The “shell biorefinery” has been proposed and developed rapidly in recent years, which valorizes the underestimated chitin biopolymer from oceanic waste to complement the lignocellulosic biomass for renewable chemicals. Herein, we exploited a simple and effective method to convert chitin biomass into acetic acid (AA) by using vanadium pentoxide (V₂O₅) and oxygen gas (O₂) in base-free water, which makes the process more environmentally and economically favorable than previous methods. Under optimal conditions, the highest AA yield was obtained in 33.4% and 30.0% from the chitin monomer N-acetyl-d-glucosamine (NAG) and ball milled chitin (BM chitin) polymer. The V₂O₅ catalyst has multifunctionally facilitated the hydrolysis, deacetylation, and subsequent oxidation into AA. FTIR and XRD analyses were conducted for the solid residues after the reaction. The FTIR spectra of the solid residues highly resembled that of chitin, inferring that chitin hydrolysis into NAG probably happened prior to deacetylation. Besides, XRD data demonstrated that the reaction system could effectively destruct the crystalline regions during the reaction. The study demonstrated a new catalytic approach for chitin biorefinery to renovate the shell waste into valuable chemicals.

中文翻译：

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低氧压力下无碱，钒催化的几丁质向乙酸的转化

近年来，已经提出并发展了“壳生物精炼厂”，它利用海洋废弃物中被低估的几丁质生物聚合物来补充可再生化学品的木质纤维素生物质。本文中，我们开发了一种简单有效的方法，通过在无碱水中使用五氧化二钒（V ₂ O ₅）和氧气（O ₂）将几丁质生物质转化为乙酸（AA），从而使该过程更加环保和经济比以前的方法更有利。在最佳条件下，在33.4％和30.0％来自甲壳质单体获得的最高产率AA Ñ乙酰基d -葡糖胺酶（NAG）和球磨壳多糖（几丁质BM）聚合物。V ₂ O ₅催化剂具有多功能促进水解，脱乙酰和随后氧化成AA的作用。反应后，对固体残留物进行了FTIR和XRD分析。固体残留物的FTIR光谱与甲壳质的光谱非常相似，这表明甲壳质水解成NAG可能发生在脱乙酰基作用之前。此外，XRD数据表明反应体系可以有效地破坏反应过程中的结晶区域。该研究证明了几丁质生物精炼厂的一种新催化方法，可将壳废料翻新为有价值的化学物质。