low variables, which were 0.200~0.400. This independently predicted robust quadratic model interaction has been validated for predicting the DD of chitin.

1. Introduction
2. Experimental Procedure
    2.1. Materials
    2.2. Chitin isolation from shrimp shells waste
    2.3. Experimental design for optimizing chitin deacetylation with response surface methodology
    2.4. Degree of deacetylation (DD) determinationusing FTIR
3. Result and Discussion
    3.1. Yield, appearance, and chemical characteristics of isolated chitin from shrimp shell waste
    3.2. Optimization of chitosan’s degree of deacetylation using the response surface method
4. Conclusion
Acknowledgement
References
Author Information

• Iqmal Tahir(Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia)
• Karna Wijaya(Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia) Corresponding author
• Mudasir(Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia)
• Dita Krismayanti(Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia)
• Aldino Javier Saviola(Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Gadjah Mada, Yogyakarta 55281, Indonesia)
• Roswanira Abdul Wahab(Department of Chemistry, Universiti Teknologi Malaysia, Johor 81310, Malaysia)
• Amalia Kurnia Amin(Research Center for Chemistry, National Research and Innovation Agency (BRIN), Tangerang Selatan 15314, Indonesia)
• Wahyu Dita Saputri(Research Center for Quantum Physics, National Research and Innovation Agency (BRIN), Tangerang Selatan 15314, Indonesia)
• Remi Ayu Pratika(Study Program of Chemistry, Faculty of Mathematics and Natural Science, Universitas Palangka Raya, Palangka Raya 73111, Indonesia)