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An environmentally friendly approach for the comprehensive utilization of shrimp shell waste was reported. Instant catapult steam explosion (ICSE) was employed for shrimp shell waste pretreatment. After ICSE, lower crystallinity and greater surface areas of shrimp shells were achieved, which significantly enhanced the extraction of chitin. Compared to the traditional method, weaker organic acid (HCOOH) and much lower dosages of KOH (90% molar less) were used, and chitin with a high demineralization rate (98.2%) and deproteinization rate (97.7%) was obtained. The wastewater was neutralized by simply intermixing, and it was recycled as a potential plant fertilizer because it contained more oligopeptides, calcium, and potassium, but it was less salty and therefore non-toxic to plants. The whole process produced less solid waste and no waste water. The obtained chitin also showed a low degree of acetylation (50.5%), which demonstrates the potential for environmentally friendly preparation of chitosan in dilute alkali through ICSE.

Deep eutectic solvents (DESs) were proposed for the extraction of polysaccharides from Poria cocos (PCPs). Six types of DESs were prepared, and the DES composed of choline chloride and oxalic acid was proved to be suitable. Based on the results of single-factor test, the Box-Behnken experimental design with response surface methodology was carried out, giving the optimal extraction conditions including mole ratio of 1:2 (choline chloride:oxalic acid) and extraction 15 minutes at 100°C. Under the optimal extraction conditions, the extraction yield (46.24% ± 0.13%) was 8.6 times higher than that of hot water. The reusability of DES was demonstrated by a 6-run test, and an extraction yield of PCP was 38.40% ± 0.23% after reusing for 6 times without adding any additional chemicals. Moreover, molecular weight distributions of the resulting PCP were analyzed, and then mainly distributed in the range of 753 to 3578 g/mol. Therefore, DESs were proved to be an excellent extraction solvent alternative to the extraction of PCP.

A template-assisted wet etching method for the preparation of perovskite micro-structure array is proposed. This method has a superiority of flexible graph design, controllable size and high precision.

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