In this paper, we explore the self-cleaning and washing durability of green-prepared ZnO NPs combined with cotton fabrics. Honeysuckle extract was used to prepare ZnO NPs with an average particle size of 15.3 nm. Cotton fabrics were then treated with oxalic acid (OA), tartaric acid (TA), and succinic acid (SA) as cross-linking agents, sodium hypophosphite as a catalyst, and after that, the ZnO NPs were applied to the cross-linked cotton fabrics by the padding to prepare the self-cleaning cotton fabrics. The morphology and structure of the fabric samples were characterized using FTIR, scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDS), and XRD. The optical properties of the cotton fabric samples were discussed by UV-vis diffuse reflectance spectrum, and the self-cleaning performance, wrinkle recovery angle and ultraviolet protection performance of the cotton fabric samples were analyzed. The results showed that the carboxyl groups of TA, OA, and SA were esterified with hydroxyl groups of the cotton fiber and formed a film on the surface of the cotton fabrics. ZnO NPs were successfully loaded onto the cotton fabrics by strong electrostatic interaction, causing the improvement of the washing resistance of the cross-linked fabrics. In addition, compared with uncross-linked fabrics, the wrinkle recovery performance of the cross-linked fabrics had also been greatly improved, and the UV protection factor reached 50+, thus obtaining an excellent self-cleaning, multifunctional cotton-based textile with anti-wrinkle and anti-ultraviolet properties.

5-Hydroxymethylfurfural (5-HMF) is one of the top valuable platform chemicals that can be derived from biomass. Herein, a facile, mild, and efficient catalytic conversion method was developed to convert chitin biomass into 5-HMF in lithium bromide molten salt hydrates (LiBr MSHs) with boric acid (BA) as the catalyst. About 49.6% 5-HMF yield was obtained from glucosamine (GlcN) in 65 wt % LiBr MSHs at 130 °C for 2 h with 800% BA addition. The system is applicable to other sugars, and the C2substituted group of sugars played a significant role in the 5-HMF yield. The 5-HMF yields were 81.3, 40.3, and 3.9% from fructose, glucose, and N-acetyl glucosamine (GlcNAc), respectively, under identical conditions. Combined with acid addition and Box−Behnken experiment designs, the direct conversion of chitosan and chitin were achieved at 140 °C for 5 h to produce 5-HMF with 21.6 and 15.3% yield. Ammonia quantitative analysis and NMR tests have been conducted, based on which a plausible reaction pathway was proposed. The LiBr MSHs and the BA catalyst facilitated the hydrolysis, deacetylation, and ringopening of chitin biomass. Especially, the catalyst BA played a key role in the formation of 5-HMF, as it was found to promote dehydration at the last step. The study put forward new avenues for chitin refinery to produce high-value furanic platform chemicals in cheap and green solvent systems.

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