Gradient heating activated ammonium persulfate oxidation for efficient preparation of high-quality chitin nanofibers
APS is a cheap and eco-friendly oxidant which enables one-step extraction of nanochitin (NCh) from fishery wastes. However, it is challenging to improve the preparation efficiency and NCh quality simultaneously, owing to the uneven or uncontrollable oxidation . Herein, we propose a simple and controllable way to isolate chitin nanofibers (ChNFs) from squid pen by gradient heating activated (GHA)- ammonium persulfate (APS) oxidation. Compared to the isothermal activated (ITA)-APS oxidation, our strategy reduced the mass ratio of squid pen to APS from 1:45 to 1:6 and reaction time from 15 h to 8 h. Meanwhile, the as-prepared ChNFs exhibited high yield (91.5 %), light transmittance (98 % at 500 nm), crystallinity index (96.9 %), and carboxyl content (1.53 mmol/g). GHA-APS oxidation involved multiple continuous heating and isothermal stages. The former stimulates a moderate activation of APS and enhances the oxidation rate, while the latter provides a duration for surface chemistry. This non-isothermal heating facilitates the continuous decomposition of APS at a relatively high and consistent rate, thereby enhances its oxidation efficiency. Furthermore, green assessments indicate this method is simple, time-saving, eco-friendly and cost-effective. Overall, this work introduces a novel perspective for the industrial extraction of high-efficiency and high-quality nanomaterials .
危险品化学品经营许可证（带存储）