High yield production of chitin nanocrystals via hydrochloric acid vapor pre-treatment

Abstract

Traditionally, chitin nanocrystals (ChNCs) are extracted from natural chitin suffered from huge chemical consumption and low yields. Herein, we show that ChNCs can be prepared in yields up to 95.5% by a pretreatment process using HCl vapor to assist exfoliation. It is shown that HCl vapor mainly caused disintegration of amorphous chitin, without excessive hydrolysis of the crystalline region. TEM images showed that chitin exposed to HCl vapor for a certain time readily separated into discernable rods with diameters in the nanoscale range. XRD and TGA analysis showed that the crystallinity and thermal stability of ChNCs were comparable to those of the untreated chitin. In addition, ChNCs was applied as efficient stabilizer for oil-in-water (O/W) emulsions.