Preparation characteristics and accelerating denitrification effectiveness of polyamide 6 modified by AQS

Abstract

In this study, the functional polymer biocarrier polyamide 6 (PA6) modified by anthraquinone-2-sulphonate (AQS) was synthesized by hydrolysis and sulphonation reactions. The optimal hydrolysis conditions of PA6 were 35 C, 3 mol/L HCl and 72 h reaction time. The optimal sulphonation conditions of PA6 modified by AQS (PA6-AQS) were 30 C and 6 h reaction time. The morphology and heat resistance of PA6-AQS were analysed by scanning electron microscopy, thermogravimetric analysis and differential scanning calorimetry. The AQS content of PA6-AQS, determined by an elemental analysis, was approximately 0.11 mmol/g. The denitrification efficiency was enhanced by 1.78-fold with PA6-AQS. Repeated-batch operations showed that the denitrification efficiency with PA6-AQS became stabilized above 80% of the original value and exhibited a better catalytic activity and durability.